QObject Class Reference

The QObject class is the base class of all Qt objects. More...

#include <qobject.h>

Inheritance diagram for QObject:

Public Slots
void	deleteLater ()
	Schedules this object for deletion. More...

Signals
void	destroyed (QObject *=0)
	This signal is emitted immediately before the object obj is destroyed, and can not be blocked. More...

Public Functions
bool	blockSignals (bool b)
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it). More...
const QObjectList &	children () const
	Returns a list of child objects. More...
bool	connect (const QObject *sender, const char *signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const
bool	disconnect (const char *signal=0, const QObject *receiver=0, const char *member=0)
bool	disconnect (const QObject *receiver, const char *member=0)
void	dumpObjectInfo ()
	Dumps information about signal connections, etc. More...
void	dumpObjectTree ()
	Dumps a tree of children to the debug output. More...
QList< QByteArray >	dynamicPropertyNames () const
	Returns the names of all properties that were dynamically added to the object using setProperty(). More...
virtual bool	event (QEvent *)
	This virtual function receives events to an object and should return true if the event e was recognized and processed. More...
virtual bool	eventFilter (QObject *, QEvent *)
	Filters events if this object has been installed as an event filter for the watched object. More...
template<typename T >
T	findChild (const QString &aName=QString()) const
	Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object. More...
template<typename T >
QList< T >	findChildren (const QString &aName=QString()) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects. More...
template<typename T >
QList< T >	findChildren (const QRegExp &re) const
bool	inherits (const char *classname) const
	Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false. More...
void	installEventFilter (QObject *)
	Installs an event filter filterObj on this object. More...
bool	isWidgetType () const
	Returns true if the object is a widget; otherwise returns false. More...
void	killTimer (int id)
	Kills the timer with timer identifier, id. More...
virtual const QMetaObject *	metaObject () const
	Returns a pointer to the meta-object of this object. More...
void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children. More...
QString	objectName () const
QObject *	parent () const
	Returns a pointer to the parent object. More...
QVariant	property (const char *name) const
	Returns the value of the object's name property. More...
Q_INVOKABLE	QObject (QObject *parent=0)
	Constructs an object with parent object parent. More...
void	removeEventFilter (QObject *)
	Removes an event filter object obj from this object. More...
void	setObjectName (const QString &name)
void	setParent (QObject *)
	Makes the object a child of parent. More...
bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value. More...
void	setUserData (uint id, QObjectUserData *data)
bool	signalsBlocked () const
	Returns true if signals are blocked; otherwise returns false. More...
int	startTimer (int interval)
	Starts a timer and returns a timer identifier, or returns zero if it could not start a timer. More...
QThread *	thread () const
	Returns the thread in which the object lives. More...
QObjectUserData *	userData (uint id) const
virtual	~QObject ()
	Destroys the object, deleting all its child objects. More...

Static Public Functions
static bool	connect (const QObject *sender, const char *signal, const QObject *receiver, const char *member, Qt::ConnectionType=Qt::AutoConnection)
	Creates a connection of the given type from the signal in the sender object to the method in the receiver object. More...
static bool	connect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)
static bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *member)
	Disconnects signal in object sender from method in object receiver. More...
static bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &member)
static uint	registerUserData ()
static QString	tr (const char *sourceText, const char *comment=0, int n=-1)
static QString	trUtf8 (const char *sourceText, const char *comment=0, int n=-1)

Static Public Variables
static const QMetaObject	staticMetaObject
	This variable stores the meta-object for the class. More...

Protected Functions
virtual void	childEvent (QChildEvent *)
	This event handler can be reimplemented in a subclass to receive child events. More...
virtual void	connectNotify (const char *signal)
	This virtual function is called when something has been connected to signal in this object. More...
virtual void	customEvent (QEvent *)
	This event handler can be reimplemented in a subclass to receive custom events. More...
virtual void	disconnectNotify (const char *signal)
	This virtual function is called when something has been disconnected from signal in this object. More...
	QObject (QObjectPrivate &dd, QObject *parent=0)
int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal. More...
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns 0. More...
int	senderSignalIndex () const
virtual void	timerEvent (QTimerEvent *)
	This event handler can be reimplemented in a subclass to receive timer events for the object. More...

Protected Variables
QScopedPointer< QObjectData >	d_ptr

Static Protected Variables
static const QMetaObject	staticQtMetaObject

Properties
QString	objectName
	the name of this object More...

Friends
class	QApplication
class	QApplicationPrivate
class	QCoreApplication
class	QCoreApplicationPrivate
struct	QMetaObject
class	QThreadData
class	QWidget

Related Functions
(Note that these are not member functions.)
T	qFindChildqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()
QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QRegExp &regExp)()
T *	qobject_cast (QObject *object)
	QObjectList
void *	qt_find_obj_child (QObject *parent, const char *type, const QString &name)
	Returns a pointer to the object named name that inherits type and with a given parent. More...

Detailed Description

The QObject class is the base class of all Qt objects.

Note

This class or function is reentrant.

QObject is the heart of the Qt Object Model. The central feature in this model is a very powerful mechanism for seamless object communication called signals and slots. You can connect a signal to a slot with connect() and destroy the connection with disconnect(). To avoid never ending notification loops you can temporarily block signals with blockSignals(). The protected functions connectNotify() and disconnectNotify() make it possible to track connections.

QObjects organize themselves in Object Trees & Ownership {object trees}. When you create a QObject with another object as parent, the object will automatically add itself to the parent's children() list. The parent takes ownership of the object; i.e., it will automatically delete its children in its destructor. You can look for an object by name and optionally type using findChild() or findChildren().

Every object has an objectName() and its class name can be found via the corresponding metaObject() (see QMetaObject::className()). You can determine whether the object's class inherits another class in the QObject inheritance hierarchy by using the inherits() function.

When an object is deleted, it emits a destroyed() signal. You can catch this signal to avoid dangling references to QObjects.

QObjects can receive events through event() and filter the events of other objects. See installEventFilter() and eventFilter() for details. A convenience handler, childEvent(), can be reimplemented to catch child events.

Last but not least, QObject provides the basic timer support in Qt; see QTimer for high-level support for timers.

Notice that the Q_OBJECT macro is mandatory for any object that implements signals, slots or properties. You also need to run the Meta Object Compiler on the source file. We strongly recommend the use of this macro in all subclasses of QObject regardless of whether or not they actually use signals, slots and properties, since failure to do so may lead certain functions to exhibit strange behavior.

All Qt widgets inherit QObject. The convenience function isWidgetType() returns whether an object is actually a widget. It is much faster than qobject_cast<QWidget *>(obj) or obj->inherits("QWidget").

Some QObject functions, e.g. children(), return a QObjectList. QObjectList is a typedef for QList<QObject *>.

Thread Affinity

A QObject instance is said to have a thread affinity, or that it lives in a certain thread. When a QObject receives a queued signal or a The Event System::Sending Events{posted event}, the slot or event handler will run in the thread that the object lives in.

Note

If a QObject has no thread affinity (that is, if thread() returns zero), or if it lives in a thread that has no running event loop, then it cannot receive queued signals or posted events.

By default, a QObject lives in the thread in which it is created. An object's thread affinity can be queried using thread() and changed using moveToThread().

All QObjects must live in the same thread as their parent. Consequently:

setParent() will fail if the two QObjects involved live in different threads.

• When a QObject is moved to another thread, all its children will be automatically moved too.
• moveToThread() will fail if the QObject has a parent.
• If QObject are created within QThread::run(), they cannot become children of the QThread object because the QThread does not live in the thread that calls QThread::run().

Note

A QObject's member variables do not automatically become its children. The parent-child relationship must be set by either passing a pointer to the child's constructor, or by calling setParent(). Without this step, the object's member variables will remain in the old thread when moveToThread() is called.

No copy constructor or assignment operator

QObject has neither a copy constructor nor an assignment operator. This is by design. Actually, they are declared, but in a private section with the macro Q_DISABLE_COPY(). In fact, all Qt classes derived from QObject (direct or indirect) use this macro to declare their copy constructor and assignment operator to be private. The reasoning is found in the discussion on Identity vs Value {Identity vs Value} on the Qt Object Model page.

The main consequence is that you should use pointers to QObject (or to your QObject subclass) where you might otherwise be tempted to use your QObject subclass as a value. For example, without a copy constructor, you can't use a subclass of QObject as the value to be stored in one of the container classes. You must store pointers.

Auto-Connection

Qt's meta-object system provides a mechanism to automatically connect signals and slots between QObject subclasses and their children. As long as objects are defined with suitable object names, and slots follow a simple naming convention, this connection can be performed at run-time by the QMetaObject::connectSlotsByName() function.

uic generates code that invokes this function to enable auto-connection to be performed between widgets on forms created with . More information about using auto-connection with is given in the Using a Designer UI File in Your Application section of the manual.

Dynamic Properties

From Qt 4.2, dynamic properties can be added to and removed from QObject instances at run-time. Dynamic properties do not need to be declared at compile-time, yet they provide the same advantages as static properties and are manipulated using the same API - using property() to read them and setProperty() to write them.

From Qt 4.3, dynamic properties are supported by Qt Designer's Widget Editing Mode::The Property Editor{Qt Designer}, and both standard Qt widgets and user-created forms can be given dynamic properties.

(i18n)

Internationalization (i18n)

All QObject subclasses support Qt's translation features, making it possible to translate an application's user interface into different languages.

To make user-visible text translatable, it must be wrapped in calls to the tr() function. This is explained in detail in the Writing Source Code for Translation document.

See also

QMetaObject, QPointer, QObjectCleanupHandler, Q_DISABLE_COPY()

{Object Trees & Ownership}

Definition at line 111 of file qobject.h.

Constructors and Destructors

QObject() [1/2]

QObject::QObject ( QObject *  parent = 0 )

explicit

Constructs an object with parent object parent.

The parent of an object may be viewed as the object's owner. For instance, a dialog box is the parent of the OK and Cancel buttons it contains.

The destructor of a parent object destroys all child objects.

Setting parent to 0 constructs an object with no parent. If the object is a widget, it will become a top-level window.

See also

parent(), findChild(), findChildren()

Definition at line 753 of file qobject.cpp.

Referenced by connManager(), QThread::priority(), QCopChannel::QCopChannel(), QCoreApplication::QCoreApplication(), QDeclarativePixmapReader::QDeclarativePixmapReader(), QDeclarativeXmlQueryEngine::QDeclarativeXmlQueryEngine(), QFtp::QFtp(), QHttpNetworkConnection::QHttpNetworkConnection(), QSignalMapper::QSignalMapper(), QSocketNotifier::QSocketNotifier(), QSound::QSound(), QTimer::QTimer(), QTranslator::QTranslator(), QValidator::QValidator(), QWidget::QWidget(), QWSServer::QWSServer(), and QAction::setFont().

    : d_ptr(new QObjectPrivate)
{
    Q_D(QObject);
    d_ptr->q_ptr = this;
    d->threadData = (parent && !parent->thread()) ? parent->d_func()->threadData : QThreadData::current();
    d->threadData->ref();
    if (parent) {
        QT_TRY {
            if (!check_parent_thread(parent, parent ? parent->d_func()->threadData : 0, d->threadData))
                parent = 0;
            setParent(parent);
        } QT_CATCH(...) {
            d->threadData->deref();
            QT_RETHROW;
        }
    }
    qt_addObject(this);
}

~QObject()

QObject::~QObject ( )

virtual

Destroys the object, deleting all its child objects.

All signals to and from the object are automatically disconnected, and any pending posted events for the object are removed from the event queue. However, it is often safer to use deleteLater() rather than deleting a QObject subclass directly.

Warning

All child objects are deleted. If any of these objects are on the stack or global, sooner or later your program will crash. We do not recommend holding pointers to child objects from outside the parent. If you still do, the destroyed() signal gives you an opportunity to detect when an object is destroyed.

Deleting a QObject while pending events are waiting to be delivered can cause a crash. You must not delete the QObject directly if it exists in a different thread than the one currently executing. Use deleteLater() instead, which will cause the event loop to delete the object after all pending events have been delivered to it.

See also

deleteLater()

Definition at line 853 of file qobject.cpp.

{
    Q_D(QObject);
    d->wasDeleted = true;
    d->blockSig = 0; // unblock signals so we always emit destroyed()

    if (d->hasGuards && !d->isWidget) {
        // set all QPointers for this object to zero - note that
        // ~QWidget() does this for us, so we don't have to do it twice
        QObjectPrivate::clearGuards(this);
    }

    if (d->sharedRefcount) {
        if (d->sharedRefcount->strongref > 0) {
            qWarning("QObject: shared QObject was deleted directly. The program is malformed and may crash.");
            // but continue deleting, it's too late to stop anyway
        }

        // indicate to all QWeakPointers that this QObject has now been deleted
        d->sharedRefcount->strongref = 0;
        if (!d->sharedRefcount->weakref.deref())
            delete d->sharedRefcount;
    }


    if (d->isSignalConnected(0)) {
        QT_TRY {
            emit destroyed(this);
        } QT_CATCH(...) {
            // all the signal/slots connections are still in place - if we don't
            // quit now, we will crash pretty soon.
            qWarning("Detected an unexpected exception in ~QObject while emitting destroyed().");
            QT_RETHROW;
        }
    }

    if (d->declarativeData)
        QAbstractDeclarativeData::destroyed(d->declarativeData, this);

    // set ref to zero to indicate that this object has been deleted
    if (d->currentSender != 0)
        d->currentSender->ref = 0;
    d->currentSender = 0;

    if (d->connectionLists || d->senders) {
        QMutex *signalSlotMutex = signalSlotLock(this);
        QMutexLocker locker(signalSlotMutex);

        // disconnect all receivers
        if (d->connectionLists) {
            ++d->connectionLists->inUse;
            int connectionListsCount = d->connectionLists->count();
            for (int signal = -1; signal < connectionListsCount; ++signal) {
                QObjectPrivate::ConnectionList &connectionList =
                    (*d->connectionLists)[signal];

                while (QObjectPrivate::Connection *c = connectionList.first) {
                    if (!c->receiver) {
                        connectionList.first = c->nextConnectionList;
                        delete c;
                        continue;
                    }

                    QMutex *m = signalSlotLock(c->receiver);
                    bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m);

                    if (c->receiver) {
                        *c->prev = c->next;
                        if (c->next) c->next->prev = c->prev;
                    }
                    if (needToUnlock)
                        m->unlockInline();

                    connectionList.first = c->nextConnectionList;
                    delete c;
                }
            }

            if (!--d->connectionLists->inUse) {
                delete d->connectionLists;
            } else {
                d->connectionLists->orphaned = true;
            }
            d->connectionLists = 0;
        }

        // disconnect all senders
        QObjectPrivate::Connection *node = d->senders;
        while (node) {
            QObject *sender = node->sender;
            QMutex *m = signalSlotLock(sender);
            node->prev = &node;
            bool needToUnlock = QOrderedMutexLocker::relock(signalSlotMutex, m);
            //the node has maybe been removed while the mutex was unlocked in relock?
            if (!node || node->sender != sender) {
                m->unlockInline();
                continue;
            }
            node->receiver = 0;
            QObjectConnectionListVector *senderLists = sender->d_func()->connectionLists;
            if (senderLists)
                senderLists->dirty = true;

            node = node->next;
            if (needToUnlock)
                m->unlockInline();
        }
    }

    if (!d->children.isEmpty())
        d->deleteChildren();

    qt_removeObject(this);

    if (d->parent)        // remove it from parent object
        d->setParent_helper(0);

#ifdef QT_JAMBI_BUILD
    if (d->inEventHandler) {
        qWarning("QObject: Do not delete object, '%s', during its event handler!",
                 objectName().isNull() ? "unnamed" : qPrintable(objectName()));
    }
#endif
}

QObject() [2/2]

QObject::QObject ( QObjectPrivate &  dd, QObject *  parent = 0  )

protected

Warning

This function is not part of the public interface.

Definition at line 801 of file qobject.cpp.

    : d_ptr(&dd)
{
    Q_D(QObject);
    d_ptr->q_ptr = this;
    d->threadData = (parent && !parent->thread()) ? parent->d_func()->threadData : QThreadData::current();
    d->threadData->ref();
    if (parent) {
        QT_TRY {
            if (!check_parent_thread(parent, parent ? parent->d_func()->threadData : 0, d->threadData))
                parent = 0;
            if (d->isWidget) {
                if (parent) {
                    d->parent = parent;
                    d->parent->d_func()->children.append(this);
                }
                // no events sent here, this is done at the end of the QWidget constructor
            } else {
                setParent(parent);
            }
        } QT_CATCH(...) {
            d->threadData->deref();
            QT_RETHROW;
        }
    }
    qt_addObject(this);
}

Functions

blockSignals()

bool QObject::blockSignals

(

bool

block

)

If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it).

If block is false, no such blocking will occur.

The return value is the previous value of signalsBlocked().

Note that the destroyed() signal will be emitted even if the signals for this object have been blocked.

See also

signalsBlocked()

Definition at line 1406 of file qobject.cpp.

Referenced by QPlainTextEditPrivate::_q_adjustScrollbars(), QAbstractSpinBoxPrivate::_q_editorCursorPositionChanged(), QHttpPrivate::_q_slotError(), QHttpPrivate::_q_slotReadyRead(), QHttpPrivate::_q_slotSendRequest(), QTabWidgetPrivate::_q_tabMoved(), QFontComboBoxPrivate::_q_updateModel(), QWorkspace::cascade(), QDateTimeEditPrivate::clearSection(), QMenuPrivate::hideMenu(), isProcessBeingDebugged(), operator>>(), QDataStream::QDataStream(), QSocks5SocketEnginePrivate::reauthenticate(), QTreeModel::removeRows(), QItemSelectionModel::reset(), QColSpinBox::setValue(), QDateTimeEditPrivate::syncCalendarWidget(), QWorkspace::tile(), QMdiAreaPrivate::updateActiveWindow(), QDateTimeEditPrivate::updateEdit(), QAbstractSpinBoxPrivate::updateEdit(), QDockAreaLayoutInfo::updateTabBar(), and QTextStreamPrivate::~QTextStreamPrivate().

{
    Q_D(QObject);
    bool previous = d->blockSig;
    d->blockSig = block;
    return previous;
}

childEvent()

void QObject::childEvent ( QChildEvent *  )

protectedvirtual

This event handler can be reimplemented in a subclass to receive child events.

The event is passed in the event parameter.

QEvent::ChildAdded and QEvent::ChildRemoved events are sent to objects when children are added or removed. In both cases you can only rely on the child being a QObject, or if isWidgetType() returns true, a QWidget. (This is because, in the ChildAdded case, the child is not yet fully constructed, and in the ChildRemoved case it might have been destructed already).

QEvent::ChildPolished events are sent to widgets when children are polished, or when polished children are added. If you receive a child polished event, the child's construction is usually completed. However, this is not guaranteed, and multiple polish events may be delivered during the execution of a widget's constructor.

For every child widget, you receive one ChildAdded event, zero or more ChildPolished events, and one ChildRemoved event.

The ChildPolished event is omitted if a child is removed immediately after it is added. If a child is polished several times during construction and destruction, you may receive several child polished events for the same child, each time with a different virtual table.

See also

event()

Reimplemented in QWorkspaceChild, QLayout, QMdiArea, QToolBar, QMdiSubWindow, QSplitter, QWorkspace, and QGroupBox.

Definition at line 1332 of file qobject.cpp.

Referenced by QToolBar::childEvent(), QAnimationGroup::event(), event(), and QToolBar::isAreaAllowed().

{
}

children()

const QObjectList & QObject::children ( ) const

inline

Returns a list of child objects.

The QObjectList class is defined in the <QObject> header file as the following:

src/corelib/kernel/qobject.h /typedef .*QObjectList/ QObjectList

The first child added is the first object in the list and the last child added is the last object in the list, i.e. new children are appended at the end.

Note that the list order changes when QWidget children are raised or lowered. A widget that is raised becomes the last object in the list, and a widget that is lowered becomes the first object in the list.

See also

findChild(), findChildren(), parent(), setParent()

Definition at line 197 of file qobject.h.

Referenced by QWidgetPrivate::activateChildLayoutsRecursively(), boundingRectOfFloatsInSelection(), buddyString(), QDeclarativeEngineDebugService::buildObjectDump(), QDeclarativeEngineDebugService::buildStatesList(), QDeclarativeContents::calcHeight(), QDeclarativeContents::calcWidth(), QDeclarativeItem::childAt(), QWidgetPrivate::childAt_helper(), QWidgetPrivate::childAtRecursiveHelper(), QGraphicsItemPrivate::children_at(), children_at_helper(), QGraphicsItemPrivate::childrenList(), QStatePrivate::childStates(), childWidgets(), QDeclarativeContents::complete(), QWidgetPrivate::createRecursively(), QDeclarativeFlickablePrivate::data_at(), QDeclarativeFlickablePrivate::data_clear(), QDeclarativeFlickablePrivate::data_count(), QTreeView::drawBranches(), QWidgetPrivate::drawWidget(), QWidget::ensurePolished(), QDockWidget::event(), find_child(), findChildObject(), findChildrenHelper(), findMenuBar(), QWidgetPrivate::getOpaqueChildren(), QWidgetPrivate::hideChildren(), QStatePrivate::historyStates(), QTreeModel::insertColumns(), QAxServerBase::internalCreate(), QMdiAreaPrivate::internalRaise(), killTimer(), QTreeViewPrivate::layout(), QWidget::lower(), make_win_eventUPP(), markFrames(), QDirModel::parent(), QDBusAdaptorConnector::polish(), QDeclarativeEngineDebugService::prepareDeferredObjects(), QDeclarativeBasePositioner::prePositioning(), QWidgetPrivate::propagatePaletteChange(), q_createNativeChildrenAndSetParent(), qDBusFindAdaptorConnector(), QObject(), QScript::qobjectProtoFuncFindChildren(), qt_find_obj_child(), qt_qFindChild_helper(), qt_qFindChildren_helper(), qt_set_windows_updateScrollBar(), qt_x11_recreateNativeWidgetsRecursive(), QWidget::raise(), QAccessibleGroupBox::relationTo(), QFileSystemModel::remove(), QStyleSheetStyle::repolish(), QDeclarativeItemPrivate::resources_at(), QDeclarativeItemPrivate::resources_clear(), QDeclarativeItemPrivate::resources_count(), QDeclarativeParentChange::saveCurrentValues(), QWidget::scroll(), QWidgetPrivate::sendPendingMoveAndResizeEvents(), sendResizeEvents(), QWidgetPrivate::setEnabled_helper(), QDeclarativeItemPrivate::setImplicitLayoutMirror(), QWidgetPrivate::setLayoutDirection_helper(), QWidgetPrivate::setLocale_helper(), QWidgetResizeHandler::setMouseCursor(), setObjectName(), QObjectPrivate::setParent_helper(), QDeclarativePropertyPrivate::setSignalExpression(), QLocalSocket::setSocketDescriptor(), QWidgetPrivate::setStyle_helper(), QWidgetPrivate::setUpdatesEnabled_helper(), QDeclarativeVisualItemModel::setWatchedRoles(), QWidgetPrivate::setWindowIcon_helper(), QWidgetPrivate::showChildren(), QDeclarativePropertyPrivate::signalExpression(), QWidget::stackUnder(), QStateMachinePrivate::stateEntryLessThan(), QStateMachinePrivate::stateExitLessThan(), QWidgetBackingStore::staticContents(), QWidgetPrivate::subtractOpaqueChildren(), QWidgetPrivate::subtractOpaqueSiblings(), QMdiAreaPrivate::subWindowList(), QStatePrivate::transitions(), QWidgetBackingStoreTracker::unregisterWidgetSubtree(), QWidgetPrivate::updateFont(), QWidgetBackingStore::updateLists(), QWorkspace::windowList(), QDeclarativeContents::~QDeclarativeContents(), and QSingleDesktopWidget::~QSingleDesktopWidget().

{ return d_ptr->children; }

connect() [1/3]

bool QObject::connect ( const QObject *  sender, const char *  signal, const QObject *  receiver, const char *  method, Qt::ConnectionType  type = Qt::AutoConnection  )

static

Creates a connection of the given type from the signal in the sender object to the method in the receiver object.

Note

This class or function is threadsafe.

Returns true if the connection succeeds; otherwise returns false.

You must use the SIGNAL() and SLOT() macros when specifying the signal and the method, for example:

QLabel *label = new QLabel;
QScrollBar *scrollBar = new QScrollBar;
QObject::connect(scrollBar, SIGNAL(valueChanged(int)),
                 label,  SLOT(setNum(int)));

This example ensures that the label always displays the current scroll bar value. Note that the signal and slots parameters must not contain any variable names, only the type. E.g. the following would not work and return false:

// WRONG
QObject::connect(scrollBar, SIGNAL(valueChanged(int value)),
                 label, SLOT(setNum(int value)));

A signal can also be connected to another signal:

class MyWidget : public QWidget
{
    Q_OBJECT

public:
    MyWidget();

signals:
    void buttonClicked();

private:
    QPushButton *myButton;
};

MyWidget::MyWidget()
{
    myButton = new QPushButton(this);
    connect(myButton, SIGNAL(clicked()),
            this, SIGNAL(buttonClicked()));
}

In this example, the MyWidget constructor relays a signal from a private member variable, and makes it available under a name that relates to MyWidget.

A signal can be connected to many slots and signals. Many signals can be connected to one slot.

If a signal is connected to several slots, the slots are activated in the same order as the order the connection was made, when the signal is emitted.

The function returns true if it successfully connects the signal to the slot. It will return false if it cannot create the connection, for example, if QObject is unable to verify the existence of either signal or method, or if their signatures aren't compatible.

By default, a signal is emitted for every connection you make; two signals are emitted for duplicate connections. You can break all of these connections with a single disconnect() call. If you pass the Qt::UniqueConnection type, the connection will only be made if it is not a duplicate. If there is already a duplicate (exact same signal to the exact same slot on the same objects), the connection will fail and connect will return false.

The optional type parameter describes the type of connection to establish. In particular, it determines whether a particular signal is delivered to a slot immediately or queued for delivery at a later time. If the signal is queued, the parameters must be of types that are known to Qt's meta-object system, because Qt needs to copy the arguments to store them in an event behind the scenes. If you try to use a queued connection and get the error message

QObject::connect: Cannot queue arguments of type 'MyType'
(Make sure 'MyType' is registered using qRegisterMetaType().)

call qRegisterMetaType() to register the data type before you establish the connection.

See also

disconnect(), sender(), qRegisterMetaType(), Q_DECLARE_METATYPE()

Definition at line 2580 of file qobject.cpp.

Referenced by QNetworkReplyImplPrivate::_q_bufferOutgoingData(), QAbstractSocketPrivate::_q_connectToNextAddress(), QTextControlPrivate::_q_documentLayoutChanged(), QGraphicsScenePrivate::_q_emitUpdated(), QWSServerPrivate::_q_newConnection(), QScriptDebuggerLocalsWidgetPrivate::_q_onCompletionTaskFinished(), QNetworkReplyImplPrivate::_q_startOperation(), QDeclarativeItemPrivate::_states(), QmlJSDebugger::AbstractViewInspector::AbstractViewInspector(), QToolButton::actionEvent(), QMenuBar::actionEvent(), QMenu::actionEvent(), QNetworkManagerInterface::activateConnection(), QObjectCleanupHandler::add(), _IapAddTimer::add(), QDBusPendingCallWatcherHelper::add(), QActionGroup::addAction(), QMenuBar::addAction(), QMenu::addAction(), QToolBar::addAction(), QDialogButtonBoxPrivate::addButton(), QDeclarativeAnchorsPrivate::addDepend(), QJSDebugService::addEngine(), QWizardPrivate::addField(), QPrintPropertiesDialog::addItemToOptions(), QAxScriptManager::addObject(), QWindowsFileSystemWatcherEngine::addPaths(), QConnmanEngine::addServiceConfiguration(), QGLShaderProgram::addShader(), QMainWindow::addToolBar(), QWorkspace::addWindow(), QApplication::alert(), QWidgetAnimator::animate(), QCopChannel::answer(), QMdiAreaPrivate::appendChild(), QStateMachinePrivate::applyProperties(), QDeclarativeXmlListModel::classBegin(), QScriptDebugger::clearConsoleAction(), QScriptDebugger::clearDebugOutputAction(), QScriptDebugger::clearErrorLogAction(), QScriptDebuggerLocalsWidgetPrivate::complete(), QDeclarativePath::componentComplete(), QBBVirtualKeyboardPps::connect(), QUnixSocket::connect(), QWizardPrivate::connectButton(), QDeclarativePixmap::connectDownloadProgress(), QDeclarativePixmap::connectFinished(), QOfonoManagerInterface::connectNotify(), QConnmanManagerInterface::connectNotify(), QOfonoModemInterface::connectNotify(), QOfonoNetworkRegistrationInterface::connectNotify(), QOfonoNetworkOperatorInterface::connectNotify(), QConnmanServiceInterface::connectNotify(), QOfonoSimInterface::connectNotify(), QConnmanTechnologyInterface::connectNotify(), QOfonoDataConnectionManagerInterface::connectNotify(), QOfonoPrimaryDataContextInterface::connectNotify(), QOfonoSmsInterface::connectNotify(), QDeclarativeProperty::connectNotifySignal(), ShaderEffectItem::connectPropertySignals(), QDBusConnectionPrivate::connectSignal(), QFtpDTP::connectToHost(), QProxyModel::connectToModel(), QAnimationGroupPrivate::connectUncontrolledAnimation(), connManager(), QScriptDebugger::continueAction(), QMdi::ControlContainer::ControlContainer(), QLineControl::copy(), QSoftKeyManager::createAction(), QmlJSDebugger::BoundingRectHighlighter::createBoundingBox(), QProcessPrivate::createChannel(), QColumnViewPrivate::createColumn(), QmlJSDebugger::LiveSelectionTool::createContextMenu(), QScriptEngineDebuggerPrivate::createDebugger(), QBBIntegration::createDisplay(), QScriptDebuggerLocalsItemDelegate::createEditor(), QScriptBreakpointsItemDelegate::createEditor(), QToolBarLayout::createItem(), QSoftKeyManager::createKeyedAction(), QFileDialogPrivate::createMenuActions(), QUndoGroup::createRedoAction(), QUndoStack::createRedoAction(), QNetworkAccessManager::createRequest(), QNetworkAccessManagerPrivate::createSession(), QLineEdit::createStandardContextMenu(), QFileDialogPrivate::createToolButtons(), QUndoGroup::createUndoAction(), QUndoStack::createUndoAction(), QFileDialogPrivate::createWidgets(), QWSDisplay::Data::Data(), QMenuBar::defaultAction(), QCopChannel::detach(), QNetworkManagerEngine::deviceAdded(), QAbstractSocket::disconnectFromHostImplementation(), QDeclarativeFontObject::download(), QVGPaintEngine::drawCachedGlyphs(), QAbstractItemViewPrivate::editor(), QNetworkAccessCache::emitEntryReady(), QInputDialogPrivate::ensureComboBox(), QIcdEngine::ensureDBusConnection(), QInputDialogPrivate::ensureDoubleSpinBox(), QInputDialogPrivate::ensureEnabledConnection(), QInputDialogPrivate::ensureIntSpinBox(), QInputDialogPrivate::ensureLayout(), QInputDialogPrivate::ensureLineEdit(), QInputDialogPrivate::ensureListView(), QLabelPrivate::ensureTextControl(), QDialog::exec(), QDeclarativeViewPrivate::execute(), QWSSoundServerPrivate::feedDevice(), QScriptDebugger::findInScriptAction(), QScriptDebugger::findNextInScriptAction(), QScriptDebugger::findPreviousInScriptAction(), QDeclarativeInclude::finished(), QLineEdit::focusInEvent(), QNetworkSessionManagerPrivate::forceSessionClose(), QNetworkAccessFtpBackend::ftpConnectionReady(), QMainWindowLayout::getTabBar(), QScriptDebugger::goToLineAction(), QWizardPrivate::handleAeroStyleChange(), QGLWindowSurface::hijackWindow(), QWorkspaceChild::iconWidget(), QGraphicsSvgItemPrivate::init(), QToolButtonPrivate::init(), QTextBrowserPrivate::init(), QColorDialogPrivate::init(), QTextEditPrivate::init(), QCompleterPrivate::init(), QToolBarPrivate::init(), QDialPrivate::init(), QDeclarativeTextEditPrivate::init(), QAbstractScrollAreaPrivate::init(), QFontDialogPrivate::init(), QDockWidgetPrivate::init(), QLineEditPrivate::init(), QProgressDialogPrivate::init(), QAuServerNAS::init(), QFileSystemWatcherPrivate::init(), QAbstractItemViewPrivate::init(), QPlainTextEditPrivate::init(), QSidebar::init(), QGraphicsSceneIndexPrivate::init(), QHttpPrivate::init(), QHttpNetworkConnectionChannel::init(), QStandardItemModelPrivate::init(), QTableViewPrivate::init(), QTabBarPrivate::init(), QPrintPreviewDialogPrivate::init(), QDeclarativeGridViewPrivate::init(), Maemo::IcdPrivate::init(), QMessageBoxPrivate::init(), QPrintPreviewWidgetPrivate::init(), QTabWidgetPrivate::init(), QDeclarativeListViewPrivate::init(), QPageSetupDialogPrivate::init(), QVNCServer::init(), QWorkspacePrivate::init(), QDateTimeEditPrivate::initCalendarPopup(), QFileSystemWatcherPrivate::initForcedEngine(), QSocks5SocketEngine::initialize(), QHttpSocketEngine::initialize(), QConnmanEngine::initialize(), QNetworkManagerEngine::initialize(), QTreeViewPrivate::initialize(), QColumnViewPrivate::initialize(), QSocks5SocketEnginePrivate::initialize(), QItemSelectionModelPrivate::initModel(), QFileSystemWatcherPrivate::initPollerEngine(), QWSServerPrivate::initServer(), QStyleSheetStyle::initWidget(), QToolBox::insertItem(), QTabBar::insertTab(), QMainWindow::insertToolBar(), QBBSystemLocaleData::installSocketNotifiers(), QNetworkManagerEngine::interfacePropertiesChanged(), QScriptDebugger::interruptAction(), QDeclarativeGridView::itemsRemoved(), QDeclarativeListView::itemsRemoved(), QScriptDebuggerConsoleWidget::keyPressEvent(), QTcpServerConnection::listen(), QUnixSocketServer::listen(), QDeclarativeLoaderPrivate::load(), QDeclarativeAnimatedImage::load(), QPatternist::AccelTreeResourceLoader::load(), QDeclarativeDataLoader::load(), loadDocument(), QHostInfo::lookupHost(), QDeclarativeAnimatedImage::movieRequestFinished(), QDeclarativeDataLoader::networkReplyFinished(), QNetworkManagerEngine::newAccessPoint(), QTcpServerConnection::newConnection(), QNetworkManagerEngine::newConnection(), QVNCServer::newConnection(), QWSPcMouseHandlerPrivate::notify(), QScriptDBusConnection::objectRegisteredAt(), QNetworkAccessFileBackend::open(), QPrintPreviewDialog::open(), QColorDialog::open(), QFontDialog::open(), QProgressDialog::open(), QAudioInputPrivate::open(), QPrintDialog::open(), QMessageBox::open(), QInputDialog::open(), QTipLabel::placeTip(), QStyleSheetStyle::polish(), QToolButtonPrivate::popupTimerDone(), QNetworkAccessHttpBackend::postRequest(), QConnmanEngine::propertyChangedContext(), QAuBucketQWS::QAuBucketQWS(), QAudioInput::QAudioInput(), QAudioInputPrivate::QAudioInputPrivate(), QAudioOutput::QAudioOutput(), QtMultimediaInternal::QAudioOutputBuffer::QAudioOutputBuffer(), QAudioOutputPrivate::QAudioOutputPrivate(), QAuServerNAS::QAuServerNAS(), QAuServerQWS::QAuServerQWS(), QAuthDevice::QAuthDevice(), QAxScript::QAxScript(), QAxSelect::QAxSelect(), QBalloonTip::QBalloonTip(), QBBIntegration::QBBIntegration(), QByteDeviceWrappingIoDevice::QByteDeviceWrappingIoDevice(), QCalendarWidget::QCalendarWidget(), QColorShower::QColorShower(), QComboBoxPrivateContainer::QComboBoxPrivateContainer(), QCoreWlanEngine::QCoreWlanEngine(), QDBusAbstractInterface::QDBusAbstractInterface(), QDBusConnectionInterface::QDBusConnectionInterface(), qDBusRealAddWatch(), QDBusServer::QDBusServer(), QDeclarativeContents::QDeclarativeContents(), QDeclarativeDebugConnectionPrivate::QDeclarativeDebugConnectionPrivate(), QDeclarativeEngineDebugService::QDeclarativeEngineDebugService(), QDeclarativeFolderListModel::QDeclarativeFolderListModel(), QDeclarativeInclude::QDeclarativeInclude(), QDeclarativePixmapReader::QDeclarativePixmapReader(), QDeclarativeTimer::QDeclarativeTimer(), QmlJSDebugger::QDeclarativeViewInspector::QDeclarativeViewInspector(), QDeclarativeWatchProxy::QDeclarativeWatchProxy(), QDeclarativeWorkerScriptEngine::QDeclarativeWorkerScriptEngine(), QDeclarativeXmlQueryEngine::QDeclarativeXmlQueryEngine(), QDirectFBKeyboardHandlerPrivate::QDirectFBKeyboardHandlerPrivate(), QDirectFBMouseHandlerPrivate::QDirectFBMouseHandlerPrivate(), QDirectFBScreenPrivate::QDirectFBScreenPrivate(), QDnotifyFileSystemWatcherEngine::QDnotifyFileSystemWatcherEngine(), QErrorMessage::QErrorMessage(), QExpandingLineEdit::QExpandingLineEdit(), QFbScreen::QFbScreen(), QFileInfoGatherer::QFileInfoGatherer(), QFontComboBox::QFontComboBox(), QFtp::QFtp(), QFtpDTP::QFtpDTP(), QFtpPI::QFtpPI(), QHostInfoLookupManager::QHostInfoLookupManager(), QInputDialogDoubleSpinBox::QInputDialogDoubleSpinBox(), QInputDialogSpinBox::QInputDialogSpinBox(), QIntMouseHandler::QIntMouseHandler(), QPatternist::QIODeviceDelegate::QIODeviceDelegate(), QLinuxInputKeyboardHandler::QLinuxInputKeyboardHandler(), QLinuxInputMouseHandler::QLinuxInputMouseHandler(), QMdiSubWindow::QMdiSubWindow(), QmlApplicationViewer::QmlApplicationViewer(), QmlJSDebugger::QmlToolBar::QmlToolBar(), QMovie::QMovie(), QMultiInputContext::QMultiInputContext(), QNativeWifiEngine::QNativeWifiEngine(), QNetworkConfigurationManager::QNetworkConfigurationManager(), QNetworkManagerEngine::QNetworkManagerEngine(), QNetworkManagerInterface::QNetworkManagerInterface(), QNetworkSession::QNetworkSession(), QNlaEngine::QNlaEngine(), QNonContiguousByteDeviceBufferImpl::QNonContiguousByteDeviceBufferImpl(), QNonContiguousByteDeviceIoDeviceImpl::QNonContiguousByteDeviceIoDeviceImpl(), QScriptEnginePrivate::qobjectData(), QPacketProtocolPrivate::QPacketProtocolPrivate(), QPageSetupWidget::QPageSetupWidget(), QPaintBufferResource::QPaintBufferResource(), QPrintPropertiesDialog::QPrintPropertiesDialog(), QQnxMouseHandler::QQnxMouseHandler(), QScriptBreakpointsWidget::QScriptBreakpointsWidget(), QScriptDebuggerCodeFinderWidget::QScriptDebuggerCodeFinderWidget(), QScriptDebuggerCodeView::QScriptDebuggerCodeView(), QScriptDebuggerConsoleWidget::QScriptDebuggerConsoleWidget(), QScriptEdit::QScriptEdit(), QScriptNewBreakpointWidget::QScriptNewBreakpointWidget(), QShortcut::QShortcut(), QSingleShotTimer::QSingleShotTimer(), QSmoothedAnimation::QSmoothedAnimation(), QSortFilterProxyModel::QSortFilterProxyModel(), QStackedWidget::QStackedWidget(), QSvgWidget::QSvgWidget(), qt_create_commandline(), QToolBarLayout::QToolBarLayout(), QToolButton::QToolButton(), QTreeWidget::QTreeWidget(), QTsLibMouseHandler::QTsLibMouseHandler(), QUndoModel::QUndoModel(), QUnixPrintWidgetPrivate::QUnixPrintWidgetPrivate(), QUnixSocketPrivate::QUnixSocketPrivate(), QVFbKeyboardHandler::QVFbKeyboardHandler(), QVFbMouseHandler::QVFbMouseHandler(), QVFbScreenKeyboardHandler::QVFbScreenKeyboardHandler(), QVFbScreenMouseHandler::QVFbScreenMouseHandler(), QVFbScreenPrivate::QVFbScreenPrivate(), QWaylandDisplay::QWaylandDisplay(), QWhatsThis::QWhatsThis(), QWhatsThisAction::QWhatsThisAction(), QWizardPage::QWizardPage(), QWorkspaceChild::QWorkspaceChild(), QWSClient::QWSClient(), QWSIntKbPrivate::QWSIntKbPrivate(), QWSKbPrivate::QWSKbPrivate(), QWSLinuxInputKbPrivate::QWSLinuxInputKbPrivate(), QWSLinuxInputMousePrivate::QWSLinuxInputMousePrivate(), QWSLinuxTPMouseHandlerPrivate::QWSLinuxTPMouseHandlerPrivate(), QWSQnxKeyboardHandler::QWSQnxKeyboardHandler(), QWSSocket::QWSSocket(), QWSSoundServerClient::QWSSoundServerClient(), QWSTslibMouseHandlerPrivate::QWSTslibMouseHandlerPrivate(), QWSTtyKbPrivate::QWSTtyKbPrivate(), QWSUmKeyboardHandlerPrivate::QWSUmKeyboardHandlerPrivate(), QXcbConnection::QXcbConnection(), QXlibScreen::QXlibScreen(), QCopChannel::registerChannel(), QAbstractTextDocumentLayout::registerHandler(), QDBusConnectionPrivate::registerObject(), QTransportAuth::registerPolicyReceiver(), QWSDisplay::Data::reinit(), QDeclarativeXmlListModel::reload(), QAbstractScrollAreaPrivate::replaceScrollBar(), QDeclarativeXMLHttpRequest::requestFromUrl(), QWidgetAction::requestWidget(), QAlphaWidget::run(), QInotifyFileSystemWatcherEngine::run(), QDnotifySignalThread::run(), QPollingFileSystemWatcherEngine::run(), QRollEffect::run(), QScriptDebugger::runToCursorAction(), QScriptDebugger::runToNewScriptAction(), QDeclarativeListView::sectionCriteria(), QmlJSDebugger::LiveSelectionTool::selectedItemsChanged(), QSidebar::selectUrl(), QHttpNetworkConnectionChannel::sendRequest(), QDBusConnectionPrivate::sendWithReply(), QDBusConnectionPrivate::sendWithReplyAsync(), ShaderEffectItem::setActive(), QUndoGroup::setActiveStack(), QDeclarativeBehavior::setAnimation(), AVMediaObject::setAudioOutput(), QDBusAbstractAdaptor::setAutoRelaySignals(), QScriptEngineDebugger::setAutoShowStandardWindow(), QDeclarativeFlipable::setBack(), QScriptBreakpointsWidget::setBreakpointsModel(), QScriptDebuggerCodeWidget::setBreakpointsModel(), QDBusConnectionPrivate::setBusService(), QCalendarPopup::setCalendarWidget(), QProgressDialog::setCancelButton(), QAuthDevice::setClient(), QScriptDebugger::setCodeFinderWidget(), QLineEdit::setCompleter(), QNetworkManagerInterfaceAccessPoint::setConnections(), QNetworkManagerInterfaceDevice::setConnections(), QNetworkManagerInterfaceDeviceWired::setConnections(), QNetworkManagerInterfaceDeviceWireless::setConnections(), QNetworkManagerSettingsConnection::setConnections(), QNetworkManagerConnectionActive::setConnections(), QScriptDebugger::setConsoleWidget(), QTextControlPrivate::setContent(), QScriptDebuggerCodeWidget::setCurrentScript(), QDeclarativeTextEdit::setCursorDelegate(), QMenuBar::setDefaultAction(), QSyntaxHighlighter::setDocument(), QPPDOptionsEditor::setEditorData(), QUrlModel::setFileSystemModel(), QUndoView::setGroup(), QTreeView::setHeader(), QTableView::setHorizontalHeader(), QDataWidgetMapper::setItemDelegate(), QAbstractItemView::setItemDelegate(), QAbstractItemView::setItemDelegateForColumn(), QAbstractItemView::setItemDelegateForRow(), QComboBoxPrivateContainer::setItemView(), QAbstractSpinBox::setLineEdit(), QComboBox::setLineEdit(), QScriptDebuggerLocalsWidget::setLocalsModel(), QSignalMapper::setMapping(), QPushButton::setMenu(), QDeclarativeRepeater::setModel(), QTableView::setModel(), QDataWidgetMapper::setModel(), QTreeView::setModel(), QHeaderView::setModel(), QDeclarativePathView::setModel(), QCompleter::setModel(), QDeclarativeGridView::setModel(), QAbstractItemView::setModel(), QDeclarativeListView::setModel(), QDeclarativeVisualDataModel::setModel(), QComboBox::setModel(), QLabel::setMovie(), QMenuPrivate::setOverrideMenuAction(), QWizard::setPage(), QDeclarativePathView::setPath(), QCompleter::setPopup(), QmlOstPlugin::setPort(), QFileDialog::setProxyModel(), QColumnView::setResizeGripsVisible(), QDeclarativeAbstractAnimation::setRunning(), QGraphicsView::setScene(), QScriptDebuggerCodeWidget::setScriptsModel(), QScriptDebuggerScriptsWidget::setScriptsModel(), QScriptDebugger::setScriptsWidget(), QWorkspace::setScrollBarsEnabled(), QmlJSDebugger::QDeclarativeViewInspectorPrivate::setSelectedItemsForTools(), QTreeView::setSelectionModel(), QAbstractItemView::setSelectionModel(), QMenu::setSeparatorsCollapsible(), QHttpPrivate::setSock(), QUnixSocket::setSocketDescriptor(), QTableView::setSortingEnabled(), QTreeView::setSortingEnabled(), QDeclarativeFontLoader::setSource(), ShaderEffectItem::setSource(), ShaderEffectSource::setSourceItem(), QAbstractProxyModel::setSourceModel(), QIdentityProxyModel::setSourceModel(), QSortFilterProxyModel::setSourceModel(), QCompletionModel::setSourceModel(), QUndoModel::setStack(), QScriptDebuggerStackWidget::setStackModel(), QScriptDebugger::setStackWidget(), QTabWidget::setTabBar(), QTabWidget::setTabsClosable(), QTabBar::setTabsClosable(), QGraphicsItemAnimation::setTimeLine(), QListWidgetPrivate::setup(), QTableWidgetPrivate::setup(), QPrintPreviewDialogPrivate::setupActions(), QPrintDialogPrivate::setupDestination(), QDeviceClosedNotifier::setupDevice(), QPrintDialogPrivate::setupOptions(), QPrintDialogPrivate::setupPaper(), QPrintDialogPrivate::setupPrinterSettings(), QFtpDTP::setupSocket(), QDesktopServices::setUrlHandler(), QToolBarLayout::setUsePopupMenu(), QTableView::setVerticalHeader(), QMdiAreaPrivate::setViewMode(), QGraphicsProxyWidgetPrivate::setWidget_helper(), ShaderEffectItem::ShaderEffectItem(), QSidebar::showContextMenu(), QWorkspacePrivate::showMaximizeControls(), QStatusBar::showMessage(), QScriptEngineDebugger::standardWindow(), QBBNavigatorEventNotifier::start(), QBBButtonEventNotifier::start(), QNetworkConfigurationManagerPrivate::startPolling(), QProcessPrivate::startProcess(), QHttpThreadDelegate::startRequest(), QJSDebugService::statusChanged(), QScriptDebugger::stepIntoAction(), QScriptDebugger::stepOutAction(), QScriptDebugger::stepOverAction(), QStyleSheetStyle::styleRules(), QPSQLDriver::subscribeToNotificationImplementation(), QXcbConnection::sync(), QNetworkSessionPrivateImpl::syncStateWithInterface(), QGraphicsTextItemPrivate::textControl(), QCoreFuriCuri::timerEvent(), QScriptDebugger::toggleBreakpointAction(), QmlJSDebugger::ToolBarColorBox::ToolBarColorBox(), QNetworkConfigurationManagerPrivate::updateConfigurations(), QDeclarativeGridViewPrivate::updateTrackedItem(), QComboBoxPrivate::viewContainer(), QGraphicsView::viewportEvent(), QNetworkSession::waitForOpened(), QDeclarativeBasePositionerPrivate::watchChanges(), QmlJSDebugger::ZoomTool::ZoomTool(), and QVFbScreenPrivate::~QVFbScreenPrivate().

{
    {
        const void *cbdata[] = { sender, signal, receiver, method, &type };
        if (QInternal::activateCallbacks(QInternal::ConnectCallback, (void **) cbdata))
            return true;
    }

#ifndef QT_NO_DEBUG
    bool warnCompat = true;
#endif
    if (type == Qt::AutoCompatConnection) {
        type = Qt::AutoConnection;
#ifndef QT_NO_DEBUG
        warnCompat = false;
#endif
    }

    if (sender == 0 || receiver == 0 || signal == 0 || method == 0) {
        qWarning("QObject::connect: Cannot connect %s::%s to %s::%s",
                 sender ? sender->metaObject()->className() : "(null)",
                 (signal && *signal) ? signal+1 : "(null)",
                 receiver ? receiver->metaObject()->className() : "(null)",
                 (method && *method) ? method+1 : "(null)");
        return false;
    }
    QByteArray tmp_signal_name;

    if (!check_signal_macro(sender, signal, "connect", "bind"))
        return false;
    const QMetaObject *smeta = sender->metaObject();
    const char *signal_arg = signal;
    ++signal; //skip code
    int signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, false);
    if (signal_index < 0) {
        // check for normalized signatures
        tmp_signal_name = QMetaObject::normalizedSignature(signal - 1);
        signal = tmp_signal_name.constData() + 1;

        smeta = sender->metaObject();
        signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, false);
    }
    if (signal_index < 0) {
        // re-use tmp_signal_name and signal from above

        smeta = sender->metaObject();
        signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, true);
    }
    if (signal_index < 0) {
        err_method_notfound(sender, signal_arg, "connect");
        err_info_about_objects("connect", sender, receiver);
        return false;
    }
    signal_index = QMetaObjectPrivate::originalClone(smeta, signal_index);
    int signalOffset, methodOffset;
    computeOffsets(smeta, &signalOffset, &methodOffset);
    int signal_absolute_index = signal_index + methodOffset;
    signal_index += signalOffset;

    QByteArray tmp_method_name;
    int membcode = extract_code(method);

    if (!check_method_code(membcode, receiver, method, "connect"))
        return false;
    const char *method_arg = method;
    ++method; // skip code

    const QMetaObject *rmeta = receiver->metaObject();
    int method_index_relative = -1;
    switch (membcode) {
    case QSLOT_CODE:
        method_index_relative = QMetaObjectPrivate::indexOfSlotRelative(&rmeta, method, false);
        break;
    case QSIGNAL_CODE:
        method_index_relative = QMetaObjectPrivate::indexOfSignalRelative(&rmeta, method, false);
        break;
    }

    if (method_index_relative < 0) {
        // check for normalized methods
        tmp_method_name = QMetaObject::normalizedSignature(method);
        method = tmp_method_name.constData();

        // rmeta may have been modified above
        rmeta = receiver->metaObject();
        switch (membcode) {
        case QSLOT_CODE:
            method_index_relative = QMetaObjectPrivate::indexOfSlotRelative(&rmeta, method, false);
            if (method_index_relative < 0)
                method_index_relative = QMetaObjectPrivate::indexOfSlotRelative(&rmeta, method, true);
            break;
        case QSIGNAL_CODE:
            method_index_relative = QMetaObjectPrivate::indexOfSignalRelative(&rmeta, method, false);
            if (method_index_relative < 0)
                method_index_relative = QMetaObjectPrivate::indexOfSignalRelative(&rmeta, method, true);
            break;
        }
    }

    if (method_index_relative < 0) {
        err_method_notfound(receiver, method_arg, "connect");
        err_info_about_objects("connect", sender, receiver);
        return false;
    }

    if (!QMetaObject::checkConnectArgs(signal, method)) {
        qWarning("QObject::connect: Incompatible sender/receiver arguments"
                 "\n        %s::%s --> %s::%s",
                 sender->metaObject()->className(), signal,
                 receiver->metaObject()->className(), method);
        return false;
    }

    int *types = 0;
    if ((type == Qt::QueuedConnection)
            && !(types = queuedConnectionTypes(smeta->method(signal_absolute_index).parameterTypes())))
        return false;

#ifndef QT_NO_DEBUG
    if (warnCompat) {
        QMetaMethod smethod = smeta->method(signal_absolute_index);
        QMetaMethod rmethod = rmeta->method(method_index_relative + rmeta->methodOffset());
        check_and_warn_compat(smeta, smethod, rmeta, rmethod);
    }
#endif
    if (!QMetaObjectPrivate::connect(sender, signal_index, receiver, method_index_relative, rmeta ,type, types))
        return false;
    const_cast<QObject*>(sender)->connectNotify(signal - 1);
    return true;
}

connect() [2/3]

bool QObject::connect ( const QObject *  sender, const QMetaMethod &  signal, const QObject *  receiver, const QMetaMethod &  method, Qt::ConnectionType  type = Qt::AutoConnection  )

static

Since

4.8

Creates a connection of the given type from the signal in the sender object to the method in the receiver object. Returns true if the connection succeeds; otherwise returns false.

This function works in the same way as connect(const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type) but it uses QMetaMethod to specify signal and method.

See also

connect(const QObject *sender, const char *signal, const QObject *receiver, const char *method, Qt::ConnectionType type)

Definition at line 2730 of file qobject.cpp.

{
#ifndef QT_NO_DEBUG
    bool warnCompat = true;
#endif
    if (type == Qt::AutoCompatConnection) {
        type = Qt::AutoConnection;
#ifndef QT_NO_DEBUG
        warnCompat = false;
#endif
    }

    if (sender == 0
            || receiver == 0
            || signal.methodType() != QMetaMethod::Signal
            || method.methodType() == QMetaMethod::Constructor) {
        qWarning("QObject::connect: Cannot connect %s::%s to %s::%s",
                 sender ? sender->metaObject()->className() : "(null)",
                 signal.signature(),
                 receiver ? receiver->metaObject()->className() : "(null)",
                 method.signature() );
        return false;
    }

    QVarLengthArray<char> signalSignature;
    QObjectPrivate::signalSignature(signal, &signalSignature);

    {
        QByteArray methodSignature;
        methodSignature.reserve(qstrlen(method.signature())+1);
        methodSignature.append((char)(method.methodType() == QMetaMethod::Slot ? QSLOT_CODE
                                    : method.methodType() == QMetaMethod::Signal ? QSIGNAL_CODE : 0  + '0'));
        methodSignature.append(method.signature());
        const void *cbdata[] = { sender, signalSignature.constData(), receiver, methodSignature.constData(), &type };
        if (QInternal::activateCallbacks(QInternal::ConnectCallback, (void **) cbdata))
            return true;
    }


    int signal_index;
    int method_index;
    {
        int dummy;
        QMetaObjectPrivate::memberIndexes(sender, signal, &signal_index, &dummy);
        QMetaObjectPrivate::memberIndexes(receiver, method, &dummy, &method_index);
    }

    const QMetaObject *smeta = sender->metaObject();
    const QMetaObject *rmeta = receiver->metaObject();
    if (signal_index == -1) {
        qWarning("QObject::connect: Can't find signal %s on instance of class %s",
                 signal.signature(), smeta->className());
        return false;
    }
    if (method_index == -1) {
        qWarning("QObject::connect: Can't find method %s on instance of class %s",
                 method.signature(), rmeta->className());
        return false;
    }

    if (!QMetaObject::checkConnectArgs(signal.signature(), method.signature())) {
        qWarning("QObject::connect: Incompatible sender/receiver arguments"
                 "\n        %s::%s --> %s::%s",
                 smeta->className(), signal.signature(),
                 rmeta->className(), method.signature());
        return false;
    }

    int *types = 0;
    if ((type == Qt::QueuedConnection)
            && !(types = queuedConnectionTypes(signal.parameterTypes())))
        return false;

#ifndef QT_NO_DEBUG
    if (warnCompat)
        check_and_warn_compat(smeta, signal, rmeta, method);
#endif
    if (!QMetaObjectPrivate::connect(sender, signal_index, receiver, method_index, 0, type, types))
        return false;

    const_cast<QObject*>(sender)->connectNotify(signalSignature.constData());
    return true;
}

connect() [3/3]

bool QObject::connect ( const QObject *  sender, const char *  signal, const char *  member, Qt::ConnectionType  type = Qt::AutoConnection  ) const

inline

Definition at line 337 of file qobject.h.

{ return connect(asender, asignal, this, amember, atype); }

connectNotify()

void QObject::connectNotify ( const char *  signal )

protectedvirtual

This virtual function is called when something has been connected to signal in this object.

If you want to compare signal with a specific signal, use QLatin1String and the SIGNAL() macro as follows:

if (QLatin1String(signal) == SIGNAL(valueChanged(int))) {
    // signal is valueChanged(int)
}

If the signal contains multiple parameters or parameters that contain spaces, call QMetaObject::normalizedSignature() on the result of the SIGNAL() macro.

Warning

This function violates the object-oriented principle of modularity. However, it might be useful when you need to perform expensive initialization only if something is connected to a signal.

See also

connect(), disconnectNotify()

Reimplemented in QOfonoSmsInterface, QOfonoPrimaryDataContextInterface, QConnmanAgentInterface, QOfonoDataConnectionManagerInterface, QConnmanTechnologyInterface, QOfonoSimInterface, QConnmanServiceInterface, QOfonoNetworkOperatorInterface, QOfonoNetworkRegistrationInterface, QConnmanProfileInterface, QOfonoModemInterface, QConnmanManagerInterface, QDBusAbstractInterface, QNetworkSession, QOfonoManagerInterface, QFutureWatcherBase, QClipboard, QAxWidget, QBuffer, and QAxObject.

Definition at line 3142 of file qobject.cpp.

Referenced by connect(), and QNetworkSession::connectNotify().

{
}

customEvent()

void QObject::customEvent ( QEvent *  )

protectedvirtual

This event handler can be reimplemented in a subclass to receive custom events.

Custom events are user-defined events with a type value at least as large as the QEvent::User item of the QEvent::Type enum, and is typically a QEvent subclass. The event is passed in the event parameter.

See also

event(), QEvent

Reimplemented in QDBusConnectionPrivate.

Definition at line 1346 of file qobject.cpp.

Referenced by event().

{
}

deleteLater

void QObject::deleteLater ( )

slot

Schedules this object for deletion.

The object will be deleted when control returns to the event loop. If the event loop is not running when this function is called (e.g. deleteLater() is called on an object before QCoreApplication::exec()), the object will be deleted once the event loop is started. If deleteLater() is called after the main event loop has stopped, the object will not be deleted. Since Qt 4.8, if deleteLater() is called on an object that lives in a thread with no running event loop, the object will be destroyed when the thread finishes.

Note that entering and leaving a new event loop (e.g., by opening a modal dialog) will not perform the deferred deletion; for the object to be deleted, the control must return to the event loop from which deleteLater() was called.

Note: It is safe to call this function more than once; when the first deferred deletion event is delivered, any pending events for the object are removed from the event queue.

See also

destroyed(), QPointer

Definition at line 2145 of file qobject.cpp.

Referenced by QWSServerPrivate::_q_clientClosed(), QScriptDebuggerLocalsWidgetPrivate::_q_onCompletionTaskFinished(), QScriptDebuggerConsoleWidgetPrivate::_q_onCompletionTaskFinished(), QToolBoxPrivate::_q_widgetDestroyed(), QUnixSocket::abort(), QHttpThreadDelegate::abortRequest(), QLocalServerPrivate::addListener(), QNetworkConfigurationManagerPrivate::cleanup(), QDeclarativeLoaderPrivate::clear(), QGraphicsWidget::close(), QColumnViewPrivate::closeColumns(), connManager(), QWidgetAction::deleteWidget(), QDBusConnectionPrivate::deleteYourself(), QDeclarativeObjectScriptClass::destroy(), QDeclarativeXMLHttpRequest::destroyNetwork(), QDeferredGraphicsSystemChange::doChange(), doDeleteLater(), QDragManager::drag(), QOleDropTarget::Drop(), QScriptEdit::extraAreaMouseEvent(), QDeclarativeInclude::finished(), QTipLabel::hideTipImmediately(), QDeclarativeDataLoader::networkReplyFinished(), QDeclarativePixmapReader::networkRequestDone(), QNetworkAccessHttpBackend::postRequest(), QDeclarativePixmapReader::processJobs(), qFadeEffect(), qScrollEffect(), QWSSoundServerClient::QWSSoundServerClient(), QDeclarativeVisualDataModel::release(), QAbstractItemViewPrivate::releaseEditor(), QNetworkManagerEngine::removeConnection(), QBBIntegration::removeDisplay(), QAlphaWidget::render(), QDeclarativeFontObject::replyFinished(), QRollEffect::scroll(), QMainWindow::setMenuBar(), QAbstractItemView::setModel(), QColumnView::setResizeGripsVisible(), QDeclarativeConnections::setTarget(), QToolBarLayout::takeAt(), QWidget::update(), QX11Data::xdndHandleBadwindow(), QDeclarativePixmapReader::~QDeclarativePixmapReader(), QDeclarativeWorkerScriptEngine::~QDeclarativeWorkerScriptEngine(), QDeclarativeXmlQueryEngine::~QDeclarativeXmlQueryEngine(), QEventDispatcherMac::~QEventDispatcherMac(), and QScriptEngineDebuggerBackendPrivate::~QScriptEngineDebuggerBackendPrivate().

{
    QCoreApplication::postEvent(this, new QEvent(QEvent::DeferredDelete));
}

destroyed

QObject::destroyed ( QObject *  obj = 0 )

signal

This signal is emitted immediately before the object obj is destroyed, and can not be blocked.

All the objects's children are destroyed immediately after this signal is emitted.

See also

deleteLater(), QPointer

Referenced by QObjectCleanupHandler::add(), QDeclarativeAnchorsPrivate::addDepend(), QWizardPrivate::addField(), QAxScriptManager::addObject(), QGLShaderProgram::addShader(), QDialogButtonBox::clear(), QDBusConnectionPrivate::connectSignal(), connManager(), QSoftKeyManager::createAction(), QmlJSDebugger::BoundingRectHighlighter::createBoundingBox(), QSoftKeyManager::createKeyedAction(), QDeclarativeData::destroyed(), QVGPaintEngine::drawCachedGlyphs(), QAbstractItemViewPrivate::editor(), QGLWindowSurface::hijackWindow(), QAuServerNAS::init(), QStyleSheetStyle::initWidget(), QToolBox::insertItem(), QTipLabel::placeTip(), QBalloonTip::QBalloonTip(), QDeclarativePixmapReader::QDeclarativePixmapReader(), QDeclarativeXmlQueryEngine::QDeclarativeXmlQueryEngine(), QHostInfoLookupManager::QHostInfoLookupManager(), QAbstractTextDocumentLayout::registerHandler(), QDBusConnectionPrivate::registerObject(), QWidgetAction::releaseWidget(), QDeclarativeAnchorsPrivate::remDepend(), QObjectCleanupHandler::remove(), QDialogButtonBox::removeButton(), QWizardPrivate::removeFieldAt(), QToolBox::removeItem(), QGLShaderProgram::removeShader(), QWidgetAction::requestWidget(), QTipLabel::reuseTip(), QAuthDevice::setClient(), QMenuBar::setDefaultAction(), QComboBoxPrivateContainer::setItemView(), QSignalMapper::setMapping(), QDataWidgetMapper::setModel(), QAbstractItemView::setModel(), QComboBox::setModel(), QMenuPrivate::setOverrideMenuAction(), QmlJSDebugger::QDeclarativeViewInspectorPrivate::setSelectedItemsForTools(), QAbstractProxyModel::setSourceModel(), QCompletionModel::setSourceModel(), QUndoModel::setStack(), QDesktopServices::setUrlHandler(), QGraphicsProxyWidgetPrivate::setWidget_helper(), QComboBox::~QComboBox(), QGraphicsProxyWidget::~QGraphicsProxyWidget(), ~QObject(), and QWidgetAction::~QWidgetAction().

disconnect() [1/4]

bool QObject::disconnect ( const QObject *  sender, const char *  signal, const QObject *  receiver, const char *  method  )

static

Disconnects signal in object sender from method in object receiver.

Note

This class or function is threadsafe.

Returns true if the connection is successfully broken; otherwise returns false.

A signal-slot connection is removed when either of the objects involved are destroyed.

disconnect() is typically used in three ways, as the following examples demonstrate.

1. Disconnect everything connected to an object's signals:

   disconnect(myObject, 0, 0, 0);

   equivalent to the non-static overloaded function

   myObject->disconnect();

2. Disconnect everything connected to a specific signal:

   disconnect(myObject, SIGNAL(mySignal()), 0, 0);

   equivalent to the non-static overloaded function

   myObject->disconnect(SIGNAL(mySignal()));

3. Disconnect a specific receiver:

   disconnect(myObject, 0, myReceiver, 0);

   equivalent to the non-static overloaded function

   myObject->disconnect(myReceiver);

0 may be used as a wildcard, meaning "any signal", "any receiving object", or "any slot in the receiving object", respectively.

The sender may never be 0. (You cannot disconnect signals from more than one object in a single call.)

If signal is 0, it disconnects receiver and method from any signal. If not, only the specified signal is disconnected.

If receiver is 0, it disconnects anything connected to signal. If not, slots in objects other than receiver are not disconnected.

If method is 0, it disconnects anything that is connected to receiver. If not, only slots named method will be disconnected, and all other slots are left alone. The method must be 0 if receiver is left out, so you cannot disconnect a specifically-named slot on all objects.

See also

connect()

Definition at line 2895 of file qobject.cpp.

Referenced by QStateMachinePrivate::_q_animationFinished(), QNetworkReplyImplPrivate::_q_bufferOutgoingDataFinished(), QMessageBoxPrivate::_q_buttonClicked(), QProgressDialogPrivate::_q_disconnectOnClose(), QNetworkAccessManagerPrivate::_q_networkSessionClosed(), QScriptDebuggerLocalsWidgetPrivate::_q_onCompletionTaskFinished(), QNetworkReplyImpl::abort(), QToolButton::actionEvent(), QMenuBar::actionEvent(), QMenu::actionEvent(), _IapAddTimer::add(), QMainWindow::addToolBar(), QStateMachinePrivate::applyProperties(), QNetworkSessionPrivateImpl::cleanupSession(), QDeclarativePixmap::clear(), QDialogButtonBox::clear(), QLabelPrivate::clearContents(), QNetworkReplyImpl::close(), QPSQLDriver::close(), QNetworkReplyImplPrivate::completeCacheSave(), QDeclarativeView::continueExecute(), QLineControl::copy(), QNetworkAccessManagerPrivate::createSession(), QNetworkSessionPrivateImpl::decrementTimeout(), QDeclarativeXmlListModelPrivate::deleteReply(), QDeclarativeCompiledBindingsPrivate::Binding::destroy(), QDeclarativeXMLHttpRequest::destroyNetwork(), QVistaHelper::disconnectBackButton(), QNetworkAccessFtpBackend::disconnectFromFtp(), QProxyModel::disconnectFromModel(), ShaderEffectItem::disconnectPropertySignals(), QMdiAreaPrivate::disconnectSubWindow(), QAnimationGroupPrivate::disconnectUncontrolledAnimation(), QAbstractPageSetupDialog::done(), QPrintPreviewDialog::done(), QPrintDialog::done(), QFontDialog::done(), QColorDialog::done(), QInputDialog::done(), QNetworkAccessCache::emitEntryReady(), QDeclarativeInclude::finished(), QLineEdit::focusOutEvent(), QNetworkSessionManagerPrivate::forceSessionClose(), QmlJSDebugger::BoundingRectHighlighter::freeBoundingBox(), QNetworkAccessFtpBackend::ftpDone(), QDBusConnectionPrivate::objectDestroyed(), QScriptDBusConnection::objectRegisteredAt(), QToolButtonPrivate::popupTimerDone(), QDeclarativeDebugConnectionPrivate::readyRead(), QPacketProtocolPrivate::readyToRead(), QDBusConnectionPrivate::registerObject(), QAbstractItemViewPrivate::releaseEditor(), QDeclarativeGridViewPrivate::releaseItem(), QWidgetAction::releaseWidget(), QDeclarativeAnchorsPrivate::remDepend(), QObjectCleanupHandler::remove(), QActionGroup::removeAction(), QDialogButtonBox::removeButton(), QConnmanEngine::removeConfiguration(), QWizardPrivate::removeFieldAt(), QToolBox::removeItem(), QGLShaderProgram::removeShader(), QMainWindowLayout::removeToolBar(), QAbstractSocketPrivate::resetSocketLayer(), QTipLabel::reuseTip(), QmlJSDebugger::LiveSelectionTool::selectedItemsChanged(), QSidebar::selectUrl(), QHttpNetworkConnectionChannel::sendRequest(), ShaderEffectItem::setActive(), QUndoGroup::setActiveStack(), AVMediaObject::setAudioOutput(), QDBusAbstractAdaptor::setAutoRelaySignals(), QScriptEngineDebugger::setAutoShowStandardWindow(), QNetworkReplyImplPrivate::setCachingEnabled(), QScriptDebugger::setCodeFinderWidget(), QLineEdit::setCompleter(), QScriptDebugger::setConsoleWidget(), QMenuBar::setDefaultAction(), QSyntaxHighlighter::setDocument(), QUrlModel::setFileSystemModel(), QUndoView::setGroup(), QInputDialogPrivate::setInputWidget(), QDataWidgetMapper::setItemDelegate(), QAbstractItemView::setItemDelegate(), QAbstractItemView::setItemDelegateForColumn(), QAbstractItemView::setItemDelegateForRow(), QComboBoxPrivateContainer::setItemView(), QScriptDebuggerLocalsWidget::setLocalsModel(), QDeclarativeRepeater::setModel(), QTableView::setModel(), QDataWidgetMapper::setModel(), QTreeView::setModel(), QHeaderView::setModel(), QDeclarativePathView::setModel(), QDeclarativeGridView::setModel(), QAbstractItemView::setModel(), QDeclarativeListView::setModel(), QDeclarativeVisualDataModel::setModel(), QComboBox::setModel(), QMenuPrivate::setOverrideMenuAction(), QDeclarativePathView::setPath(), QCompleter::setPopup(), QGraphicsView::setScene(), QScriptDebugger::setScriptsWidget(), QmlJSDebugger::QDeclarativeViewInspectorPrivate::setSelectedItemsForTools(), QTreeView::setSelectionModel(), QAbstractItemView::setSelectionModel(), QHttpPrivate::setSock(), QTableView::setSortingEnabled(), QTreeView::setSortingEnabled(), ShaderEffectSource::setSourceItem(), QAbstractProxyModel::setSourceModel(), QIdentityProxyModel::setSourceModel(), QSortFilterProxyModel::setSourceModel(), QCompletionModel::setSourceModel(), QUndoModel::setStack(), QScriptDebugger::setStackWidget(), QTabWidget::setTabsClosable(), QDeviceClosedNotifier::setupDevice(), QToolBarLayout::setUsePopupMenu(), QGraphicsProxyWidgetPrivate::setWidget_helper(), QHttpThreadDelegate::synchronousAuthenticationRequiredSlot(), QHttpThreadDelegate::synchronousProxyAuthenticationRequiredSlot(), QConnmanEngine::technologyPropertyChangedContext(), QStyleSheetStyle::unpolish(), QTransportAuth::unregisterPolicyReceiver(), QPSQLDriver::unsubscribeFromNotificationImplementation(), QDeclarativeBasePositionerPrivate::unwatchChanges(), QDeclarativeGridViewPrivate::updateTrackedItem(), _IapAddTimer::~_IapAddTimer(), Maemo::IcdPrivate::~IcdPrivate(), QAudioInputPrivate::~QAudioInputPrivate(), QAudioOutputPrivate::~QAudioOutputPrivate(), QComboBox::~QComboBox(), QGraphicsProxyWidget::~QGraphicsProxyWidget(), QIntMouseHandler::~QIntMouseHandler(), QVFbScreenPrivate::~QVFbScreenPrivate(), and QWidgetAction::~QWidgetAction().

{
    if (sender == 0 || (receiver == 0 && method != 0)) {
        qWarning("Object::disconnect: Unexpected null parameter");
        return false;
    }

    {
        const void *cbdata[] = { sender, signal, receiver, method };
        if (QInternal::activateCallbacks(QInternal::DisconnectCallback, (void **) cbdata))
            return true;
    }

    const char *signal_arg = signal;
    QByteArray signal_name;
    bool signal_found = false;
    if (signal) {
        QT_TRY {
            signal_name = QMetaObject::normalizedSignature(signal);
            signal = signal_name.constData();
        } QT_CATCH (const std::bad_alloc &) {
            // if the signal is already normalized, we can continue.
            if (sender->metaObject()->indexOfSignal(signal + 1) == -1)
                QT_RETHROW;
        }

        if (!check_signal_macro(sender, signal, "disconnect", "unbind"))
            return false;
        signal++; // skip code
    }

    QByteArray method_name;
    const char *method_arg = method;
    int membcode = -1;
    bool method_found = false;
    if (method) {
        QT_TRY {
            method_name = QMetaObject::normalizedSignature(method);
            method = method_name.constData();
        } QT_CATCH(const std::bad_alloc &) {
            // if the method is already normalized, we can continue.
            if (receiver->metaObject()->indexOfMethod(method + 1) == -1)
                QT_RETHROW;
        }

        membcode = extract_code(method);
        if (!check_method_code(membcode, receiver, method, "disconnect"))
            return false;
        method++; // skip code
    }

    /* We now iterate through all the sender's and receiver's meta
     * objects in order to also disconnect possibly shadowed signals
     * and slots with the same signature.
    */
    bool res = false;
    const QMetaObject *smeta = sender->metaObject();
    do {
        int signal_index = -1;
        if (signal) {
            signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, false);
            if (signal_index < 0)
                signal_index = QMetaObjectPrivate::indexOfSignalRelative(&smeta, signal, true);
            if (signal_index < 0)
                break;
            signal_index = QMetaObjectPrivate::originalClone(smeta, signal_index);
            int signalOffset, methodOffset;
            computeOffsets(smeta, &signalOffset, &methodOffset);
            signal_index += signalOffset;
            signal_found = true;
        }

        if (!method) {
            res |= QMetaObjectPrivate::disconnect(sender, signal_index, receiver, -1);
        } else {
            const QMetaObject *rmeta = receiver->metaObject();
            do {
                int method_index = rmeta->indexOfMethod(method);
                if (method_index >= 0)
                    while (method_index < rmeta->methodOffset())
                            rmeta = rmeta->superClass();
                if (method_index < 0)
                    break;
                res |= QMetaObjectPrivate::disconnect(sender, signal_index, receiver, method_index);
                method_found = true;
            } while ((rmeta = rmeta->superClass()));
        }
    } while (signal && (smeta = smeta->superClass()));

    if (signal && !signal_found) {
        err_method_notfound(sender, signal_arg, "disconnect");
        err_info_about_objects("disconnect", sender, receiver);
    } else if (method && !method_found) {
        err_method_notfound(receiver, method_arg, "disconnect");
        err_info_about_objects("disconnect", sender, receiver);
    }
    if (res)
        const_cast<QObject*>(sender)->disconnectNotify(signal ? (signal - 1) : 0);
    return res;
}

disconnect() [2/4]

bool QObject::disconnect ( const QObject *  sender, const QMetaMethod &  signal, const QObject *  receiver, const QMetaMethod &  method  )

static

Since

4.8

Disconnects signal in object sender from method in object receiver. Returns true if the connection is successfully broken; otherwise returns false.

This function provides the same possibilities like disconnect(const QObject *sender, const char *signal, const QObject *receiver, const char *method) but uses QMetaMethod to represent the signal and the method to be disconnected.

Additionally this function returnsfalse and no signals and slots disconnected if:

signal is not a member of sender class or one of its parent classes.

method is not a member of receiver class or one of its parent classes.

signal instance represents not a signal.

QMetaMethod() may be used as wildcard in the meaning "any signal" or "any slot in receiving object". In the same way 0 can be used for receiver in the meaning "any receiving object". In this case method should also be QMetaMethod(). sender parameter should be never 0.

See also

disconnect(const QObject *sender, const char *signal, const QObject *receiver, const char *method)

Definition at line 3026 of file qobject.cpp.

{
    if (sender == 0 || (receiver == 0 && method.mobj != 0)) {
        qWarning("Object::disconnect: Unexpected null parameter");
        return false;
    }
    if (signal.mobj) {
        if(signal.methodType() != QMetaMethod::Signal) {
            qWarning("Object::%s: Attempt to %s non-signal %s::%s",
                     "disconnect","unbind",
                     sender->metaObject()->className(), signal.signature());
            return false;
        }
    }
    if (method.mobj) {
        if(method.methodType() == QMetaMethod::Constructor) {
            qWarning("QObject::disconect: cannot use constructor as argument %s::%s",
                     receiver->metaObject()->className(), method.signature());
            return false;
        }
    }

    QVarLengthArray<char> signalSignature;
    if (signal.mobj)
        QObjectPrivate::signalSignature(signal, &signalSignature);

    {
        QByteArray methodSignature;
        if (method.mobj) {
            methodSignature.reserve(qstrlen(method.signature())+1);
            methodSignature.append((char)(method.methodType() == QMetaMethod::Slot ? QSLOT_CODE
                                        : method.methodType() == QMetaMethod::Signal ? QSIGNAL_CODE : 0  + '0'));
            methodSignature.append(method.signature());
        }
        const void *cbdata[] = { sender, signal.mobj ? signalSignature.constData() : 0,
                                 receiver, method.mobj ? methodSignature.constData() : 0 };
        if (QInternal::activateCallbacks(QInternal::DisconnectCallback, (void **) cbdata))
            return true;
    }

    int signal_index;
    int method_index;
    {
        int dummy;
        QMetaObjectPrivate::memberIndexes(sender, signal, &signal_index, &dummy);
        QMetaObjectPrivate::memberIndexes(receiver, method, &dummy, &method_index);
    }
    // If we are here sender is not null. If signal is not null while signal_index
    // is -1 then this signal is not a member of sender.
    if (signal.mobj && signal_index == -1) {
        qWarning("QObject::disconect: signal %s not found on class %s",
                 signal.signature(), sender->metaObject()->className());
        return false;
    }
    // If this condition is true then method is not a member of receeiver.
    if (receiver && method.mobj && method_index == -1) {
        qWarning("QObject::disconect: method %s not found on class %s",
                 method.signature(), receiver->metaObject()->className());
        return false;
    }

    if (!QMetaObjectPrivate::disconnect(sender, signal_index, receiver, method_index))
        return false;

    const_cast<QObject*>(sender)->disconnectNotify(method.mobj ? signalSignature.constData() : 0);
    return true;
}

disconnect() [3/4]

bool QObject::disconnect ( const char *  signal = 0, const QObject *  receiver = 0, const char *  member = 0  )

inline

Definition at line 248 of file qobject.h.

        { return disconnect(this, signal, receiver, member); }

disconnect() [4/4]

bool QObject::disconnect ( const QObject *  receiver, const char *  member = 0  )

inline

Definition at line 251 of file qobject.h.

        { return disconnect(this, 0, receiver, member); }

disconnectNotify()

void QObject::disconnectNotify ( const char *  signal )

protectedvirtual

This virtual function is called when something has been disconnected from signal in this object.

See connectNotify() for an example of how to compare signal with a specific signal.

Warning

This function violates the object-oriented principle of modularity. However, it might be useful for optimizing access to expensive resources.

See also

disconnect(), connectNotify()

Reimplemented in QOfonoSmsInterface, QOfonoPrimaryDataContextInterface, QConnmanAgentInterface, QOfonoDataConnectionManagerInterface, QConnmanTechnologyInterface, QOfonoSimInterface, QConnmanServiceInterface, QOfonoNetworkOperatorInterface, QOfonoNetworkRegistrationInterface, QConnmanProfileInterface, QOfonoModemInterface, QConnmanManagerInterface, QDBusAbstractInterface, QNetworkSession, QOfonoManagerInterface, QFutureWatcherBase, and QBuffer.

Definition at line 3162 of file qobject.cpp.

Referenced by disconnect(), and QNetworkSession::disconnectNotify().

{
}

dumpObjectInfo()

void QObject::dumpObjectInfo

(

)

Dumps information about signal connections, etc.

for this object to the debug output.

This function is useful for debugging, but does nothing if the library has been compiled in release mode (i.e. without debugging information).

See also

dumpObjectTree()

Definition at line 3917 of file qobject.cpp.

{
#if defined(QT_DEBUG)
    qDebug("OBJECT %s::%s", metaObject()->className(),
           objectName().isEmpty() ? "unnamed" : objectName().toLocal8Bit().data());

    Q_D(QObject);
    QMutexLocker locker(signalSlotLock(this));

    // first, look for connections where this object is the sender
    qDebug("  SIGNALS OUT");

    if (d->connectionLists) {
        int offset = 0;
        int offsetToNextMetaObject = 0;
        for (int signal_index = 0; signal_index < d->connectionLists->count(); ++signal_index) {
            if (signal_index >= offsetToNextMetaObject) {
                const QMetaObject *mo = metaObject();
                int signalOffset, methodOffset;
                computeOffsets(mo, &signalOffset, &methodOffset);
                while (signalOffset > signal_index) {
                    mo = mo->superClass();
                    offsetToNextMetaObject = signalOffset;
                    computeOffsets(mo, &signalOffset, &methodOffset);
                }
                offset = methodOffset - signalOffset;
            }
            const QMetaMethod signal = metaObject()->method(signal_index + offset);
            qDebug("        signal: %s", signal.signature());

            // receivers
            const QObjectPrivate::Connection *c =
                d->connectionLists->at(signal_index).first;
            while (c) {
                if (!c->receiver) {
                    qDebug("          <Disconnected receiver>");
                    c = c->nextConnectionList;
                    continue;
                }
                const QMetaObject *receiverMetaObject = c->receiver->metaObject();
                const QMetaMethod method = receiverMetaObject->method(c->method());
                qDebug("          --> %s::%s %s",
                       receiverMetaObject->className(),
                       c->receiver->objectName().isEmpty() ? "unnamed" : qPrintable(c->receiver->objectName()),
                       method.signature());
                c = c->nextConnectionList;
            }
        }
    } else {
        qDebug( "        <None>" );
    }

    // now look for connections where this object is the receiver
    qDebug("  SIGNALS IN");

    if (d->senders) {
        for (QObjectPrivate::Connection *s = d->senders; s; s = s->next) {
            const QMetaMethod slot = metaObject()->method(s->method());
            qDebug("          <-- %s::%s  %s",
                   s->sender->metaObject()->className(),
                   s->sender->objectName().isEmpty() ? "unnamed" : qPrintable(s->sender->objectName()),
                   slot.signature());
        }
    } else {
        qDebug("        <None>");
    }
#endif
}

dumpObjectTree()

void QObject::dumpObjectTree

(

)

Dumps a tree of children to the debug output.

This function is useful for debugging, but does nothing if the library has been compiled in release mode (i.e. without debugging information).

See also

dumpObjectInfo()

Definition at line 3901 of file qobject.cpp.

{
    dumpRecursive(0, this);
}

dynamicPropertyNames()

QList< QByteArray > QObject::dynamicPropertyNames

(

)

const

Returns the names of all properties that were dynamically added to the object using setProperty().

Since

4.2

Definition at line 3839 of file qobject.cpp.

Referenced by QScript::QObjectDelegate::getOwnPropertyNames().

{
    Q_D(const QObject);
    if (d->extraData)
        return d->extraData->propertyNames;
    return QList<QByteArray>();
}

event()

bool QObject::event ( QEvent *  e )

virtual

This virtual function receives events to an object and should return true if the event e was recognized and processed.

The event() function can be reimplemented to customize the behavior of an object.

See also

installEventFilter(), timerEvent(), QApplication::sendEvent(), QApplication::postEvent(), QWidget::event()

Reimplemented in QMainWindowTabBar, QExceptionNotifier, QWriteNotifier, QReadNotifier, QCalendarView, QWidget, QGLWidget, QMdi::ControllerWidget, QMdi::ControlLabel, QTreeWidget, QApplication, QMessageBox, QAbstractItemView, QTableWidget, QSettings, QDeclarativePinchArea, QTextEdit, QDeclarativeTextEdit, QListWidget, QWorkspaceTitleBar, QTextControl, QGraphicsScene, QDeclarativeTextInput, QDeclarativeListView, QGraphicsView, QLineEdit, QPlainTextEdit, QComboBox, QAction, QGraphicsWidget, QMainWindow, QDeclarativeGridView, QCoreApplication, QHeaderView, QWizard, QTabBar, QDeclarativeWorkerScriptEnginePrivate, QMenu, QDeclarativePathView, QSplitterHandle, QStateMachine, QDeclarativeItem, QSystemTrayIconSys, QDeclarativeXmlQueryThreadObject, QCalendarPopup, QDateTimeEdit, QTabWidget, QDialogButtonBox, QFileSystemModel, QCalendarWidget, QMdiArea, QToolBar, QCompleter, QStyleSheetStyle, QMenuBar, QListView, QLabel, QAbstractSlider, QSidebar, QAbstractButton, QDeclarativePixmapReaderThreadObject, QAxHostWidget, QFrame, QScriptDebuggerBackendEventReceiver, QAbstractAnimation, QMacStyle, QAbstractSpinBox, QDockWidget, QX11EmbedContainer, QLCDNumber, QSplitter, QDeclarativePixmapReply, QProgressBar, QSystemTrayIcon, QMdiSubWindow, QDeclarativeListModelWorkerAgent, QDeclarativeWorkerScript, QToolButton, QDeclarativeSystemPalette, QTextBrowser, QDialog, QDnotifySignalThread, QClipboard, QState, QSpinBox, QWorkspace, QVariantAnimation, QStatusBar, QToolBox, QAbstractTransition, QMotifStyle, QEventDispatcherWin32, QAbstractScrollArea, QShortcut, QSlider, QProxyStyle, QMDIControl, QFontComboBox, QGraphicsSceneBspTreeIndex, QSoftKeyManager, QGroupBox, QPushButton, QWindowsVistaStyle, QDial, QNetworkReplyImpl, QStackedWidget, QScriptDebuggerCodeView, QScriptEditExtraArea, QFutureWatcherBase, QScrollArea, QSplashScreen, QWinEventNotifier, QGraphicsProxyWidget, QHistoryState, QAbstractState, QRubberBand, QCheckBox, QSocketNotifier, QX11EmbedWidget, QSequentialAnimationGroup, QEventTransition, QSignalTransition, QAnimationGroup, QPropertyAnimation, QSizeGrip, QScriptDebuggerFrontendEventReceiver, QWidgetAction, QCommandLinkButton, QPauseAnimation, QParallelAnimationGroup, QRadioButton, QScrollBar, QFinalState, QFocusFrame, and QMacNativeWidget.

Definition at line 1200 of file qobject.cpp.

Referenced by QWSServerPrivate::_q_newConnection(), QEventDispatcherUNIX::activateSocketNotifiers(), QDeclarativeDebugTrace::addEventImpl(), QDeclarativeState::apply(), clipboardData(), QGestureManager::deliverEvents(), QStyleSheetStyle::deref(), QBBBpsEventFilter::dispatcherEventFilter(), QStyledItemDelegate::editorEvent(), QItemDelegate::editorEvent(), QBBInputContext::endComposition(), QSocketNotifier::event(), QAbstractState::event(), QWinEventNotifier::event(), QFutureWatcherBase::event(), QNetworkReplyImpl::event(), QWindowsVistaStyle::event(), QGraphicsSceneBspTreeIndex::event(), QEventDispatcherWin32::event(), QAbstractTransition::event(), QMotifStyle::event(), QClipboard::event(), QDnotifySignalThread::event(), QDeclarativeSystemPalette::event(), QDeclarativeWorkerScript::event(), QDeclarativeListModelWorkerAgent::event(), QSystemTrayIcon::event(), QDeclarativePixmapReply::event(), QAbstractAnimation::event(), QDeclarativePixmapReaderThreadObject::event(), QStyleSheetStyle::event(), QCompleter::event(), QFileSystemModel::event(), QDeclarativeXmlQueryThreadObject::event(), QDeclarativeItem::event(), QDeclarativeWorkerScriptEnginePrivate::event(), QCoreApplication::event(), QGraphicsWidget::event(), QAction::event(), QGraphicsScene::event(), QTextControl::event(), QSettings::event(), QXlibScreen::eventDispatcher(), QBBInputContext::eventFilter(), QVistaHelper::eventFilter(), QScriptDebuggerLocalsItemDelegate::eventFilter(), QBBInputContext::filterEvent(), QBBEngine::filterEvent(), QApplicationPrivate::globalEventProcessor(), QDirectFbInput::handleEvents(), QBBInputContext::hasPhysicalKeyboard(), QAbstractItemDelegate::helpEvent(), QSystemTrayIcon::hide(), QmlJSDebugger::AbstractTool::inspector(), QGraphicsScene::invalidate(), QWSServerPrivate::invokeCreate(), QWSServerPrivate::invokeScreenTransform(), QBBInputContext::isComposing(), isProcessBeingDebugged(), QWSInputContext::language(), QCoreApplicationPrivate::notify_helper(), QApplicationPrivate::notify_helper(), QBBInputContext::onCommitText(), QBBInputContext::onDeleteSurroundingText(), QBBInputContext::onFinishComposingText(), QBBInputContext::onSetComposingRegion(), QShortcut::parentWidget(), QXlibScreen::physicalSize(), QKeyMapper::possibleKeys(), QEventDispatcherQPA::processEvents(), QEventDispatcherQWS::processEvents(), QEventDispatcherX11::processEvents(), QXcbConnection::processXcbEvents(), QExceptionNotifier::QExceptionNotifier(), QReadNotifier::QReadNotifier(), qt_x11_incr_event_filter(), QUIKitSoftwareInputHandler::QUIKitSoftwareInputHandler(), QWriteNotifier::QWriteNotifier(), QInotifyFileSystemWatcherEngine::readFromInotify(), QFactoryLoader::refreshAll(), QBBScreenEventThread::run(), QIntMouseListenThread::run(), QEventDispatcherBlackberry::select(), QWSClient::sendConnectedEvent(), QWSClient::sendEmbedEvent(), QWSServerPrivate::sendFontRemovedEvent(), QWSServer::sendIMEvent(), QWSServer::sendIMQuery(), QWSServerPrivate::sendKeyEventUnfiltered(), QWSClient::sendMaxWindowRectEvent(), QWSServerPrivate::sendMouseEventUnfiltered(), QWSClient::sendPropertyNotifyEvent(), QWSClient::sendPropertyReplyEvent(), QWSServerPrivate::sendQCopEvent(), QWSClient::sendRegionEvent(), QWSClient::sendSelectionClearEvent(), QWSClient::sendSelectionRequestEvent(), QBBInputContext::setComposingText(), QMacInputContext::setLastKeydownEvent(), QObjectPrivate::setThreadData_helper(), QBBScreenEventThread::shutdown(), QmlJSDebugger::AbstractViewInspector::slowDownFactor(), QTextControl::toHtml(), QSidebar::urls(), QmlJSDebugger::QDeclarativeViewInspector::viewWidget(), QXlibScreen::waitForClipboardEvent(), and QEventDispatcherBlackberry::wakeUp().

{
    switch (e->type()) {
    case QEvent::Timer:
        timerEvent((QTimerEvent*)e);
        break;

#ifdef QT3_SUPPORT
    case QEvent::ChildInsertedRequest:
        d_func()->sendPendingChildInsertedEvents();
        break;
#endif

    case QEvent::ChildAdded:
    case QEvent::ChildPolished:
#ifdef QT3_SUPPORT
    case QEvent::ChildInserted:
#endif
    case QEvent::ChildRemoved:
        childEvent((QChildEvent*)e);
        break;

    case QEvent::DeferredDelete:
        qDeleteInEventHandler(this);
        break;

    case QEvent::MetaCall:
        {
#ifdef QT_JAMBI_BUILD
            d_func()->inEventHandler = false;
#endif
            QMetaCallEvent *mce = static_cast<QMetaCallEvent*>(e);
            QObjectPrivate::Sender currentSender;
            currentSender.sender = const_cast<QObject*>(mce->sender());
            currentSender.signal = mce->signalId();
            currentSender.ref = 1;
            QObjectPrivate::Sender * const previousSender =
                QObjectPrivate::setCurrentSender(this, &currentSender);
#if defined(QT_NO_EXCEPTIONS)
            mce->placeMetaCall(this);
#else
            QT_TRY {
                mce->placeMetaCall(this);
            } QT_CATCH(...) {
                QObjectPrivate::resetCurrentSender(this, &currentSender, previousSender);
                QT_RETHROW;
            }
#endif
            QObjectPrivate::resetCurrentSender(this, &currentSender, previousSender);
            break;
        }

    case QEvent::ThreadChange: {
        Q_D(QObject);
        QThreadData *threadData = d->threadData;
        QAbstractEventDispatcher *eventDispatcher = threadData->eventDispatcher;
        if (eventDispatcher) {
            QList<QPair<int, int> > timers = eventDispatcher->registeredTimers(this);
            if (!timers.isEmpty()) {
                // set inThreadChangeEvent to true to tell the dispatcher not to release out timer ids
                // back to the pool (since the timer ids are moving to a new thread).
                d->inThreadChangeEvent = true;
                eventDispatcher->unregisterTimers(this);
                d->inThreadChangeEvent = false;
                QMetaObject::invokeMethod(this, "_q_reregisterTimers", Qt::QueuedConnection,
                                          Q_ARG(void*, (new QList<QPair<int, int> >(timers))));
            }
        }
        break;
    }

    default:
        if (e->type() >= QEvent::User) {
            customEvent(e);
            break;
        }
        return false;
    }
    return true;
}

eventFilter()

bool QObject::eventFilter ( QObject *  , QEvent *    )

virtual

Filters events if this object has been installed as an event filter for the watched object.

In your reimplementation of this function, if you want to filter the event out, i.e. stop it being handled further, return true; otherwise return false.

Example:

class MainWindow : public QMainWindow
{
public:
    MainWindow();

protected:
    bool eventFilter(QObject *obj, QEvent *ev);

private:
    QTextEdit *textEdit;
};

MainWindow::MainWindow()
{
    textEdit = new QTextEdit;
    setCentralWidget(textEdit);

    textEdit->installEventFilter(this);
}

bool MainWindow::eventFilter(QObject *obj, QEvent *event)
{
    if (obj == textEdit) {
        if (event->type() == QEvent::KeyPress) {
            QKeyEvent *keyEvent = static_cast<QKeyEvent*>(event);
            qDebug() << "Ate key press" << keyEvent->key();
            return true;
        } else {
            return false;
        }
    } else {
        // pass the event on to the parent class
        return QMainWindow::eventFilter(obj, event);
    }
}

Notice in the example above that unhandled events are passed to the base class's eventFilter() function, since the base class might have reimplemented eventFilter() for its own internal purposes.

Warning

If you delete the receiver object in this function, be sure to return true. Otherwise, Qt will forward the event to the deleted object and the program might crash.

See also

installEventFilter()

Reimplemented in QWorkspaceChild, QWhatsThisPrivate, QAxServerBase, QGtkStyleFilter, QGraphicsScene, QComboBoxPrivateContainer, QScriptBreakpointsItemDelegate, QDragManager, QMacStylePrivate, QScriptDebuggerLocalsItemDelegate, QScriptDebugger, QStateMachine, QCalendarWidget, QMdiArea, QCompleter, QMenuBar, QmlJSDebugger::AbstractViewInspector, QVistaHelper, QTipLabel, QAxHostWidget, QFontDialog, QDialog, QX11EmbedContainer, QAbstractScrollAreaFilter, QMdiSubWindow, QItemDelegate, QMotifStyle, QDeclarativeSystemPalette, QWorkspace, QDeclarativeView, QPlastiqueStyle, QStyledItemDelegate, QWidgetResizeHandler, QWindowsStyle, QDeclarativeLoader, QMeeGoGraphicsSystemSwitchHandler, QScrollArea, QGraphicsProxyWidget, QCalendarTextNavigator, QmlJSDebugger::QDeclarativeViewInspector, QX11EmbedWidget, QAlphaWidget, QBBInputContext, QWidgetAction, QSizeGrip, QDeclarativeApplication, QFocusFrame, QWSEmbedWidget, and QUIKitSoftwareInputHandler.

Definition at line 1375 of file qobject.cpp.

Referenced by QWSEmbedWidget::eventFilter(), QSizeGrip::eventFilter(), QWidgetAction::eventFilter(), QBBInputContext::eventFilter(), QAlphaWidget::eventFilter(), QX11EmbedWidget::eventFilter(), QmlJSDebugger::QDeclarativeViewInspector::eventFilter(), QCalendarTextNavigator::eventFilter(), QGraphicsProxyWidget::eventFilter(), QDeclarativeLoader::eventFilter(), QWindowsStyle::eventFilter(), QDeclarativeView::eventFilter(), QWorkspace::eventFilter(), QDeclarativeSystemPalette::eventFilter(), QMotifStyle::eventFilter(), QMdiSubWindow::eventFilter(), QX11EmbedContainer::eventFilter(), QDialog::eventFilter(), QAxHostWidget::eventFilter(), QVistaHelper::eventFilter(), QmlJSDebugger::AbstractViewInspector::eventFilter(), QCompleter::eventFilter(), QCalendarWidget::eventFilter(), QMdiArea::eventFilter(), QComboBoxPrivateContainer::eventFilter(), QGtkStyleFilter::eventFilter(), QAxServerBase::eventFilter(), QWorkspaceChild::eventFilter(), QGraphicsScene::invalidate(), QCalendarWidget::isNavigationBarVisible(), QVistaHelper::leftMargin(), QApplication::notify(), QCoreApplicationPrivate::sendThroughApplicationEventFilters(), QCoreApplicationPrivate::sendThroughObjectEventFilters(), and QWidgetResizeHandler::setFrameWidth().

{
    return false;
}

findChild()

template<typename T >

T * QObject::findChild ( const QString &  name = QString() ) const

inline

Returns the child of this object that can be cast into type T and that is called name, or 0 if there is no such object.

Omitting the name argument causes all object names to be matched. The search is performed recursively.

If there is more than one child matching the search, the most direct ancestor is returned. If there are several direct ancestors, it is undefined which one will be returned. In that case, findChildren() should be used.

This example returns a child QPushButton of parentWidget named "button1":

QPushButton *button = parentWidget->findChild<QPushButton *>("button1");

This example returns a QListWidget child of parentWidget:

QListWidget *list = parentWidget->findChild<QListWidget *>();

See also

findChildren()

Definition at line 158 of file qobject.h.

Referenced by QDeclarativeVisualDataModelPrivate::data(), QPlastiqueStylePrivate::drawPartialFrame(), QWindowsVistaStyle::drawPrimitive(), embeddedWidget(), QStateMachinePrivate::goToState(), QWorkspacePrivate::maximizeWindow(), menuItemEntry(), QWorkspacePrivate::minimizeWindow(), QWorkspacePrivate::normalizeWindow(), QAxClientSite::OnPosRectChange(), QWindowsVistaStyle::polish(), qFindChild(), QScript::qobjectProtoFuncFindChild(), QPrintDialogPrivate::setupDestination(), QPrintDialogPrivate::setupOptions(), QPrintDialogPrivate::setupPaper(), QPrintDialogPrivate::setupPrinterSettings(), QMdiSubWindow::setWidget(), showNewMessageBox(), QWindowsStyle::styleHint(), QStyleSheetStyle::styleHint(), QMacStyle::unpolish(), and QWindowsVistaStyle::unpolish().

    { return static_cast<T>(qt_qFindChild_helper(this, aName, reinterpret_cast<T>(0)->staticMetaObject)); }

findChildren() [1/2]

template<typename T >

QList< T > QObject::findChildren ( const QString &  name = QString() ) const

inline

Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects.

Omitting the name argument causes all object names to be matched. The search is performed recursively.

The following example shows how to find a list of child QWidget of the specified parentWidget named widgetname:

QList<QWidget *> widgets = parentWidget.findChildren<QWidget *>("widgetname");

This example returns all QPushButtons that are children of parentWidget:

QList<QPushButton *> allPButtons = parentWidget.findChildren<QPushButton *>();

See also

findChild()

Definition at line 162 of file qobject.h.

Referenced by QStateMachinePrivate::applyProperties(), QMetaObject::connectSlotsByName(), QWindowsStyle::eventFilter(), QEventDispatcherMac::flush(), qFindChildren(), QScript::qobjectProtoFuncFindChildren(), QAbstractButtonPrivate::queryButtonList(), QAccessibleApplication::relationTo(), QStyleSheetStyle::repolish(), QWorkspaceChild::setActive(), QWidget::setTabOrder(), and QStateMachinePrivate::unregisterAllTransitions().

    {
        QList<T> list;
        union {
            QList<T> *typedList;
            QList<void *> *voidList;
        } u;
        u.typedList = &list;
        qt_qFindChildren_helper(this, aName, 0, reinterpret_cast<T>(0)->staticMetaObject, u.voidList);
        return list;
    }

findChildren() [2/2]

template<typename T >

QList<T> QObject::findChildren ( const QRegExp &  re ) const

inline

Definition at line 176 of file qobject.h.

    {
        QList<T> list;
        union {
            QList<T> *typedList;
            QList<void *> *voidList;
        } u;
        u.typedList = &list;
        qt_qFindChildren_helper(this, QString(), &re, reinterpret_cast<T>(0)->staticMetaObject, u.voidList);
        return list;
    }

inherits()

bool QObject::inherits ( const char *  className ) const

inline

Returns true if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns false.

A class is considered to inherit itself.

Example:

QTimer *timer = new QTimer;         // QTimer inherits QObject
timer->inherits("QTimer");          // returns true
timer->inherits("QObject");         // returns true
timer->inherits("QAbstractButton"); // returns false

// QVBoxLayout inherits QObject and QLayoutItem
QVBoxLayout *layout = new QVBoxLayout;
layout->inherits("QObject");        // returns true
layout->inherits("QLayoutItem");    // returns true (even though QLayoutItem is not a QObject)

If you need to determine whether an object is an instance of a particular class for the purpose of casting it, consider using qobject_cast<Type *>(object) instead.

See also

metaObject(), qobject_cast()

Definition at line 275 of file qobject.h.

Referenced by QMacStylePrivate::addWidget(), axc_FilterProc(), QX11Data::clipboardWaitForEvent(), QPlastiqueStyle::drawComplexControl(), QCleanlooksStyle::drawComplexControl(), QWindowsXPStyle::drawComplexControl(), QPlastiqueStyle::drawControl(), QWindowsCEStyle::drawPrimitive(), QWindowsMobileStyle::drawPrimitive(), QPlastiqueStyle::drawPrimitive(), QCleanlooksStyle::drawPrimitive(), QWindowsXPStyle::drawPrimitive(), QWindowsStyle::drawPrimitive(), QGtkStyle::drawPrimitive(), QApplication::font(), QToolButton::initStyleOption(), QWindowsXPStylePrivate::isItemViewDelegateLineEdit(), isTreeView(), killTimer(), QAccessibleMdiSubWindow::navigate(), QApplication::palette(), QWindowsXPStyle::pixelMetric(), QPlastiqueStyle::pixelMetric(), QWindowsStyle::pixelMetric(), QMacStyle::pixelMetric(), QWindowsXPStyle::polish(), QWindowsVistaStyle::polish(), QPlastiqueStyle::polish(), QCleanlooksStyle::polish(), qt_aqua_get_known_size(), qt_find_obj_child(), qt_set_x11_resources(), qt_x11_recreateWidget(), QMacStylePrivate::removeWidget(), QWidget::setAttribute(), QStyledItemDelegate::setEditorData(), QItemDelegate::setEditorData(), QWidget::setFocus(), QApplication::setFont(), setObjectName(), QApplicationPrivate::setPalette_helper(), QGraphicsView::setupViewport(), QFocusFrame::setWidget(), QStyleSheetStyle::sizeFromContents(), QCleanlooksStyle::styleHint(), QMacStyle::styleHint(), QCommonStyle::subControlRect(), QWindowsXPStyle::unpolish(), QPlastiqueStyle::unpolish(), QCleanlooksStyle::unpolish(), QAuthDevice::writeData(), and QApplicationPrivate::x11_apply_settings().

        { return const_cast<QObject *>(this)->qt_metacast(classname) != 0; }

installEventFilter()

void QObject::installEventFilter

(

QObject *

filterObj

)

Installs an event filter filterObj on this object.

For example:

monitoredObj->installEventFilter(filterObj);

An event filter is an object that receives all events that are sent to this object. The filter can either stop the event or forward it to this object. The event filter filterObj receives events via its eventFilter() function. The eventFilter() function must return true if the event should be filtered, (i.e. stopped); otherwise it must return false.

If multiple event filters are installed on a single object, the filter that was installed last is activated first.

Here's a KeyPressEater class that eats the key presses of its monitored objects:

class KeyPressEater : public QObject
{
    Q_OBJECT
    ...

protected:
    bool eventFilter(QObject *obj, QEvent *event);
};

bool KeyPressEater::eventFilter(QObject *obj, QEvent *event)
{
    if (event->type() == QEvent::KeyPress) {
        QKeyEvent *keyEvent = static_cast<QKeyEvent *>(event);
        qDebug("Ate key press %d", keyEvent->key());
        return true;
    } else {
        // standard event processing
        return QObject::eventFilter(obj, event);
    }
}

And here's how to install it on two widgets:

KeyPressEater *keyPressEater = new KeyPressEater(this);
QPushButton *pushButton = new QPushButton(this);
QListView *listView = new QListView(this);

pushButton->installEventFilter(keyPressEater);
listView->installEventFilter(keyPressEater);

The QShortcut class, for example, uses this technique to intercept shortcut key presses.

Warning

If you delete the receiver object in your eventFilter() function, be sure to return true. If you return false, Qt sends the event to the deleted object and the program will crash.

Note that the filtering object must be in the same thread as this object. If filterObj is in a different thread, this function does nothing. If either filterObj or this object are moved to a different thread after calling this function, the event filter will not be called until both objects have the same thread affinity again (it is not removed).

See also

removeEventFilter(), eventFilter(), event()

Definition at line 2070 of file qobject.cpp.

Referenced by QDataWidgetMapper::addMapping(), QMeeGoGraphicsSystemSwitchHandler::addWidget(), QMacStylePrivate::addWidget(), QWorkspace::addWindow(), QMdiAreaPrivate::appendChild(), QAbstractItemView::commitData(), QAbstractItemViewPrivate::editor(), QScrollArea::event(), QDataWidgetMapperPrivate::flipEventFilters(), QMenuBarPrivate::handleReparent(), QDeclarativeLoaderPrivate::initResize(), QAxServerBase::internalActivate(), QWindowsStyle::polish(), QMotifStyle::polish(), QPlastiqueStyle::polish(), QBalloonTip::QBalloonTip(), QBBInputContext::QBBInputContext(), QMdiArea::QMdiArea(), QWidgetResizeHandler::QWidgetResizeHandler(), QWorkspaceChild::QWorkspaceChild(), QX11EmbedWidget::QX11EmbedWidget(), QStateMachinePrivate::registerEventTransition(), QWorkspaceChild::setActive(), QScriptDebugger::setCodeWidget(), QMenuBar::setCornerWidget(), QComboBoxPrivateContainer::setItemView(), QCalendarWidgetPrivate::setNavigatorEnabled(), QCompleter::setPopup(), QMdiSubWindowPrivate::setSizeGrip(), QFocusFrame::setWidget(), QScrollArea::setWidget(), QMdiSubWindow::setWidget(), QGraphicsProxyWidgetPrivate::setWidget_helper(), QMdiSubWindowPrivate::showButtonsInMenuBar(), QSizeGripPrivate::updateTopLevelWidget(), and QWSEmbedWidgetPrivate::updateWindow().

{
    Q_D(QObject);
    if (!obj)
        return;
    if (d->threadData != obj->d_func()->threadData) {
        qWarning("QObject::installEventFilter(): Cannot filter events for objects in a different thread.");
        return;
    }

    // clean up unused items in the list
    d->eventFilters.removeAll((QObject*)0);
    d->eventFilters.removeAll(obj);
    d->eventFilters.prepend(obj);
}

isWidgetType()

bool QObject::isWidgetType ( ) const

inline

Returns true if the object is a widget; otherwise returns false.

Calling this function is equivalent to calling inherits("QWidget"), except that it is much faster.

Definition at line 146 of file qobject.h.

Referenced by QGroupBoxPrivate::_q_setChildrenEnabled(), QGroupBox::childEvent(), QSplitter::childEvent(), classIDL(), QScriptEnginePrivate::convertValue(), CompatAccessibleFactory::create(), AccessibleFactory::create(), QPanGestureRecognizer::create(), QWinNativePanGestureRecognizer::create(), QPinchGestureRecognizer::create(), QSwipeGestureRecognizer::create(), QTapGestureRecognizer::create(), QTapAndHoldGestureRecognizer::create(), QGestureManager::deliverEvents(), QWidget::destroy(), do_size_hints(), dumpRecursive(), effectiveState(), QWidget::ensurePolished(), QScrollArea::eventFilter(), QWindowsStyle::eventFilter(), QWhatsThisPrivate::eventFilter(), getNamedAttribute(), QGestureManager::getState(), QWindowsAccessible::GetWindow(), QAccessibleApplication::indexOfChild(), QWidgetPrivate::isBackgroundInherited(), QAxServerBase::isPropertyExposed(), isServerProcess(), killTimer(), make_win_eventUPP(), QCoreApplication::notify(), QApplication::notify(), QApplicationPrivate::notify_helper(), QAction::parentWidget(), parseGeometry(), q_createNativeChildrenAndSetParent(), qSmartSpacing(), qt_grab_cursor(), qt_mac_unregister_widget(), qt_mac_update_widget_position(), qt_set_windows_updateScrollBar(), QMacSwipeGestureRecognizer::recognize(), QMacPinchGestureRecognizer::recognize(), QDeclarativeVME::run(), sendResizeEvents(), QWidget::setLayout(), setObjectName(), QLayout::update(), QAccessible::updateAccessibility(), and QLayout::widgetEvent().

{ return d_ptr->isWidget; }

killTimer()

void QObject::killTimer

(

int

id

)

Kills the timer with timer identifier, id.

The timer identifier is returned by startTimer() when a timer event is started.

See also

timerEvent(), startTimer()

Definition at line 1650 of file qobject.cpp.

Referenced by QUnixSocket::abort(), QStateMachine::cancelDelayedEvent(), QDBusConnectionPrivate::customEvent(), QAxHostWidget::event(), QStateMachine::event(), QPlastiqueStyle::eventFilter(), QMotifStyle::eventFilter(), QTestEventLoop::exitLoop(), findRealWindow(), QAxHostWidget::focusOutEvent(), QFontCache::increaseCost(), QGLBlurTextureCache::insertBlurTextureInfo(), QLineControl::internalInsert(), QMenu::mouseMoveEvent(), QLineControl::processEvent(), QLineControl::processMouseEvent(), qDBusRemoveTimeout(), QTapAndHoldGestureRecognizer::recognize(), QTapAndHoldGestureRecognizer::reset(), QLineControl::resetCursorBlinkTimer(), QMdiSubWindow::resizeEvent(), restartXdndDropExpiryTimer(), QLineControl::setCursorBlinkPeriod(), QTimer::setInterval(), QTimeLine::setPaused(), QMacAnimateCursor::start(), QMacAnimateCursor::stop(), QTimer::stop(), QTimeLine::stop(), QWindowsStylePrivate::stopAnimation(), QBalloonTip::timerEvent(), QMdiSubWindow::timerEvent(), QAbstractSpinBox::timerEvent(), QTableView::timerEvent(), QMdiArea::timerEvent(), QCoreFuriCuri::timerEvent(), QMenu::timerEvent(), QScriptDebugger::timerEvent(), QTreeView::timerEvent(), QPMCache::timerEvent(), QMacStylePrivate::timerEvent(), QFontCache::timerEvent(), QSingleShotTimer::timerEvent(), QGLBlurTextureCache::timerEvent(), QLineControl::timerEvent(), QDeclarativePixmapStore::timerEvent(), QClipboardINCRTransaction::x11Event(), and QSingleShotTimer::~QSingleShotTimer().

{
    Q_D(QObject);
    if (d->threadData->eventDispatcher)
        d->threadData->eventDispatcher->unregisterTimer(id);
}

metaObject()

QMetaObject * QObject::metaObject ( ) const

virtual

Returns a pointer to the meta-object of this object.

A meta-object contains information about a class that inherits QObject, e.g. class name, superclass name, properties, signals and slots. Every QObject subclass that contains the Q_OBJECT macro will have a meta-object.

The meta-object information is required by the signal/slot connection mechanism and the property system. The inherits() function also makes use of the meta-object.

If you have no pointer to an actual object instance but still want to access the meta-object of a class, you can use staticMetaObject .

Example:

QObject *obj = new QPushButton;
obj->metaObject()->className();             // returns "QPushButton"

QPushButton::staticMetaObject.className();  // returns "QPushButton"

See also

staticMetaObject

Reimplemented in QScript::QObjectConnectionManager, QDBusInterface, QSignalEventGenerator, QAxWidget, and QAxObject.

Referenced by QLayout::activate(), QMetaObject::activate(), ActiveObject::ActiveObject(), QAxServerBase::ActiveXProc(), QDBusAdaptorConnector::addAdaptor(), QGraphicsLayoutPrivate::addChildLayoutItem(), QLayout::addChildWidget(), QAccessibleWidget::addControllingSignal(), QGraphicsScene::addItem(), QAxScriptManager::addObject(), QScript::QObjectConnectionManager::addSignalHandler(), QState::addTransition(), QDeclarativeWatcher::addWatch(), QGridLayout::addWidget(), QDeclarativeListReference::append(), QMacStylePrivate::aquaSizeConstrain(), QStyleSheetStyleSelector::attribute(), QDeclarativePropertyPrivate::binding(), QDeclarativeEngineDebugService::buildObjectDump(), QDeclarativeCompiler::buildValueTypeProperty(), QDeclarativeEnginePrivate::cache(), QDeclarativeObjectMethodScriptClass::callOverloaded(), QDeclarativeObjectMethodScriptClass::callPrecise(), QDBusAbstractInterface::callWithArgumentList(), QMetaObject::cast(), check_method_code(), check_parent_thread(), check_signal_macro(), QCoreApplicationPrivate::checkReceiverThread(), checkWidget(), QAxFactory::classID(), QDeclarativeCompiler::compileAlias(), QDeclarativeObjectMethodScriptClass::connect(), QDeclarativePropertyPrivate::connect(), connect(), QMetaObject::connect(), QDeclarativeVMEMetaObject::connectAlias(), QDBusAdaptorConnector::connectAllSignals(), QDeclarativeProperty::connectNotifySignal(), ShaderEffectItem::connectPropertySignals(), QMetaObject::connectSlotsByName(), QDeclarativeContext::contextProperty(), QDeclarativeEnginePrivate::createCache(), QLayoutPrivate::createSpacerItem(), QDeclarativeItemPrivate::data_append(), QDeclarativeMetaType::defaultMethod(), QDeclarativeMetaType::defaultProperty(), QDeclarativeNotifierEndpoint::disconnect(), QDeclarativeObjectMethodScriptClass::disconnect(), disconnect(), QMetaObject::disconnect(), QDBusAdaptorConnector::disconnectAllSignals(), QMetaObject::disconnectOne(), QWindowsStyle::drawPrimitive(), dumpObjectInfo(), dumpRecursive(), QProxyStylePrivate::ensureBaseStyle(), QWidget::ensurePolished(), QApplicationPrivate::enterModal_sys(), err_method_notfound(), QAxFactory::eventsID(), QCoreApplication::exec(), QScript::QtFunction::execute(), QScript::QtPropertyFunction::execute(), QAxFactory::exposeToSuperClass(), QDeclarativePropertyPrivate::findAliasTarget(), QDeclarativeCompiledBindingsPrivate::findproperty(), QDBusConnectionPrivate::findSlot(), QApplication::font(), fromScriptValue(), QScript::QObjectDelegate::getOwnPropertyNames(), QApplicationPrivate::globalEventProcessor(), QStateMachinePrivate::handleTransitionSignal(), QDeclarativeProperty::hasNotifySignal(), QAxFactory::hasStockEvents(), hasValidSignal(), QNetworkReply::ignoreSslErrors(), QDeclarativeBoundSignal::init(), QNetworkReplyImplPrivate::initCacheSaveDevice(), QDeclarativeVisualDataModelDataMetaObject::initialValue(), QDeclarativePropertyPrivate::initProperty(), QAxFactory::interfaceID(), QAxServerBase::internalActivate(), QMetaObject::invokeMethod(), QTest::invokeMethod(), QDeclarativeProperty::isDesignable(), QAxServerBase::isPropertyExposed(), QDeclarativeKeysAttached::keyPressed(), keyTypeForObject(), QStyle::layoutSpacing(), QApplicationPrivate::leaveModal_sys(), make_widget_eventUPP(), QDataWidgetMapper::mappedPropertyName(), QMetaObjectPrivate::memberIndexes(), QDeclarativeProxyMetaObject::metaCall(), QDeclarativeVMEMetaObject::metaCall(), QScript::QtFunction::metaObject(), QDeclarativeProperty::method(), QDeclarativeProperty::name(), QDeclarativePropertyCache::Data::name(), QStyleSheetStyle::nativeFrameWidth(), QDeclarativeEngineDebugService::objectData(), QDeclarativeDebugService::objectToString(), operator<<(), QDeclarativeBindingCompilerPrivate::Result::operator==(), QApplication::palette(), parentWidget(), QStyleSheetStyle::polish(), QDeclarativeValueTypeScriptClass::property(), QDeclarativeObjectMethodScriptClass::property(), QDeclarativeProperty::property(), QDeclarativeObjectScriptClass::property(), QDeclarativePropertyCache::property(), property(), QDeclarativeEngineDebugService::propertyData(), QDeclarativeObjectScriptClass::propertyNames(), QDeclarativeProperty::propertyTypeName(), ptr(), qax_generateDocumentation(), QAxServerBase::QAxServerBase(), qDBusInterfaceInObject(), qDBusIntrospectObject(), qDBusPropertyGet(), QDeclarativeBoundSignalParameters::QDeclarativeBoundSignalParameters(), QDeclarativeOpenMetaObject::QDeclarativeOpenMetaObject(), QDeclarativeVMEMetaObject::QDeclarativeVMEMetaObject(), QTest::qExec(), QTest::qInvokeTestMethods(), QIODevice::QIODevice(), QLayout::QLayout(), qmlExecuteDeferred(), QScript::qobjectProtoFuncToString(), QTest::qPrintDataTags(), QTest::qPrintTestSlots(), QRenderRule::QRenderRule(), QScriptDBusInterfaceConstructor::QScriptDBusInterfaceConstructor(), QScriptDBusMessageConstructor::QScriptDBusMessageConstructor(), QTest::qSignalDumperCallback(), QTest::qSignalDumperCallbackEndSignal(), QTest::qSignalDumperCallbackSlot(), QSignalSpy::QSignalSpy(), qt_adopted_thread_watcher_function(), qt_aqua_get_known_size(), qt_mac_send_modifiers_changed(), QDBusAbstractInterfaceBase::qt_metacall(), qt_nograb(), QTest::qtest_qParseArgs(), QDeclarativeValueTypeScriptClass::queryProperty(), queued_activate(), QVariantToVARIANT(), QDeclarativePropertyPrivate::readValueProperty(), QAxFactory::registerActiveObject(), QStateMachinePrivate::registerSignalTransition(), QDBusAdaptorConnector::relay(), QDBusAdaptorConnector::relaySlot(), QCoreApplicationPrivate::removePostedEvent(), QScript::QObjectConnectionManager::removeSignalHandler(), QGraphicsLayoutPrivate::reparentChildItems(), QDeclarativeEngineDebugService::resetBinding(), QDeclarativeCompiledBindingsPrivate::run(), QScriptEnginePrivate::scriptConnect(), QScriptEnginePrivate::scriptDisconnect(), QKeyMapper::sendKeyEvent(), QDBusAbstractAdaptor::setAutoRelaySignals(), QDeclarativePropertyPrivate::setBinding(), QDeclarativeData::setBindingBit(), QDeclarativePropertyPrivate::setBindingNoEnable(), QNetworkReplyImplPrivate::setCachingEnabled(), QDeclarativeContext::setContextProperty(), QStyledItemDelegate::setEditorData(), QItemDelegate::setEditorData(), QWidget::setFocusProxy(), QGraphicsWidget::setLayout(), QWidget::setLayout(), QStyledItemDelegate::setModelData(), QItemDelegate::setModelData(), QStyleSheetStyle::setProperties(), QDeclarativeValueTypeScriptClass::setProperty(), setProperty(), QDBusPendingCallPrivate::setReplyCallback(), QDeclarativeAbstractAnimation::setRunning(), QNetworkReply::setSslConfiguration(), QDeclarativeBehavior::setTarget(), setupDBusInterface(), QNetworkReply::sslConfiguration(), QThreadPrivate::start(), QmlJSDebugger::AbstractLiveEditTool::titleForItem(), QDeclarativeObjectScriptClass::tostring(), QAxServerBase::UIDeactivate(), QAccessible::updateAccessibility(), QPropertyAnimationPrivate::updateMetaProperty(), QGLContext::updatePaintDevice(), QAxFactory::validateLicenseKey(), QDeclarativeValueTypeFactory::valueType(), VARIANTToQVariant(), QGraphicsView::viewportEvent(), QDeclarativePropertyPrivate::write(), writeProperty(), and QDeclarativeInfo::~QDeclarativeInfo().

moveToThread()

void QObject::moveToThread

(

QThread *

targetThread

)

Changes the thread affinity for this object and its children.

The object cannot be moved if it has a parent. Event processing will continue in the targetThread.

To move an object to the main thread, use QApplication::instance() to retrieve a pointer to the current application, and then use QApplication::thread() to retrieve the thread in which the application lives. For example:

myObject->moveToThread(QApplication::instance()->thread());

If targetThread is zero, all event processing for this object and its children stops.

Note that all active timers for the object will be reset. The timers are first stopped in the current thread and restarted (with the same interval) in the targetThread. As a result, constantly moving an object between threads can postpone timer events indefinitely.

A QEvent::ThreadChange event is sent to this object just before the thread affinity is changed. You can handle this event to perform any special processing. Note that any new events that are posted to this object will be handled in the targetThread.

Warning

This function is not thread-safe; the current thread must be same as the current thread affinity. In other words, this function can only "push" an object from the current thread to another thread, it cannot "pull" an object from any arbitrary thread to the current thread.

See also

thread()

Definition at line 1458 of file qobject.cpp.

Referenced by QDBusConnectionPrivate::checkThread(), connManager(), QAdoptedThread::createThreadForAdoption(), QCoreApplication::init(), QNetworkConfigurationManagerPrivate::initialize(), QGLSignalProxy::instance(), QScriptDebuggerBackendPrivate::postEvent(), QNetworkAccessHttpBackend::postRequest(), QDBusDefaultConnection::QDBusDefaultConnection(), QDeclarativePixmapReader::QDeclarativePixmapReader(), QDeclarativeWorkerScriptEngine::QDeclarativeWorkerScriptEngine(), QDnotifySignalThread::QDnotifySignalThread(), QFactoryLoader::QFactoryLoader(), QFileSystemWatcherEngine::QFileSystemWatcherEngine(), QHostInfoLookupManager::QHostInfoLookupManager(), QInotifyFileSystemWatcherEngine::QInotifyFileSystemWatcherEngine(), QPollingFileSystemWatcherEngine::QPollingFileSystemWatcherEngine(), QWaylandScreen::QWaylandScreen(), QWindowsFileSystemWatcherEngineThread::QWindowsFileSystemWatcherEngineThread(), QDBusConnectionPrivate::sendWithReplyAsync(), and QNetworkConfigurationManagerPrivate::updateConfigurations().

{
    Q_D(QObject);

    if (d->threadData->thread == targetThread) {
        // object is already in this thread
        return;
    }

    if (d->parent != 0) {
        qWarning("QObject::moveToThread: Cannot move objects with a parent");
        return;
    }
    if (d->isWidget) {
        qWarning("QObject::moveToThread: Widgets cannot be moved to a new thread");
        return;
    }

    QThreadData *currentData = QThreadData::current();
    QThreadData *targetData = targetThread ? QThreadData::get2(targetThread) : new QThreadData(0);
    if (d->threadData->thread == 0 && currentData == targetData) {
        // one exception to the rule: we allow moving objects with no thread affinity to the current thread
        currentData = d->threadData;
    } else if (d->threadData != currentData) {
        qWarning("QObject::moveToThread: Current thread (%p) is not the object's thread (%p).\n"
                 "Cannot move to target thread (%p)\n",
                 currentData->thread, d->threadData->thread, targetData->thread);

#ifdef Q_WS_MAC
        qWarning("On Mac OS X, you might be loading two sets of Qt binaries into the same process. "
                 "Check that all plugins are compiled against the right Qt binaries. Export "
                 "DYLD_PRINT_LIBRARIES=1 and check that only one set of binaries are being loaded.");
#endif

        return;
    }

    // prepare to move
    d->moveToThread_helper();

    QOrderedMutexLocker locker(&currentData->postEventList.mutex,
                               &targetData->postEventList.mutex);

    // keep currentData alive (since we've got it locked)
    currentData->ref();

    // move the object
    d_func()->setThreadData_helper(currentData, targetData);

    locker.unlock();

    // now currentData can commit suicide if it wants to
    currentData->deref();
}

objectName()

QString QObject::objectName

(

)

const

Referenced by QLayout::activate(), QLayout::addChildLayout(), QGraphicsLayoutPrivate::addChildLayoutItem(), QLayout::addChildWidget(), QDockAreaLayout::addDockWidget(), QFileSystemWatcher::addPaths(), QGridLayout::addWidget(), QMacStylePrivate::aquaSizeConstrain(), QDeclarativeEngineDebugService::buildObjectList(), checkWidget(), childWidgets(), QGLShaderPrivate::compile(), AccessibleFactory::create(), QLayoutPrivate::createSpacerItem(), DllCanUnloadNow(), dumpObjectInfo(), QAccessibleAbstractScrollArea::elementType(), QApplicationPrivate::enterModal_sys(), QGLEngineSharedShaders::findProgramInCache(), QApplicationPrivate::globalEventProcessor(), QFormLayout::insertRow(), QSplitterPrivate::insertWidget(), QStyleSheetStyle::isNaturalChild(), QApplicationPrivate::leaveModal_sys(), QGLShaderProgram::link(), make_widget_eventUPP(), QDeclarativeEngineDebugService::messageReceived(), QDeclarativeDebugService::objectToString(), operator<<(), QAccessibleItemView::QAccessibleItemView(), QAxHostWidget::QAxHostWidget(), QLayout::QLayout(), QMainWindowLayout::QMainWindowLayout(), QPlaceHolderItem::QPlaceHolderItem(), qt_adopted_thread_watcher_function(), qt_nograb(), QtWndProc(), QDBusAdaptorConnector::relaySlot(), QGraphicsLayoutPrivate::reparentChildItems(), QDockAreaLayout::restoreDockWidget(), QDockAreaLayoutInfo::restoreState(), QToolBarAreaLayout::restoreState(), QToolBarAreaLayout::saveState(), QKeyMapper::sendKeyEvent(), QLCDNumber::setDigitCount(), QStateMachinePrivate::setError(), QWidget::setFocusProxy(), QGraphicsWidget::setLayout(), QWidget::setLayout(), QWSDisplay::setWindowCaption(), QDockAreaLayout::splitDockWidget(), QThreadPrivate::start(), QDockAreaLayout::tabifyDockWidget(), QmlJSDebugger::AbstractLiveEditTool::titleForItem(), QGLContext::updatePaintDevice(), QWSWindowSurface::winId(), QObjectPrivate::Connection::~Connection(), and ~QObject().

parent()

QObject * QObject::parent ( ) const

inline

Returns a pointer to the parent object.

See also

children()

Definition at line 273 of file qobject.h.

Referenced by QColumnViewPrivate::_q_clicked(), QAbstractItemViewPrivate::_q_columnsAboutToBeRemoved(), QLayout::addChildLayout(), QDnotifyFileSystemWatcherEngine::addPaths(), QFileSystemModelPrivate::addVisibleFiles(), QPushButtonPrivate::adjustedMenuPosition(), QWidgetPrivate::adjustFlags(), QLayout::adoptLayout(), QDeclarativeParticleMotionWander::advance(), ancestorOf(), QAbstractTextDocumentLayout::anchorAt(), QDeclarativeGraphicsWidget::anchors(), QDirModelPrivate::appendChild(), QMdiAreaPrivate::appendChild(), QPlainTextEditControl::canInsertFromMimeData(), QTextEditControl::canInsertFromMimeData(), QRubberBand::changeEvent(), QMdiSubWindow::changeEvent(), QNativeSocketEnginePrivate::checkProxy(), QToolBarLayout::checkUsePopupMenu(), QDirModelPrivate::children(), QMenu::clear(), QAbstractItemViewPrivate::clearOrRemove(), QColumnViewPrivate::closeColumns(), QDeclarativeComponentPrivate::complete(), QPanGestureRecognizer::create(), QDeclarativeBinding::createBinding(), QGraphicsScene::createItemGroup(), QPlainTextEditControl::createMimeDataFromSelection(), QTextEditControl::createMimeDataFromSelection(), QUrlModel::dataChanged(), QDeclarativeCompiledBindingsPrivate::Binding::destroy(), QDeclarativeCompiledBindingsPrivate::Binding::disconnect(), QApplicationPrivate::dispatchEnterLeave(), QGraphicsScenePrivate::dispatchHoverEvent(), QTextObject::docHandle(), QTextObject::document(), QTreeView::doItemsLayout(), QTreeView::drawBranches(), QWindowsCEStyle::drawPrimitive(), QWindowsMobileStyle::drawPrimitive(), QMacStyle::drawPrimitive(), QTreeView::drawRow(), QTreeWidget::dropEvent(), QDirModel::dropMimeData(), QListModel::dropMimeData(), QTableModel::dropMimeData(), QScriptEditExtraArea::editor(), QAbstractItemViewPrivate::editor(), QLineControl::emitCursorPositionChanged(), QWinInputContext::enablePopupChild(), QTreeModel::ensureSorted(), QTreeWidgetItemIteratorPrivate::ensureValidIterator(), QRadioButton::event(), QCheckBox::event(), QStatusBar::event(), QMdiSubWindow::event(), QGraphicsScene::event(), QWorkspace::eventFilter(), QMdiSubWindow::eventFilter(), QMenuBar::eventFilter(), QScriptDebuggerLocalsItemDelegate::eventFilter(), QCompletionEngine::filter(), findRealWindow(), QTextHtmlExporter::findUrlForImage(), QSplitterPrivate::findWidget(), QGLWindowSurface::flush(), QGraphicsWidget::focusNextPrevChild(), QDeclarativeItem::forceActiveFocus(), QAbstractTextDocumentLayout::format(), QAbstractTextDocumentLayout::formatIndex(), QGraphicsScenePrivate::gestureEventHandler(), getImage(), getPixmap(), QInputDialog::getText(), QPushButtonPrivate::hitButton(), QTableModel::index(), QDirModel::index(), QSortedModelEngine::indexHint(), QTreeView::indexRowSizeHint(), QCoreApplication::init(), QListModel::insert(), QPlainTextEditControl::insertFromMimeData(), QTextEditControl::insertFromMimeData(), QListModel::insertRows(), QModelIndex::internalId(), QWorkspaceChild::internalRaise(), QLineControl::internalSetText(), isAncestor(), QWidgetPrivate::isBackgroundInherited(), isEmbeddedTabBar(), isStandaloneTabBar(), QStandardItemModel::itemFromIndex(), QAbstractItemView::keyboardSearch(), QDeclarativeKeyNavigationAttached::keyPressed(), QMdiSubWindow::keyPressEvent(), QTreeView::keyPressEvent(), QDeclarativeKeyNavigationAttached::keyReleased(), QTreeViewPrivate::layout(), QGraphicsScenePrivate::leaveScene(), QTextDocumentWithImageResources::loadResource(), QTextControl::loadResource(), QTextDocument::loadResource(), QCompletionEngine::lookupCache(), QAbstractStatePrivate::machine(), QCompletionModel::mapToSource(), QScript::QObjectConnection::mark(), QAbstractItemModel::match(), QCompletionEngine::matchHint(), QScriptDebuggerPrivate::maybeDelete(), QMdiSubWindow::mdiArea(), QListModel::mimeData(), QTableModel::mimeData(), QListModel::mimeTypes(), QTableModel::mimeTypes(), QMdiSubWindow::minimumSizeHint(), QColumnViewGrip::mouseDoubleClickEvent(), QMdiSubWindow::mouseDoubleClickEvent(), QMdiSubWindow::mouseMoveEvent(), QWorkspaceTitleBar::mouseMoveEvent(), QMdiSubWindow::mousePressEvent(), QGroupBox::mouseReleaseEvent(), QMdiSubWindow::mouseReleaseEvent(), QMdiSubWindow::moveEvent(), QColumnViewGrip::moveGrip(), QWidget::nativeParentWidget(), QAccessibleWidget::navigate(), QDeclarativeObjectScriptClass::newQObject(), QTreeWidgetItemIteratorPrivate::next(), QDirModelPrivate::node(), QFileSystemModelPrivate::node(), QDeclarativeEngineDebugService::objectCreated(), QDeclarativeEngineDebugService::objectData(), QWidgetPrivate::paintBackground(), QToolBoxButton::paintEvent(), QMdiSubWindow::paintEvent(), CloseButton::paintEvent(), QTreeModel::parent(), parent(), QAccessibleWidget::parentObject(), QAbstractState::parentState(), QShortcut::parentWidget(), QAction::parentWidget(), QWidget::parentWidget(), QNlaThread::parseBlob(), QNlaThread::parseQuerySet(), QCompleter::pathFromIndex(), QMacStyle::pixelMetric(), QWindowsXPStyle::polish(), QPlastiqueStyle::polish(), QDBusAdaptorConnector::polish(), QToolButtonPrivate::popupTimerDone(), QTreeWidgetItemIteratorPrivate::previous(), QThread::priority(), QAction::QAction(), QBoxLayout::QBoxLayout(), QColorShower::QColorShower(), QComboBox::QComboBox(), QCopChannel::QCopChannel(), qDBusFindAdaptorConnector(), qDBusNewConnection(), QDeclarativeBoundSignalParameters::QDeclarativeBoundSignalParameters(), QDeclarativeDebugClient::QDeclarativeDebugClient(), QDeclarativeKeysAttached::QDeclarativeKeysAttached(), QDeclarativeListModel::QDeclarativeListModel(), QDefaultItemEditorFactory::QDefaultItemEditorFactory(), QDial::QDial(), QDialog::QDialog(), QExceptionNotifier::QExceptionNotifier(), QFrame::QFrame(), QFtp::QFtp(), QGLOverlayWidget::QGLOverlayWidget(), QGridLayout::QGridLayout(), QHttpNetworkConnection::QHttpNetworkConnection(), QLabel::QLabel(), QLineEdit::QLineEdit(), QMainWindow::QMainWindow(), QMenuBar::QMenuBar(), QMessageBoxPrivate::QMessageBoxPrivate(), QAxObject::qObject(), QAxWidget::qObject(), QObject(), QReadNotifier::QReadNotifier(), QScrollBar::QScrollBar(), QSignalMapper::QSignalMapper(), QSizeGrip::QSizeGrip(), QSlider::QSlider(), qSmartSpacing(), QSocketNotifier::QSocketNotifier(), QSound::QSound(), QSpinBox::QSpinBox(), QSplitterHandle::QSplitterHandle(), QSignalEventGenerator::qt_metacall(), QTabWidget::QTabWidget(), QTextBrowser::QTextBrowser(), QTextEdit::QTextEdit(), QTimer::QTimer(), QToolBar::QToolBar(), QToolBarLayout::QToolBarLayout(), QToolButton::QToolButton(), QTranslator::QTranslator(), QTreeModel::QTreeModel(), QTreeWidgetItemIterator::QTreeWidgetItemIterator(), QAbstractButtonPrivate::queryButtonList(), QUnixPrintWidgetPrivate::QUnixPrintWidgetPrivate(), QValidator::QValidator(), QWhatsThis::QWhatsThis(), QWidget::QWidget(), QWorkspace::QWorkspace(), QWriteNotifier::QWriteNotifier(), QWSServer::QWSServer(), QSplitterPrivate::recalc(), QAccessibleWidget::relationTo(), QDBusAdaptorConnector::relay(), QDBusAdaptorConnector::relaySlot(), QDirModel::remove(), QFileSystemModelPrivate::removeNode(), QFileSystemModelPrivate::removeVisibleFile(), QTextDocumentWithImageResources::requestFinished(), QMdiSubWindow::resizeEvent(), QExpandingLineEdit::resizeToContents(), QBBScreen::resizeWindows(), QDirModel::rmdir(), QAbstractItemView::rowsAboutToBeRemoved(), QCompletionEngine::saveInCache(), QTreeView::scrollTo(), QTreeViewPrivate::select(), QColumnView::selectAll(), QItemSelectionModel::selectedColumns(), QItemSelectionModel::selectedRows(), QPrintDialogPrivate::selectPrinter(), QInputContext::sendEvent(), QDBusContextPrivate::set(), QGraphicsScene::setActiveWindow(), QDBusAbstractAdaptor::setAutoRelaySignals(), QPrintPropertiesDialog::setCups(), QStackedLayout::setCurrentIndex(), QFileSystemModel::setData(), QTableModel::setData(), QAction::setFont(), QTableModel::setHorizontalHeaderItem(), QAbstractButton::setIconSize(), QTableModel::setItem(), QTableModel::setItemData(), QWidget::setLayout(), QPageSetupWidget::setRightMargin(), QApplication::setStyle(), QMdiSubWindow::setSystemMenu(), QTableModel::setVerticalHeaderItem(), QGraphicsProxyWidgetPrivate::setWidget_helper(), QMessageBox::setWindowModality(), QMdiSubWindow::showEvent(), QWidget::showFullScreen(), QWidget::showMaximized(), QWidget::showMinimized(), QWidget::showNormal(), QMdiSubWindow::showShaded(), QAbstractItemModel::sibling(), QMacStyle::sizeFromContents(), QStateMachinePrivate::stateEntryLessThan(), QStateMachinePrivate::stateExitLessThan(), QListModel::supportedDropActions(), QTableModel::supportedDropActions(), QTableModel::tableIndex(), QBoxLayout::takeAt(), QFormLayout::takeAt(), QGridLayoutPrivate::takeAt(), QWidget::testAttribute(), QPlastiqueStyle::unpolish(), QLayout::update(), QDeclarativeCompiledBindingsPrivate::Binding::update(), QAbstractItemViewPrivate::updateEditorData(), QMenuBarPrivate::updateGeometries(), QWidgetPrivate::updateGeometry_helper(), QDeclarativeGradientStop::updateGradient(), QStyleSheetStyle::updateStyleSheetFont(), QTreeModel::view(), QMdiArea::viewportEvent(), QHeaderViewPrivate::viewSectionSizeHint(), QListView::visualRegionForSelection(), QTreeView::visualRegionForSelection(), QAxScriptSite::window(), QX11EmbedWidgetPrivate::xEmbedWidget(), ObjectData::~ObjectData(), QApplication::~QApplication(), QComboBoxPrivate::~QComboBoxPrivate(), QDeclarativeConnections::~QDeclarativeConnections(), QDeclarativePackageAttached::~QDeclarativePackageAttached(), QScript::QObjectDelegate::~QObjectDelegate(), QObjectPrivate::~QObjectPrivate(), and QPPDOptionsEditor::~QPPDOptionsEditor().

{ return d_ptr->parent; }

property()

QVariant QObject::property

(

const char *

name

)

const

Returns the value of the object's name property.

If no such property exists, the returned variant is invalid.

Information about all available properties is provided through the metaObject() and dynamicPropertyNames().

See also

setProperty(), QVariant::isValid(), metaObject(), dynamicPropertyNames()

Definition at line 3807 of file qobject.cpp.

Referenced by QNetworkManagerInterfaceDeviceWireless::activeAccessPoint(), QNetworkManagerInterface::activeConnections(), QSocks5SocketEngine::bind(), QNetworkManagerInterfaceDeviceWireless::bitrate(), QNetworkManagerInterfaceDeviceWired::carrier(), ShaderEffectItem::changeSource(), QX11Data::clipboardWaitForEvent(), QDataWidgetMapperPrivate::commit(), QDeclarativeCompiledBindings::configBinding(), QNetworkManagerConnectionActive::connection(), QFtpDTP::connectToHost(), QFtpPI::connectToHost(), QDeclarativeContext::contextProperty(), QAccessibleAbstractSpinBox::currentValue(), QNetworkManagerConnectionActive::defaultRoute(), QDeclarativeAction::deleteFromBinding(), QNetworkManagerConnectionActive::devices(), QNetworkManagerInterfaceDevice::deviceType(), QNetworkManagerIp4Config::domains(), QWindowsVistaStyle::drawComplexControl(), QWindowsVistaStyle::drawControl(), QWindowsVistaStyle::drawPrimitive(), QWizard::field(), QDeclarativeCompiledBindingsPrivate::findproperty(), QNetworkManagerInterfaceAccessPoint::flags(), QNetworkManagerInterfaceAccessPoint::frequency(), QXlibClipboard::getDataInFormat(), QOfonoManagerInterface::getProperty(), QConnmanManagerInterface::getProperty(), QOfonoModemInterface::getProperty(), QOfonoNetworkRegistrationInterface::getProperty(), QOfonoNetworkOperatorInterface::getProperty(), QOfonoSimInterface::getProperty(), QOfonoDataConnectionManagerInterface::getProperty(), QOfonoPrimaryDataContextInterface::getProperty(), QOfonoSmsInterface::getProperty(), QApplicationPrivate::globalEventProcessor(), QNetworkManagerInterfaceAccessPoint::hwAddress(), QNetworkManagerInterfaceDeviceWired::hwAddress(), QNetworkManagerInterfaceDeviceWireless::hwAddress(), QWizardPrivate::init(), QHttpSocketEngine::initialize(), QDeclarativeVisualDataModelDataMetaObject::initialValue(), QDBusAbstractInterface::internalPropGet(), QAxServerBase::Invoke(), QNetworkManagerInterfaceDevice::ip4Address(), QNetworkManagerInterfaceDevice::ip4config(), QWizardPage::isComplete(), QAxServerBase::isPropertyExposed(), QInputDialogSpinBox::keyPressEvent(), QInputDialogDoubleSpinBox::keyPressEvent(), QTcpServer::listen(), QAxServerBase::Load(), QHostInfo::lookupHost(), QNetworkManagerInterfaceAccessPoint::maxBitrate(), QAccessibleAbstractSpinBox::maximumValue(), QDeclarativeEngineDebugService::messageReceived(), QJSDebugService::messageReceived(), QAccessibleAbstractSpinBox::minimumValue(), QNetworkManagerInterfaceAccessPoint::mode(), QNetworkManagerInterfaceDeviceWireless::mode(), QNetworkManagerInterfaceDevice::networkInterface(), QAxEventSink::OnChanged(), QNetworkAccessFtpBackend::open(), parentWidget(), QNetworkAccessHttpBackend::postRequest(), QTextControlPrivate::rectForPosition(), QStateMachinePrivate::registerRestorable(), QTextEditPrivate::relayoutDocument(), QDeclarativeEngineDebugService::resetBinding(), QTextEdit::resizeEvent(), QNetworkManagerInterfaceAccessPoint::rsnFlags(), QAxServerBase::Save(), send_targets_selection(), QWSServer::sendIMQuery(), QWSClient::sendPropertyNotifyEvent(), QWSClient::sendPropertyReplyEvent(), QNetworkManagerConnectionActive::serviceName(), QDeclarativeEngineDebugService::setBinding(), QStyledItemDelegate::setEditorData(), QItemDelegate::setEditorData(), QDeclarativeKeyNavigationAttached::setFocusNavigation(), QStyleSheetStyle::setGeometry(), QStyledItemDelegate::setModelData(), QItemDelegate::setModelData(), QStyleSheetStyle::setPalette(), QStyleSheetStyle::setProperties(), QTcpServer::setSocketDescriptor(), QAbstractSocket::setSocketDescriptor(), QDeclarativeBehavior::setTarget(), QFtpDTP::setupListener(), QHttpSocketEngine::slotSocketConnected(), QNetworkManagerConnectionActive::specificObject(), QNetworkManagerInterfaceDeviceWired::speed(), QNetworkManagerInterfaceAccessPoint::ssid(), QNetworkManagerInterface::state(), QNetworkManagerInterfaceDevice::state(), QNetworkManagerConnectionActive::state(), QNetworkManagerInterfaceAccessPoint::strength(), QDeclarativeVisualDataModel::stringValue(), QMacStylePrivate::timerEvent(), QNetworkManagerInterfaceDevice::udi(), QStyleSheetStyle::unsetPalette(), ShaderEffectItem::updateEffectState(), QDeclarativeQtScriptExpression::updateGuards(), ShaderEffectItem::updateProperties(), QWizardHeader::vistaDisabled(), QAbstractSocket::waitForConnected(), QNetworkManagerInterfaceDeviceWireless::wirelessCapabilities(), QNetworkManagerInterface::wirelessEnabled(), QNetworkManagerInterface::wirelessHardwareEnabled(), and QNetworkManagerInterfaceAccessPoint::wpaFlags().

{
    Q_D(const QObject);
    const QMetaObject* meta = metaObject();
    if (!name || !meta)
        return QVariant();

    int id = meta->indexOfProperty(name);
    if (id < 0) {
        if (!d->extraData)
            return QVariant();
        const int i = d->extraData->propertyNames.indexOf(name);
        return d->extraData->propertyValues.value(i);
    }
    QMetaProperty p = meta->property(id);
#ifndef QT_NO_DEBUG
    if (!p.isReadable())
        qWarning("%s::property: Property \"%s\" invalid or does not exist",
                 metaObject()->className(), name);
#endif
    return p.read(this);
}

receivers()

int QObject::receivers ( const char *  signal ) const

protected

Returns the number of receivers connected to the signal.

Since both slots and signals can be used as receivers for signals, and the same connections can be made many times, the number of receivers is the same as the number of connections made from this signal.

When calling this function, you can use the SIGNAL() macro to pass a specific signal:

if (receivers(SIGNAL(valueChanged(QByteArray))) > 0) {
    QByteArray data;
    get_the_value(&data);       // expensive operation
    emit valueChanged(data);
}

As the code snippet above illustrates, you can use this function to avoid emitting a signal that nobody listens to.

Warning

This function violates the object-oriented principle of modularity. However, it might be useful when you need to perform expensive initialization only if something is connected to a signal.

Definition at line 2406 of file qobject.cpp.

Referenced by QToolButtonPrivate::popupTimerDone(), and qt_mac_watchingAboutToShow().

{
    Q_D(const QObject);
    int receivers = 0;
    if (signal) {
        QByteArray signal_name = QMetaObject::normalizedSignature(signal);
        signal = signal_name;
#ifndef QT_NO_DEBUG
        if (!check_signal_macro(this, signal, "receivers", "bind"))
            return 0;
#endif
        signal++; // skip code
        int signal_index = d->signalIndex(signal);
        if (signal_index < 0) {
#ifndef QT_NO_DEBUG
            err_method_notfound(this, signal-1, "receivers");
#endif
            return false;
        }

        Q_D(const QObject);
        QMutexLocker locker(signalSlotLock(this));
        if (d->connectionLists) {
            if (signal_index < d->connectionLists->count()) {
                const QObjectPrivate::Connection *c =
                    d->connectionLists->at(signal_index).first;
                while (c) {
                    receivers += c->receiver ? 1 : 0;
                    c = c->nextConnectionList;
                }
            }
        }
    }
    return receivers;
}

registerUserData()

uint QObject::registerUserData ( )

static

Warning

This function is not part of the public interface.

Definition at line 3989 of file qobject.cpp.

{
    static int user_data_registration = 0;
    return user_data_registration++;
}

removeEventFilter()

void QObject::removeEventFilter

(

QObject *

obj

)

Removes an event filter object obj from this object.

The request is ignored if such an event filter has not been installed.

All event filters for this object are automatically removed when this object is destroyed.

It is always safe to remove an event filter, even during event filter activation (i.e. from the eventFilter() function).

See also

installEventFilter(), eventFilter(), event()

Definition at line 2099 of file qobject.cpp.

Referenced by QDataWidgetMapper::clearMapping(), QAbstractItemView::closeEditor(), QAbstractItemView::commitData(), QMdiAreaPrivate::disconnectSubWindow(), QScrollArea::event(), QDataWidgetMapperPrivate::flipEventFilters(), QMenuBarPrivate::handleReparent(), QAbstractItemViewPrivate::releaseEditor(), QMdiSubWindowPrivate::removeBaseWidget(), QMdiSubWindowPrivate::removeButtonsFromMenuBar(), QDataWidgetMapper::removeMapping(), QWorkspaceChild::setActive(), QComboBoxPrivateContainer::setItemView(), QCalendarWidgetPrivate::setNavigatorEnabled(), QFocusFrame::setWidget(), QGraphicsProxyWidgetPrivate::setWidget_helper(), QAxServerBase::UIDeactivate(), QWindowsStyle::unpolish(), QMotifStyle::unpolish(), QPlastiqueStyle::unpolish(), QSizeGripPrivate::updateTopLevelWidget(), QWSEmbedWidgetPrivate::updateWindow(), and QBBInputContext::~QBBInputContext().

{
    Q_D(QObject);
    for (int i = 0; i < d->eventFilters.count(); ++i) {
        if (d->eventFilters.at(i) == obj)
            d->eventFilters[i] = 0;
    }
}

sender()

QObject * QObject::sender ( ) const

protected

Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns 0.

The pointer is valid only during the execution of the slot that calls this function from this object's thread context.

The pointer returned by this function becomes invalid if the sender is destroyed, or if the slot is disconnected from the sender's signal.

Warning

This function violates the object-oriented principle of modularity. However, getting access to the sender might be useful when many signals are connected to a single slot.

As mentioned above, the return value of this function is not valid when the slot is called via a Qt::DirectConnection from a thread different from this object's thread. Do not use this function in this type of scenario.

See also

senderSignalIndex(), QSignalMapper

Definition at line 2327 of file qobject.cpp.

Referenced by QApplicationPrivate::_q_alertTimeOut(), QWSServerPrivate::_q_clientClosed(), QTabBarPrivate::_q_closeTab(), QWSServerPrivate::_q_doClient(), QWizardPrivate::_q_emitCustomButtonClicked(), QColumnViewPrivate::_q_gripMoved(), QDialogButtonBoxPrivate::_q_handleButtonDestroyed(), QTabBarPrivate::_q_scrollTabs(), QMetaObject::activate(), QScript::QObjectConnectionManager::addSignalHandler(), QWidgetAnimator::animationFinished(), QmlJSDebugger::QmlToolBar::changeAnimationSpeed(), QMetaObjectPrivate::connect(), connect(), QmlJSDebugger::LiveSelectionTool::contextMenuElementSelected(), QMetaObjectPrivate::disconnect(), disconnect(), QVGFontEngineCleaner::fontEngineDestroyed(), QSignalMapper::map(), QUnicodeControlCharacterMenu::menuActionTriggered(), QDeclarativeDataLoader::networkReplyFinished(), QDeclarativeDataLoader::networkReplyProgress(), QDeclarativePixmapReaderThreadObject::networkRequestDone(), QNetworkManagerEngine::newConnection(), QSignalTransition::QSignalTransition(), QSignalEventGenerator::qt_metacall(), QAxServerBase::qt_metacall(), QNetworkManagerEngine::removeConnection(), QScript::QObjectConnectionManager::removeSignalHandler(), QAxScriptManager::scriptError(), QSoftKeyManager::sendKeyEvent(), QSignalTransition::setSenderObject(), QGLShaderProgram::shaderDestroyed(), QMainWindowLayout::tabChanged(), QNetworkManagerEngine::updateAccessPoint(), QNetworkConfigurationManagerPrivate::updateConfigurations(), QNetworkManagerEngine::updateConnection(), QScriptBreakpointsItemDelegate::validateInput(), and ~QObject().

{
    Q_D(const QObject);

    QMutexLocker locker(signalSlotLock(this));
    if (!d->currentSender)
        return 0;

    for (QObjectPrivate::Connection *c = d->senders; c; c = c->next) {
        if (c->sender == d->currentSender->sender)
            return d->currentSender->sender;
    }

    return 0;
}

senderSignalIndex()

int QObject::senderSignalIndex ( ) const

protected

Since

4.8

Returns the meta-method index of the signal that called the currently executing slot, which is a member of the class returned by sender(). If called outside of a slot activated by a signal, -1 is returned.

For signals with default parameters, this function will always return the index with all parameters, regardless of which was used with connect(). For example, the signal {destroyed(QObject *obj = 0)} will have two different indexes (with and without the parameter), but this function will always return the index with a parameter. This does not apply when overloading signals with different parameters.

Warning

This function violates the object-oriented principle of modularity. However, getting access to the signal index might be useful when many signals are connected to a single slot.

The return value of this function is not valid when the slot is called via a Qt::DirectConnection from a thread different from this object's thread. Do not use this function in this type of scenario.

See also

sender(), QMetaObject::indexOfSignal(), QMetaObject::method()

Definition at line 2368 of file qobject.cpp.

{
    Q_D(const QObject);

    QMutexLocker locker(signalSlotLock(this));
    if (!d->currentSender)
        return -1;

    for (QObjectPrivate::Connection *c = d->senders; c; c = c->next) {
        if (c->sender == d->currentSender->sender)
            return d->currentSender->signal;
    }

    return -1;
}

setObjectName()

void QObject::setObjectName

(

const QString &

name

)

Definition at line 1112 of file qobject.cpp.

Referenced by QWorkspace::addWindow(), QX11Data::clipboardReadIncrementalProperty(), QFtpDTP::connectToHost(), QFileDialogPrivate::createMenuActions(), QCalendarWidgetPrivate::createNavigationBar(), QLineEdit::createStandardContextMenu(), QScriptDebugger::createStandardToolBar(), QFileDialogPrivate::createWidgets(), QWizardPrivate::ensureButton(), QMdiSubWindowPrivate::enterRubberBandMode(), QRadioButton::event(), QCheckBox::event(), QGLEngineSharedShaders::findProgramInCache(), QSplitterPrivate::findWidget(), QMainWindowLayout::getSeparatorWidget(), QGestureManager::getState(), QMdiAreaPrivate::highlightNextSubWindow(), QPushButtonPrivate::hitButton(), QWorkspaceChild::iconWidget(), QDockWidgetPrivate::init(), QAbstractSpinBoxPrivate::init(), QMessageBoxPrivate::init(), QTabWidgetPrivate::init(), QDateTimeEditPrivate::initCalendarPopup(), QToolBox::insertItem(), QSplitterPrivate::insertWidget(), QGroupBox::mouseReleaseEvent(), QPageSetupDialogPrivate::openCarbonPageLayout(), QPrintDialogPrivate::openCarbonPrintPanel(), QToolBoxButton::paintEvent(), QAuBucketQWS::QAuBucketQWS(), QAuServerNAS::QAuServerNAS(), QAuServerQWS::QAuServerQWS(), qax_create_object_wrapper(), QAxHostWidget::QAxHostWidget(), QAxScriptEngine::QAxScriptEngine(), QBoxLayout::QBoxLayout(), QCleanlooksStyle::QCleanlooksStyle(), QComboBox::QComboBox(), QCopChannel::QCopChannel(), QDesktopWidget::QDesktopWidget(), QDial::QDial(), QDialog::QDialog(), QDoubleValidator::QDoubleValidator(), QFrame::QFrame(), QFtp::QFtp(), QFtpDTP::QFtpDTP(), QFtpPI::QFtpPI(), QGridLayout::QGridLayout(), QHBoxLayout::QHBoxLayout(), QIntValidator::QIntValidator(), QLabel::QLabel(), QLineEdit::QLineEdit(), QLinuxInputKeyboardHandler::QLinuxInputKeyboardHandler(), QLinuxInputMouseHandler::QLinuxInputMouseHandler(), QMainWindow::QMainWindow(), QMainWindowLayout::QMainWindowLayout(), QMDIControl::QMDIControl(), QMenuBar::QMenuBar(), QMenuBarExtension::QMenuBarExtension(), QObject(), QPlastiqueStyle::QPlastiqueStyle(), QRegExpValidator::QRegExpValidator(), QScrollBar::QScrollBar(), QSessionManager::QSessionManager(), QSignalMapper::QSignalMapper(), QSizeGrip::QSizeGrip(), QSlider::QSlider(), QSocketNotifier::QSocketNotifier(), QSound::QSound(), QSpinBox::QSpinBox(), QSpinBoxValidator::QSpinBoxValidator(), qt_tablet_init(), qt_tablet_init_wce(), QTabWidget::QTabWidget(), QTextBrowser::QTextBrowser(), QTextEdit::QTextEdit(), QTimer::QTimer(), QToolBar::QToolBar(), QToolBarExtension::QToolBarExtension(), QToolButton::QToolButton(), QTranslator::QTranslator(), QTsLibMouseHandler::QTsLibMouseHandler(), QValidator::QValidator(), QVBoxLayout::QVBoxLayout(), QVNCIntegration::QVNCIntegration(), QWidget::QWidget(), QWorkspace::QWorkspace(), QWSLinuxInputKbPrivate::QWSLinuxInputKbPrivate(), QWSLinuxInputMousePrivate::QWSLinuxInputMousePrivate(), QWSServer::QWSServer(), QWSTtyKbPrivate::QWSTtyKbPrivate(), QAction::setFont(), QAbstractButton::setIconSize(), QMessageBox::setInformativeText(), setupOwner(), QFtpDTP::setupSocket(), QMessageBox::setWindowModality(), QWorkspacePrivate::showMaximizeControls(), QToolTip::showText(), QScriptEngineDebugger::standardWindow(), and QThreadPoolPrivate::startThread().

{
    Q_D(QObject);
    bool objectNameChanged = d->declarativeData && d->objectName != name;

    d->objectName = name;

    if (objectNameChanged)
        d->declarativeData->objectNameChanged(d->declarativeData, this);
}

setParent()

void QObject::setParent

(

QObject *

parent

)

Makes the object a child of parent.

See also

QWidget::setParent()

Definition at line 1950 of file qobject.cpp.

Referenced by QLocalServerPrivate::_q_onNewConnection(), QToolBar::actionEvent(), QLayout::addChildLayout(), QStateMachine::addState(), QState::addTransition(), QDeclarativeWatcher::addWatch(), QDeclarativeComponentPrivate::createObject(), QGraphicsProxyWidget::createProxyForChildWidget(), QDeclarativeEnginePrivate::createQmlObject(), QNetworkAccessManager::createRequest(), QLayoutPrivate::createSpacerItem(), QNetworkDiskCache::data(), QDeclarativeItemPrivate::data_append(), QDeclarativeFlickablePrivate::data_append(), QDeclarativeFlickablePrivate::data_clear(), effectiveState(), QProxyStylePrivate::ensureBaseStyle(), QGestureManager::getState(), inherits(), QLineEditPrivate::init(), QDeclarativeVisualDataModelPartsMetaObject::initialValue(), QAnimationGroup::insertAnimation(), QNetworkReplyImplPrivate::migrateBackend(), QNetworkAccessFtpBackend::open(), QNetworkAccessManager::post(), QNetworkAccessHttpBackend::postRequest(), QNetworkAccessManager::put(), QAbstractAnimation::QAbstractAnimation(), QDeclarativeBinding::QDeclarativeBinding(), QHBoxLayout::QHBoxLayout(), QLayout::QLayout(), QMainWindowLayout::QMainWindowLayout(), QObject(), QProxyStyle::QProxyStyle(), QStateMachine::QStateMachine(), QVBoxLayout::QVBoxLayout(), QWizardPrivate::recreateLayout(), QStateMachine::removeState(), QState::removeTransition(), QDeclarativeItemPrivate::resources_append(), QDeclarativeItemPrivate::resources_clear(), QNetworkAccessCacheBackend::sendCacheContents(), QNetworkAccessHttpBackend::sendCacheContents(), QDeclarativeAbstractAnimation::setGroup(), QApplication::setInputContext(), QWidget::setLayout(), QDeclarativeGraphics_DerivedObject::setParent_noEvent(), QFileDialog::setProxyModel(), QApplication::setStyle(), QApplication::setStyleSheet(), QHttpThreadDelegate::startRequest(), QApplication::style(), QAnimationGroup::takeAnimation(), QBoxLayout::takeAt(), QFormLayout::takeAt(), QGridLayoutPrivate::takeAt(), QWidget::takeLayout(), QCoreFuriCuri::timerEvent(), QDeclarativePackage::~QDeclarativePackage(), and QSingleDesktopWidget::~QSingleDesktopWidget().

{
    Q_D(QObject);
    Q_ASSERT(!d->isWidget);
    d->setParent_helper(parent);
}

setProperty()

bool QObject::setProperty	(	const char *	name,
		const QVariant &	value
	)

Sets the value of the object's name property to value.

If the property is defined in the class using ) and;.

Dynamic properties can be queried again using property() and can be removed by setting the property value to an invalid QVariant. Changing the value of a dynamic property causes a QDynamicPropertyChangeEvent to be sent to the object.

Note: Dynamic properties starting with "_q_" are reserved for internal purposes.

See also

property(), metaObject(), dynamicPropertyNames()

Definition at line 3755 of file qobject.cpp.

Referenced by QStateMachinePrivate::_q_animationFinished(), QStateMachinePrivate::applyProperties(), QSocks5SocketEngine::bind(), QWizardPage::cleanupPage(), QStyleSheetStyle::clearWidgetFont(), QFtpDTP::connectToHost(), QFtpPI::connectToHost(), QWSDisplay::convertSelection(), QSslSocketPrivate::createPlainSocket(), QDirectFBWindowSurface::createWindow(), QWindowsVistaStyle::drawComplexControl(), QWindowsVistaStyle::drawControl(), QWindowsVistaStyle::drawPrimitive(), QHttpNetworkConnectionChannel::ensureConnection(), QHttpNetworkConnectionChannel::init(), QSocks5SocketEnginePrivate::initialize(), QAbstractSocketPrivate::initSocketLayer(), QDBusAbstractInterface::internalPropSet(), QInputDialogSpinBox::keyPressEvent(), QInputDialogDoubleSpinBox::keyPressEvent(), QScriptEngine::newFunction(), QNetworkAccessFtpBackend::open(), QTipLabel::placeTip(), QDataWidgetMapperPrivate::populate(), QStyleSheetStyle::saveWidgetFont(), QAccessibleAbstractSpinBox::setCurrentValue(), QStyledItemDelegate::setEditorData(), QItemDelegate::setEditorData(), QWizard::setField(), QDirectFBWindowSurface::setGeometry(), QStyleSheetStyle::setGeometry(), QStyleSheetStyle::setProperties(), QFtpDTP::setupListener(), QNetworkAccessBackend::start(), QTipLabel::styleSheetParentDestroyed(), QStyleSheetStyle::unpolish(), and QPropertyAnimationPrivate::updateProperty().

{
    Q_D(QObject);
    const QMetaObject* meta = metaObject();
    if (!name || !meta)
        return false;

    int id = meta->indexOfProperty(name);
    if (id < 0) {
        if (!d->extraData)
            d->extraData = new QObjectPrivate::ExtraData;

        const int idx = d->extraData->propertyNames.indexOf(name);

        if (!value.isValid()) {
            if (idx == -1)
                return false;
            d->extraData->propertyNames.removeAt(idx);
            d->extraData->propertyValues.removeAt(idx);
        } else {
            if (idx == -1) {
                d->extraData->propertyNames.append(name);
                d->extraData->propertyValues.append(value);
            } else {
                d->extraData->propertyValues[idx] = value;
            }
        }

        QDynamicPropertyChangeEvent ev(name);
        QCoreApplication::sendEvent(this, &ev);

        return false;
    }
    QMetaProperty p = meta->property(id);
#ifndef QT_NO_DEBUG
    if (!p.isWritable())
        qWarning("%s::setProperty: Property \"%s\" invalid,"
                 " read-only or does not exist", metaObject()->className(), name);
#endif
    return p.write(this, value);
}

setUserData()

void QObject::setUserData	(	uint	id,
		QObjectUserData *	data
	)

Warning

This function is not part of the public interface.

Definition at line 4003 of file qobject.cpp.

Referenced by QTextBlock::operator<().

{
    Q_D(QObject);
    if (!d->extraData)
        d->extraData = new QObjectPrivate::ExtraData;

    if (d->extraData->userData.size() <= (int) id)
        d->extraData->userData.resize((int) id + 1);
    d->extraData->userData[id] = data;
}

signalsBlocked()

bool QObject::signalsBlocked ( ) const

inline

Returns true if signals are blocked; otherwise returns false.

Signals are not blocked by default.

See also

blockSignals()

Definition at line 148 of file qobject.h.

Referenced by QTreeModel::emitDataChanged(), QAxEventSink::Invoke(), QAxEventSink::OnChanged(), QTreeModel::removeRows(), QColSpinBox::setValue(), and QBuffer::writeData().

{ return d_ptr->blockSig; }

startTimer()

int QObject::startTimer

(

int

interval

)

Starts a timer and returns a timer identifier, or returns zero if it could not start a timer.

A timer event will occur every interval milliseconds until killTimer() is called. If interval is 0, then the timer event occurs once every time there are no more window system events to process.

The virtual timerEvent() function is called with the QTimerEvent event parameter class when a timer event occurs. Reimplement this function to get timer events.

If multiple timers are running, the QTimerEvent::timerId() can be used to find out which timer was activated.

Example:

class MyObject : public QObject
{
    Q_OBJECT

public:
    MyObject(QObject *parent = 0);

protected:
    void timerEvent(QTimerEvent *event);
};

MyObject::MyObject(QObject *parent)
    : QObject(parent)
{
    startTimer(50);     // 50-millisecond timer
    startTimer(1000);   // 1-second timer
    startTimer(60000);  // 1-minute timer
}

void MyObject::timerEvent(QTimerEvent *event)
{
    qDebug() << "Timer ID:" << event->timerId();
}

Note that QTimer's accuracy depends on the underlying operating system and hardware. Most platforms support an accuracy of 20 milliseconds; some provide more. If Qt is unable to deliver the requested number of timer events, it will silently discard some.

The QTimer class provides a high-level programming interface with single-shot timers and timer signals instead of events. There is also a QBasicTimer class that is more lightweight than QTimer and less clumsy than using timer IDs directly.

See also

timerEvent(), killTimer(), QTimer::singleShot()

Definition at line 1623 of file qobject.cpp.

Referenced by QBalloonTip::balloon(), QUnixSocket::close(), QTableView::columnResized(), QTreeView::columnResized(), QX11Data::dndEnable(), QComboBoxPrivateScroller::enterEvent(), QTestEventLoop::enterLoop(), QPlastiqueStyle::eventFilter(), QMotifStyle::eventFilter(), QAxHostWidget::focusInEvent(), QClipboardWatcher::getDataInFormat(), QFontCache::increaseCost(), QPMCache::insert(), QGLBlurTextureCache::insertBlurTextureInfo(), QLineControl::internalInsert(), QMenu::mouseMoveEvent(), QStateMachine::postDelayedEvent(), QLineControl::processKeyEvent(), QLineControl::processMouseEvent(), QClipboardINCRTransaction::QClipboardINCRTransaction(), QCoreFuriCuri::QCoreFuriCuri(), qDBusRealAddTimeout(), QSingleShotTimer::QSingleShotTimer(), qt_check_clipboard_sentinel(), qt_check_selection_sentinel(), QTapAndHoldGestureRecognizer::recognize(), QPMCache::replace(), QLineControl::resetCursorBlinkTimer(), QMdiSubWindow::resizeEvent(), restartXdndDropExpiryTimer(), QTimeLine::resume(), QTableView::rowResized(), QLineControl::setCursorBlinkPeriod(), QTimer::setInterval(), QTimeLine::setPaused(), QBasicTimer::start(), QMacAnimateCursor::start(), QTimer::start(), QTimeLine::start(), QWindowsStylePrivate::startAnimation(), QMacStylePrivate::startAnimationTimer(), QAbstractSpinBox::timerEvent(), QCoreFuriCuri::timerEvent(), QPMCache::timerEvent(), QFontCache::timerEvent(), QDeclarativePixmapStore::unreferencePixmap(), and QClipboardINCRTransaction::x11Event().

{
    Q_D(QObject);

    if (interval < 0) {
        qWarning("QObject::startTimer: QTimer cannot have a negative interval");
        return 0;
    }

    d->pendTimer = true;                                // set timer flag

    if (!d->threadData->eventDispatcher) {
        qWarning("QObject::startTimer: QTimer can only be used with threads started with QThread");
        return 0;
    }
    return d->threadData->eventDispatcher->registerTimer(interval, this);
}

thread()

QThread * QObject::thread

(

)

const

Returns the thread in which the object lives.

See also

moveToThread()

Definition at line 1419 of file qobject.cpp.

Referenced by QDBusConnectionPrivate::activateCall(), QEventDispatcherUNIX::activateTimers(), QWindowsFileSystemWatcherEngine::addPaths(), QDBusAbstractInterface::callWithArgumentList(), QCoreApplicationPrivate::checkReceiverThread(), QDBusConnectionPrivate::checkThread(), QNetworkConfigurationManagerPrivate::cleanup(), QDBusConnectionPrivate::deleteYourself(), QDBusConnectionPrivate::deliverCall(), QNetworkSession::disconnectNotify(), QEventLoop::exec(), QDBusConnectionPrivate::handleObjectCall(), QDeclarativeEnginePrivate::init(), QGLSignalProxy::instance(), QMetaMethod::invoke(), QRawFontPrivate::isValid(), QBBScreen::newWindowCreated(), operator<<(), QScriptDebuggerBackendPrivate::postEvent(), QNetworkAccessHttpBackend::postRequest(), QStateMachinePrivate::processEvents(), qDBusAddTimeout(), qDBusAddWatch(), QDBusDefaultConnection::QDBusDefaultConnection(), qDBusIntrospectObject(), qDBusPropertyGet(), qDBusPropertyGetAll(), qDBusPropertySet(), qDBusRemoveTimeout(), qDBusRemoveWatch(), qDBusToggleWatch(), QEventDispatcherGlibPrivate::QEventDispatcherGlibPrivate(), QObject(), QSocks5BindStore::QSocks5BindStore(), QWaylandScreen::QWaylandScreen(), QEventDispatcherWin32::registerEventNotifier(), QEventDispatcherGlib::registerSocketNotifier(), QEventDispatcherWin32::registerSocketNotifier(), QEventDispatcherMac::registerSocketNotifier(), QEventDispatcherUNIX::registerSocketNotifier(), QEventDispatcherGlib::registerTimer(), QEventDispatcherWin32::registerTimer(), QEventDispatcherMac::registerTimer(), QEventDispatcherUNIX::registerTimer(), QDBusAdaptorConnector::relaySlot(), QWindowsFileSystemWatcherEngine::removePaths(), QSocks5BindStore::retrieve(), QDBusConnectionPrivate::sendWithReplyAsync(), QNetworkAccessManager::setCookieJar(), QEventDispatcherUNIX::setSocketNotifierPending(), QWindowsFileSystemWatcherEngine::stop(), thread(), QEventDispatcherWin32::unregisterEventNotifier(), QEventDispatcherGlib::unregisterSocketNotifier(), QEventDispatcherWin32::unregisterSocketNotifier(), QEventDispatcherMac::unregisterSocketNotifier(), QEventDispatcherUNIX::unregisterSocketNotifier(), QEventDispatcherGlib::unregisterTimer(), QEventDispatcherWin32::unregisterTimer(), QEventDispatcherUNIX::unregisterTimer(), QEventDispatcherGlib::unregisterTimers(), QEventDispatcherWin32::unregisterTimers(), QEventDispatcherMac::unregisterTimers(), QEventDispatcherUNIX::unregisterTimers(), QBBScreen::windowClosed(), QDBusConnectionPrivate::~QDBusConnectionPrivate(), and QWindowsFileSystemWatcherEngine::~QWindowsFileSystemWatcherEngine().

{
    return d_func()->threadData->thread;
}

timerEvent()

void QObject::timerEvent ( QTimerEvent *  event )

protectedvirtual

This event handler can be reimplemented in a subclass to receive timer events for the object.

QTimer provides a higher-level interface to the timer functionality, and also more general information about timers. The timer event is passed in the event parameter.

See also

startTimer(), killTimer(), event()

Reimplemented in QUnixSocketPrivate, QWSSoundServerPrivate, QDeclarativePixmapStore, QLineControl, QAbstractItemView, QSocks5BindStore, QWSServer, QGLBlurTextureCache, QSingleShotTimer, QTextEdit, QFontCache, QTextControl, QDBusConnectionPrivate, QComboBoxPrivateContainer, QPlainTextEdit, QDragManager, QMacStylePrivate, QDeclarativeMouseArea, QUnifiedTimer, QPMCache, QDeclarativeFlickable, QTreeView, QScriptDebugger, QMenu, QMainWindowLayout, QComboBoxPrivateScroller, QCoreFuriCuri, QListView, QMdiArea, QTableView, QAbstractSpinBox, QFileSystemModel, QAbstractSlider, QTreeModel, QTipLabel, QAbstractButton, QMenuBar, QTimeLine, QCoeFepInputContext, QDefaultAnimationDriver, QMdiSubWindow, QToolButton, QBalloonTip, QMotifStyle, QTextDocumentLayout, QNetworkAccessCache, QDeclarativeView, QPlastiqueStyle, QWindowsStyle, QTimer, QMacAnimateCursor, QTestEventLoop, and QCalendarTextNavigator.

Definition at line 1294 of file qobject.cpp.

Referenced by event(), QTextDocumentLayout::timerEvent(), QBalloonTip::timerEvent(), QMenuBar::timerEvent(), QTreeModel::timerEvent(), QAbstractSpinBox::timerEvent(), QMainWindowLayout::timerEvent(), QScriptDebugger::timerEvent(), QWSServer::timerEvent(), QTextControl::toHtml(), and QPlainTextEdit::toPlainText().

{
}

tr()

QString QObject::tr ( const char *  sourceText, const char *  disambiguation = 0, int  n = -1  )

static

Note

This class or function is reentrant.

Returns a translated version of sourceText, optionally based on a disambiguation string and value of n for strings containing plurals; otherwise returns sourceText itself if no appropriate translated string is available.

Example:

void MainWindow::createMenus()
{
    fileMenu = menuBar()->addMenu(tr("&File"));

...

If the same sourceText is used in different roles within the same context, an additional identifying string may be passed in disambiguation (0 by default). In Qt 4.4 and earlier, this was the preferred way to pass comments to translators.

Example:

MyWindow::MyWindow()
{
    QLabel *senderLabel = new QLabel(tr("Name:"));
    QLabel *recipientLabel = new QLabel(tr("Name:", "recipient"));

...

See Writing Source Code for Translation for a detailed description of Qt's translation mechanisms in general, and the Writing Source Code for Translation::Disambiguation{Disambiguation} section for information on disambiguation.

Warning

This method is reentrant only if all translators are installed before calling this method. Installing or removing translators while performing translations is not supported. Doing so will probably result in crashes or other undesirable behavior.

See also

trUtf8(), QApplication::translate(), QTextCodec::setCodecForTr(), {Internationalization with Qt}

Referenced by QAbstractSocketPrivate::_q_abortConnectionAttempt(), QUnixPrintWidgetPrivate::_q_btnBrowseClicked(), QProcessPrivate::_q_canReadStandardError(), QProcessPrivate::_q_canReadStandardOutput(), QProcessPrivate::_q_canWrite(), QPrintDialogPrivate::_q_collapseOrExpandDialog(), QAbstractSocketPrivate::_q_connectToNextAddress(), QFileDialogPrivate::_q_createDirectory(), QFileDialogPrivate::_q_deleteCurrent(), QFileDialogPrivate::_q_goToDirectory(), QScriptDebuggerPrivate::_q_goToLine(), QPrintDialogPrivate::_q_okClicked(), QUnixPrintWidgetPrivate::_q_printerChanged(), QProcessPrivate::_q_processDied(), QDeclarativeLoaderPrivate::_q_sourceLoaded(), QAbstractSocketPrivate::_q_startConnecting(), QWorkspacePrivate::_q_updateActions(), QFileDialogPrivate::_q_updateOkButton(), QNetworkReplyImpl::abort(), QHttp::abort(), QMessageBox::aboutQt(), QAccessibleButton::actionText(), QAccessibleMenu::actionText(), QAccessibleMenuBar::actionText(), QAccessibleToolButton::actionText(), QAccessibleMenuItem::actionText(), QAccessibleApplication::actionText(), QAccessibleTabBar::actionText(), QAccessibleComboBox::actionText(), QAccessibleTitleBar::actionText(), QPrintPropertiesDialog::addItemToOptions(), addKey(), QDeclarativeListModel::append(), QDeclarativeXmlListModelPrivate::append_role(), QSharedMemoryPrivate::attach(), QSQLiteDriver::beginTransaction(), QSQLite2Driver::beginTransaction(), QMYSQLDriver::beginTransaction(), QPSQLDriver::beginTransaction(), QODBCDriver::beginTransaction(), buttonDefaultText(), QMessageBox::buttonText(), QDeclarativeAnchorsPrivate::centerInChanged(), QUnixPrintWidgetPrivate::checkFields(), QDeclarativeAnchorsPrivate::checkHAnchorValid(), QDeclarativeAnchorsPrivate::checkHValid(), AVMediaObject::checkPlayer(), QDeclarativeAnchorsPrivate::checkVAnchorValid(), QDeclarativeAnchorsPrivate::checkVValid(), QScriptDebugger::clearConsoleAction(), QScriptDebugger::clearDebugOutputAction(), QScriptDebugger::clearErrorLogAction(), QNetworkReplyImpl::close(), QSQLiteDriver::close(), CloseButton::CloseButton(), QDB2Driver::commitTransaction(), QSQLiteDriver::commitTransaction(), QSQLite2Driver::commitTransaction(), QMYSQLDriver::commitTransaction(), QPSQLDriver::commitTransaction(), QODBCDriver::commitTransaction(), QDeclarativeGestureAreaParser::compile(), QDeclarativeConnectionsParser::compile(), QDeclarativeListModelParser::compile(), QDeclarativePropertyChangesParser::compileList(), QDeclarativeListModelParser::compileProperty(), QDeclarativeConnections::connectSignals(), QAbstractSocket::connectToHostImplementation(), QScrollBar::contextMenuEvent(), QDialog::contextMenuEvent(), QAbstractSpinBox::contextMenuEvent(), QScriptDebugger::continueAction(), QFile::copy(), QSharedMemory::create(), QSharedMemoryPrivate::create(), QDialogButtonBoxPrivate::createButton(), QProcessPrivate::createChannel(), QmlJSDebugger::LiveSelectionTool::createContextMenu(), QDeclarativeTextInput::createCursor(), QDeclarativeComponent::createObject(), QDeclarativeAbstractAnimationPrivate::createProperty(), QUndoGroup::createRedoAction(), QUndoStack::createRedoAction(), QTextControl::createStandardContextMenu(), QLineEdit::createStandardContextMenu(), QScriptDebugger::createStandardMenu(), QMdiSubWindowPrivate::createSystemMenu(), QUndoGroup::createUndoAction(), QUndoStack::createUndoAction(), QMessageBox::critical(), QKeySequencePrivate::decodeString(), QDeclarativeItemModule::defineModule(), QDeclarativeUtilModule::defineModule(), QDeclarativeItemModule::defineModuleCompat(), QDeclarativeUtilModule::defineModuleCompat(), QMultiInputContextPlugin::description(), QInputContextFactory::description(), QLocalSocketPrivate::destroyPipeHandles(), QSharedMemoryPrivate::detach(), QMultiInputContextPlugin::displayName(), QInputContextFactory::displayName(), QDeclarativeParentChangePrivate::doChange(), QUdpSocketPrivate::doEnsureInitialized(), QDeclarativeTypeData::done(), QMotifStyle::drawComplexControl(), QCommonStyle::drawControl(), QMotifStyle::drawControl(), QFtpPI::dtpConnectState(), QKeySequencePrivate::encodeString(), QODBCDriver::endTrans(), QInputDialogPrivate::ensureLayout(), QFtpPI::error(), QPluginLoader::errorString(), QLibrary::errorString(), QNetworkSession::errorString(), QSslError::errorString(), QIODevice::errorString(), QNetworkSessionPrivateImpl::errorString(), QMDIControl::event(), QWorkspace::eventFilter(), QDialog::exec(), QScriptEdit::extraAreaMouseEvent(), QDeclarativeAnchorsPrivate::fillChanged(), QScriptDebugger::findInScriptAction(), QScriptDebugger::findNextInScriptAction(), QScriptDebugger::findPreviousInScriptAction(), QNetworkReplyImplPrivate::finished(), QNetworkSessionManagerPrivate::forceSessionClose(), QHostInfoAgent::fromName(), QNetworkAccessFtpBackend::ftpDone(), QDateTimeEditPrivate::getAmPmText(), getFullPath(), QScriptDebugger::goToLineAction(), QSystemSemaphorePrivate::handle(), QSharedMemoryPrivate::handle(), QDirModel::headerData(), QFileSystemModel::headerData(), QBBInputContext::identifierName(), QColorDialogPrivate::init(), QFontDialogPrivate::init(), QLocalSocketPrivate::init(), QPrintPreviewDialogPrivate::init(), QWorkspacePrivate::init(), QSharedMemoryPrivate::initKey(), QAbstractSocketPrivate::initSocketLayer(), QSslSocketBackendPrivate::initSslContext(), QDeclarativeListModel::insert(), QScriptDebugger::interruptAction(), QLibraryPrivate::isPlugin(), QDeclarativeVisualDataModel::item(), jump(), DetailButton::label(), QTcpServer::listen(), QLocalServer::listen(), QLibraryPrivate::load_sys(), QDeclarativeComponent::loadUrl(), QAccessibleGroupBox::localizedName(), QSharedMemory::lock(), QGraphicsView::mapFromScene(), QGraphicsView::mapToScene(), QGraphicsViewPrivate::mapToScene(), QDeclarativeListModel::move(), QFileSystemModelPrivate::myComputer(), QNetworkAccessFtpBackend::open(), QSQLite2Driver::open(), QSQLiteDriver::open(), QOCIDriver::open(), QTDSDriver::open(), QDB2Driver::open(), QMYSQLDriver::open(), QPSQLDriver::open(), QODBCDriver::open(), QPrintDialogPrivate::openWindowsPrintDialogModally(), QProcessPrivate::pipeWriterBytesToWrite(), AVMediaObject::play(), populatePaperSizes(), QNetworkAccessHttpBackend::postRequest(), QFtpPI::processReply(), QDeclarativePropertyChangesPrivate::property(), QBooleanComboBox::QBooleanComboBox(), QDeclarativeLayoutMirroringAttached::QDeclarativeLayoutMirroringAttached(), qExtractSecurityPolicyFromString(), QFtp::QFtp(), qmlsqldatabase_change_version(), qmlsqldatabase_executeSql_outsidetransaction(), qmlsqldatabase_executeSql_readonly(), qmlsqldatabase_open_sync(), qmlsqldatabase_transaction_shared(), QmlJSDebugger::QmlToolBar::QmlToolBar(), QMultiInputContext::QMultiInputContext(), QOCIDriver::QOCIDriver(), QPageSetupWidget::QPageSetupWidget(), QScriptBreakpointsWidget::QScriptBreakpointsWidget(), QScriptDebuggerCodeFinderWidget::QScriptDebuggerCodeFinderWidget(), QScriptNewBreakpointWidget::QScriptNewBreakpointWidget(), qt_create_commandline(), qt_create_pipe(), qt_detectRTLLanguage(), qt_getLprPrinters(), qt_mac_make_filters_list(), qt_mac_menu_merge_action(), qt_mac_menu_merge_text(), qt_parse_pattern(), qt_parseEtcLpMember(), qt_parsePrinterDesc(), qt_parsePrintersConf(), qt_perhapsAddPrinter(), qt_setWindowTitle_helperHelper(), qt_terminateApp(), qt_win_make_filters_list(), QTgaFile::QTgaFile(), QDeclarativeXmlListModel::queryError(), QUndoModel::QUndoModel(), QUnicodeControlCharacterMenu::QUnicodeControlCharacterMenu(), QDeclarativeListModel::remove(), QFile::rename(), QLibraryPrivate::resolve_sys(), QDeclarativeTypeData::resolveTypes(), QColorDialogPrivate::retranslateStrings(), QProgressDialogPrivate::retranslateStrings(), QErrorMessagePrivate::retranslateStrings(), QFontDialogPrivate::retranslateStrings(), QFileDialogPrivate::retranslateStrings(), QDialogButtonBoxPrivate::retranslateStrings(), QColorShower::retranslateStrings(), QFileDialogPrivate::retranslateWindowTitle(), QDB2Driver::rollbackTransaction(), QSQLiteDriver::rollbackTransaction(), QSQLite2Driver::rollbackTransaction(), QMYSQLDriver::rollbackTransaction(), QPSQLDriver::rollbackTransaction(), QODBCDriver::rollbackTransaction(), QScriptDebugger::runToCursorAction(), QScriptDebugger::runToNewScriptAction(), QFtpPI::sendCommands(), QDeclarativeListModel::set(), QDeclarativeBehavior::setAnimation(), QDB2Driver::setAutoCommit(), QDeclarativeFlipable::setBack(), QDeclarativeAnchors::setCenterIn(), QFileSystemModel::setData(), QDeclarativePauseAnimation::setDuration(), QDeclarativePropertyAnimation::setDuration(), QDeclarativeAnchorAnimation::setDuration(), QLocalServerPrivate::setError(), QStateMachinePrivate::setError(), QNativeSocketEnginePrivate::setError(), QSocks5SocketEnginePrivate::setErrorState(), QLocalSocketPrivate::setErrorString(), QSharedMemoryPrivate::setErrorString(), QPluginLoader::setFileName(), QDeclarativeAnchors::setFill(), QDeclarativeFlipable::setFront(), QFileDialog::setNameFilters(), QMdiSubWindowPrivate::setNewWindowTitle(), QDeclarativeListModel::setProperty(), QTcpServer::setSocketDescriptor(), QAbstractSocket::setSocketDescriptor(), AVMediaObject::setSource(), QPrintDialogPrivate::setupOptions(), QPrintDialogPrivate::setupPaper(), QSidebar::showContextMenu(), QWorkspacePrivate::showMaximizeControls(), QMessageBoxPrivate::showOldMessageBox(), QFileDialogComboBox::showPopup(), showToolTip(), QDirModelPrivate::size(), QFileSystemModelPrivate::size(), QHttpSocketEngine::slotSocketError(), QHttpSocketEngine::slotSocketReadNotification(), QSoftKeyManager::standardSoftKeyText(), QScriptEngineDebugger::standardWindow(), QProcess::start(), QDeclarativeTextInputPrivate::startCreatingCursor(), QSslSocketBackendPrivate::startHandshake(), QProcessPrivate::startProcess(), QScriptDebugger::stepIntoAction(), QScriptDebugger::stepOutAction(), QScriptDebugger::stepOverAction(), QCommonStyle::subElementRect(), QMotifStyle::subElementRect(), QPSQLDriver::subscribeToNotificationImplementation(), QCommonStylePrivate::tabLayout(), tabTextFor(), QAccessibleAbstractSpinBox::text(), QAccessibleDoubleSpinBox::text(), QAccessibleScrollBar::text(), QAccessibleSlider::text(), QAccessibleDial::text(), QAccessibleTabBar::text(), QAccessibleComboBox::text(), QScriptDebugger::toggleBreakpointAction(), QmlJSDebugger::ToolBarColorBox::ToolBarColorBox(), QDeclarativeParentAnimation::transition(), translateWSAError(), QSslSocketBackendPrivate::transmit(), QSharedMemoryPrivate::tryLocker(), QPluginLoader::unload(), QLibraryPrivate::unload_sys(), QSharedMemory::unlock(), QFile::unmap(), QPSQLDriver::unsubscribeFromNotificationImplementation(), QDeclarativeBinding::update(), QDeclarativeAnchorsPrivate::updateHorizontalAnchors(), QDeclarativeAnchorsPrivate::updateVerticalAnchors(), QUnixPrintWidgetPrivate::updateWidget(), QProcessPrivate::waitForBytesWritten(), QAbstractSocket::waitForConnected(), QProcessPrivate::waitForFinished(), QProcessPrivate::waitForReadyRead(), QProcessPrivate::waitForStarted(), QAbstractSocket::writeData(), QProcess::writeData(), and QmlJSDebugger::ZoomTool::ZoomTool().

trUtf8()

QString QObject::trUtf8 ( const char *  sourceText, const char *  disambiguation = 0, int  n = -1  )

static

Note

This class or function is reentrant.

Returns a translated version of sourceText, or QString::fromUtf8(sourceText) if there is no appropriate version. It is otherwise identical to tr(sourceText, disambiguation, n).

Note that using the Utf8 variants of the translation functions is not required if CODECFORTR is already set to UTF-8 in the qmake project file and QTextCodec::setCodecForTr("UTF-8") is used.

Warning

This method is reentrant only if all translators are installed before calling this method. Installing or removing translators while performing translations is not supported. Doing so will probably result in crashes or other undesirable behavior.

For portability reasons, we recommend that you use escape sequences for specifying non-ASCII characters in string literals to trUtf8(). For example:

label->setText(tr("F\374r \310lise"));

See also

tr(), QApplication::translate(), {Internationalization with Qt}

userData()

QObjectUserData * QObject::userData

(

uint

id

)

const

Warning

This function is not part of the public interface.

Definition at line 4016 of file qobject.cpp.

Referenced by hb_canRender(), hb_getAdvances(), hb_getFontMetric(), hb_getGlyphMetrics(), hb_getPointInOutline(), hb_stringToGlyphs(), QScriptSyntaxHighlighter::highlightBlock(), and QTextBlock::operator<().

{
    Q_D(const QObject);
    if (!d->extraData)
        return 0;
    if ((int)id < d->extraData->userData.size())
        return d->extraData->userData.at(id);
    return 0;
}

Friends and Related Functions

QApplication

friend class QApplication

friend

Definition at line 325 of file qobject.h.

QApplicationPrivate

friend class QApplicationPrivate

friend

Definition at line 326 of file qobject.h.

QCoreApplication

friend class QCoreApplication

friend

Definition at line 327 of file qobject.h.

QCoreApplicationPrivate

friend class QCoreApplicationPrivate

friend

Definition at line 328 of file qobject.h.

Referenced by QCoreApplication::QCoreApplication().

qFindChildqFindChildren()

T qFindChildqFindChildren ( const QObject *  obj, const QString &  name, const QObject *  obj, const QString &  name  )

related

This function is equivalent to {obj}->findChild<T>(name).

Note

This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code.

See also

QObject::findChild()

qFindChildrenqFindChildren() [1/2]

QList< T > qFindChildrenqFindChildren ( const QObject *  obj, const QString &  name, const QObject *  obj, const QString &  name  )

related

This function is equivalent to {obj}->findChildren<T>(name).

Note

This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code.

See also

QObject::findChildren()

qFindChildrenqFindChildren() [2/2]

QList< T > qFindChildrenqFindChildren ( const QObject *  obj, const QRegExp &  regExp, const QObject *  obj, const QRegExp &  regExp  )

related

This function is equivalent to {obj}->findChildren<T>(regExp).

Note

This function was provided as a workaround for MSVC 6 which did not support member template functions. It is advised to use the other form in new code.

See also

QObject::findChildren()

QMetaObject

friend struct QMetaObject

friend

Definition at line 324 of file qobject.h.

qobject_cast()

T * qobject_cast< T *> ( QObject *  object )

related

Returns the given object cast to type T if the object is of type T (or of a subclass); otherwise returns 0. If object is 0 then it will also return 0.

The class T must inherit (directly or indirectly) QObject and be declared with the Q_OBJECT macro.

A class is considered to inherit itself.

Example:

QObject *obj = new QTimer;          // QTimer inherits QObject

QTimer *timer = qobject_cast<QTimer *>(obj);
// timer == (QObject *)obj

QAbstractButton *button = qobject_cast<QAbstractButton *>(obj);
// button == 0

The qobject_cast() function behaves similarly to the standard C++ dynamic_cast(), with the advantages that it doesn't require RTTI support and it works across dynamic library boundaries.

qobject_cast() can also be used in conjunction with interfaces; see the Plug & Paint example for details.

Warning

If T isn't declared with the Q_OBJECT macro, this function's return value is undefined.

See also

QObject::inherits()

Definition at line 375 of file qobject.h.

Referenced by QMenuPrivate::_q_actionTriggered(), QToolBoxPrivate::_q_buttonClicked(), QWSServerPrivate::_q_doClient(), _q_paintItem(), QNetworkAccessManagerPrivate::_q_replyFinished(), QNetworkAccessManagerPrivate::_q_replySslErrors(), QHttpPrivate::_q_slotSendRequest(), QDeclarativeLoaderPrivate::_q_sourceLoaded(), QParallelAnimationGroupPrivate::_q_uncontrolledAnimationFinished(), QFontComboBoxPrivate::_q_updateModel(), QToolBar::actionEvent(), QWidgetPrivate::activateChildLayoutsRecursively(), QMdiArea::addSubWindow(), QMacStylePrivate::addWidget(), QPushButtonPrivate::adjustedMenuPosition(), QDeclarativeParticleMotionWander::advance(), QAbstractTextDocumentLayout::anchorAt(), QWidgetAnimator::animationFinished(), QMainWindowLayout::animationFinished(), QPlainTextEditPrivate::append(), QDeclarativeAnimationGroupPrivate::append_animation(), QDeclarativeXmlListModelPrivate::append_role(), ShaderEffectSource::attachSourceItem(), QScriptEngine::availableExtensions(), axc_FilterProc(), QPlainTextEditControl::blockBoundingRect(), QPlainTextEdit::blockBoundingRect(), QScriptBreakpointsWidget::breakpointsModel(), buddyString(), QDeclarativeContents::calcHeight(), QDeclarativeContents::calcWidth(), QPlainTextEditControl::canInsertFromMimeData(), QTextEditControl::canInsertFromMimeData(), QDeclarativeBoundSignal::cast(), QmlJSDebugger::QmlToolBar::changeAnimationSpeed(), QDockWidget::changeEvent(), QWorkspaceChild::changeEvent(), QX11EmbedWidgetPrivate::checkActivateWindow(), QToolBarLayout::checkUsePopupMenu(), QWidgetPrivate::childAt_helper(), QWidgetPrivate::childAtRecursiveHelper(), QStatePrivate::childStates(), childWidgets(), QDeclarativeAnimationGroupPrivate::clear_animation(), QDeclarativeContents::complete(), AVBackend::connectNodes(), AccessibleFactory::create(), QDeclarativeListViewPrivate::createComponentItem(), QDeclarativeTextInput::createCursor(), QScriptDebuggerLocalsItemDelegate::createEditor(), QScriptBreakpointsItemDelegate::createEditor(), QDeclarativePathViewPrivate::createHighlight(), QToolBarLayout::createItem(), QPlainTextEditControl::createMimeDataFromSelection(), QTextEditControl::createMimeDataFromSelection(), QWidgetPrivate::createRecursively(), QDeclarativeListViewPrivate::createSection(), QWidgetPrivate::createWinId(), QScriptDebuggerCodeWidget::currentView(), QDeclarativeFlickablePrivate::data_append(), defaultWidgetAction(), QGLWindowSurface::deleted(), ShaderEffectSource::detachSourceItem(), QAudioInputPrivate::deviceReady(), AVBackend::disconnectNodes(), do_dbus_call(), QWindowsVistaStyle::drawComplexControl(), QCommonStyle::drawComplexControl(), QWindowsCEStyle::drawComplexControl(), QWindowsVistaStyle::drawControl(), QMacStyle::drawControl(), QTextDocumentLayout::drawInlineObject(), QGraphicsScenePrivate::drawItemHelper(), QGraphicsScene::drawItems(), QWindowsVistaStyle::drawPrimitive(), QMacStyle::drawPrimitive(), QListModel::dropMimeData(), QTableModel::dropMimeData(), QScriptEditExtraArea::editor(), QAbstractItemView::editorDestroyed(), QHttpNetworkConnectionChannel::ensureConnection(), QIODevice::errorString(), QFontComboBox::event(), QDockWidget::event(), QLabel::event(), QToolBar::event(), QDialogButtonBox::event(), QWidget::event(), QX11EmbedWidget::eventFilter(), QStyledItemDelegate::eventFilter(), QPlastiqueStyle::eventFilter(), QItemDelegate::eventFilter(), QAxHostWidget::eventFilter(), QCompleter::eventFilter(), QMdiArea::eventFilter(), QScriptDebuggerLocalsItemDelegate::eventFilter(), QToolBarLayout::expandedSize(), QToolBarLayout::expandingDirections(), QAudioInputPrivate::feedback(), QCompletionEngine::filterHistory(), find_child(), findMenuBar(), fixToolBarOrientation(), QPushButton::focusInEvent(), QPushButton::focusOutEvent(), QAbstractTextDocumentLayout::format(), QAbstractTextDocumentLayout::formatIndex(), QAudioOutputPrivate::freeBlocks(), QGraphicsScenePrivate::gestureEventHandler(), getEngineFromId(), getImage(), QWidgetPrivate::getOpaqueChildren(), getPixmap(), QMacInputContext::globalEventProcessor(), QApplicationPrivate::globalEventProcessor(), QCalendarView::handleMouseEvent(), QWidgetPrivate::hideChildren(), QStatePrivate::historyStates(), QPlainTextEditControl::hitTest(), if(), QHttp::ignoreSslErrors(), QScriptEngine::importExtension(), QWidgetPrivate::inheritStyle(), QHttpNetworkConnectionChannel::init(), QToolBar::initStyleOption(), InputPrivate::InputPrivate(), QListModel::insert(), QPlainTextEditControl::insertFromMimeData(), QTextEditControl::insertFromMimeData(), QListModel::insertRows(), QDeclarativeFlickablePrivate::isOutermostPressDelay(), QWidgetPrivate::isOverlapped(), isTreeView(), QDeclarativeVisualDataModel::item(), QListWidget::items(), QTableWidget::items(), QToolBarLayout::layoutActions(), QGraphicsScenePrivate::leaveScene(), QDeclarativeTextEdit::loadCursorDelegate(), QDeclarativeInspectorService::loadInspectorPlugin(), QTextDocument::loadResource(), QScriptDebuggerLocalsWidget::localsModel(), QDeclarativeItem::mapFromItem(), QDeclarativeItem::mapToItem(), ShaderEffectSource::markSourceItemDirty(), QUnicodeControlCharacterMenu::menuActionTriggered(), QMainWindow::menuBar(), QDeclarativeEngineDebugService::messageReceived(), QListModel::mimeData(), QTableModel::mimeData(), QListModel::mimeTypes(), QTableModel::mimeTypes(), QDockWidgetLayout::minimumSize(), QDockWidgetLayout::minimumTitleWidth(), QCalendarView::mouseDoubleClickEvent(), QCalendarView::mouseMoveEvent(), QSizeGrip::mousePressEvent(), QCalendarPopup::mousePressEvent(), QCalendarView::mousePressEvent(), QCalendarView::mouseReleaseEvent(), QToolBarLayout::movable(), QCalendarView::moveCursor(), QAbstractButtonPrivate::moveFocus(), QNetworkManagerEngine::newConnection(), QApplication::notify(), QTextFrame::iterator::operator++(), QTextFrame::iterator::operator--(), OutputPrivate::OutputPrivate(), QTextEditPrivate::paint(), QScriptDebuggerLocalsItemDelegate::paint(), QGraphicsTextItem::paint(), QWidgetPrivate::paintBackground(), QDockWidget::paintEvent(), QWidgetPrivate::paintSiblingsRecursive(), QGraphicsWidget::paintWindowFrame(), QDeclarativeItem::parentItem(), QAbstractState::parentState(), QFSCompleter::pathFromIndex(), QCompleter::pathFromIndex(), QMacStyle::pixelMetric(), QStyleSheetStyle::pixelMetric(), QMainWindowLayout::plug(), QPlastiqueStyle::polish(), QStyleSheetStyle::polish(), QGtkStyle::polish(), QDBusAdaptorConnector::polish(), QMenu::popup(), QToolButtonPrivate::popupTimerDone(), QTextDocumentLayout::positionInlineObject(), QHttpPrivate::postMoreData(), QWidgetPrivate::propagatePaletteChange(), q_createNativeChildrenAndSetParent(), QAction::QAction(), qDBusFindAdaptorConnector(), QDeclarativeKeysAttached::QDeclarativeKeysAttached(), QFontComboBox::QFontComboBox(), qgraphicsobject_autoParent(), QIODevice::QIODevice(), qmlxmlhttprequest_abort(), qmlxmlhttprequest_getAllResponseHeaders(), qmlxmlhttprequest_getResponseHeader(), qmlxmlhttprequest_onreadystatechange(), qmlxmlhttprequest_open(), qmlxmlhttprequest_readyState(), qmlxmlhttprequest_responseText(), qmlxmlhttprequest_responseXML(), qmlxmlhttprequest_send(), qmlxmlhttprequest_setRequestHeader(), qmlxmlhttprequest_status(), qmlxmlhttprequest_statusText(), QScriptDBusInterfaceConstructor::qscript_call(), qt_aqua_get_known_size(), qt_guiPlatformPlugin(), qt_mac_buttonIsRenderedFlat(), QSignalEventGenerator::qt_metacall(), QToolBarLayout::QToolBarLayout(), QtWndProc(), QWidgetResizeHandler::QWidgetResizeHandler(), QWinEventNotifier::QWinEventNotifier(), QAbstractTextDocumentLayout::registerHandler(), QTextEditPrivate::relayoutDocument(), QPlainTextEditPrivate::relayoutDocument(), QNetworkManagerEngine::removeConnection(), QMacStylePrivate::removeWidget(), QmlJSDebugger::QDeclarativeViewInspector::reparentQmlObject(), QTextDocumentLayout::resizeInlineObject(), QDeclarativeParentChange::saveCurrentValues(), QAxScriptManager::scriptError(), QScriptDebuggerScriptsWidget::scriptsModel(), QDeclarativeWorkerScriptEnginePrivate::scriptValueToVariant(), QInputContext::sendEvent(), QSoftKeyManager::sendKeyEvent(), QDeclarativePathView::sendMouseEvent(), QDeclarativeMouseArea::sendMouseEvent(), QDeclarativeFlickable::sendMouseEvent(), QDeclarativePinchArea::sendMouseEvent(), QDeclarativeTextInputPrivate::sendMouseEventToInputContext(), QHttpNetworkConnectionChannel::sendRequest(), QWidget::setAttribute(), QGraphicsScene::setBspTreeDepth(), QCalendarPopup::setCalendarWidget(), QTableModel::setData(), QMessageBox::setDetailedText(), QWidget::setDisabled(), QPlainTextEdit::setDocument(), QWinEventNotifier::setEnabled(), QWidgetPrivate::setEnabled_helper(), QToolBarLayout::setExpanded(), QDockWidget::setFeatures(), QAction::setFont(), QToolBarLayout::setGeometry(), QDockWidgetLayout::setGeometry(), QTableModel::setHorizontalHeaderItem(), QToolBar::setIconSize(), QTableModel::setItem(), QTableModel::setItemData(), QGraphicsScene::setItemIndexMethod(), QComboBoxPrivateContainer::setItemView(), QWidgetPrivate::setLayoutDirection_helper(), QWidgetPrivate::setLocale_helper(), QMainWindow::setMenuBar(), QCompleter::setModel(), QComboBox::setModelColumn(), QScriptDebuggerLocalsItemDelegate::setModelData(), QScriptBreakpointsItemDelegate::setModelData(), ShaderEffectItem::setSource(), QWidgetPrivate::setStyle_helper(), QApplication::setStyleSheet(), QWidget::setStyleSheet(), QDockWidget::setTitleBarWidget(), QWidgetPrivate::setUpdatesEnabled_helper(), QTableModel::setVerticalHeaderItem(), QDialog::setVisible(), QDockWidget::setWidget(), QWidgetPrivate::setWindowIcon_helper(), QFontComboBox::setWritingSystem(), QGLShaderProgram::shaderDestroyed(), QMdi::ControlContainer::showButtonsInMenuBar(), QWidgetPrivate::showChildren(), QWidget::showFullScreen(), QWidget::showMaximized(), QWidget::showNormal(), QComboBox::showPopup(), QDockWidgetLayout::sizeFromContent(), QMacStyle::sizeFromContents(), QPushButton::sizeHint(), QDockWidgetLayout::sizeHint(), QComboBoxPrivateContainer::spacing(), QFSCompleter::splitPath(), QCompleter::splitPath(), QMainWindowLayout::statusBar(), QWindowsXPStyle::styleHint(), QWindowsStyle::styleHint(), QCommonStyle::subElementRect(), QMacStyle::subElementRect(), QWidgetPrivate::subtractOpaqueSiblings(), QListModel::supportedDropActions(), QTableModel::supportedDropActions(), QScriptDebuggerLocalsModel::sync(), QMainWindowLayout::tabChanged(), QTableWidgetPrivate::tableModel(), QToolBarLayout::takeAt(), QTextBlock::textList(), QDeclarativeFlickable::timerEvent(), QDockWidget::titleBarWidget(), QmlJSDebugger::AbstractLiveEditTool::titleForItem(), QDockWidgetLayout::titleHeight(), toolbarInUnifiedToolBar(), QmlJSDebugger::AbstractLiveEditTool::toQDeclarativeItem(), QDeclarativeItemPrivate::transform_append(), QDeclarativeItemPrivate::transform_at(), QDeclarativeItemPrivate::transform_clear(), QDeclarativeItemPrivate::transform_count(), QStatePrivate::transitions(), QTreeWidgetPrivate::treeModel(), QPlastiqueStyle::unpolish(), QNetworkManagerEngine::updateAccessPoint(), QNetworkConfigurationManagerPrivate::updateConfigurations(), QNetworkManagerEngine::updateConnection(), QMenuBarPrivate::updateCornerWidgetToolBar(), QFactoryLoader::updateDir(), QWidgetPrivate::updateFont(), QToolBarLayout::updateGeomArray(), QToolBarLayout::updateMarginAndSpacing(), QWorkspaceChild::updateMask(), QMessageBoxPrivate::updateSize(), QStyleSheetStyle::updateStyleSheetFont(), QComboBoxPrivateContainer::updateTopBottomMargin(), QScriptBreakpointsItemDelegate::validateInput(), QPlainTextEditPrivate::verticalOffset(), QTreeModel::view(), QMdiArea::viewportEvent(), QHeaderView::viewportEvent(), QWizardHeader::vistaDisabled(), waitForPopup(), QDockWidget::widget(), QWorkspace::windowList(), QDeclarativeContents::~QDeclarativeContents(), QToolBar::~QToolBar(), and QWorkspaceChild::~QWorkspaceChild().

{
#if !defined(QT_NO_QOBJECT_CHECK)
    reinterpret_cast<T>(object)->qt_check_for_QOBJECT_macro(*reinterpret_cast<T>(object));
#endif
    return static_cast<T>(reinterpret_cast<T>(object)->staticMetaObject.cast(object));
}

QObjectList()

QObjectList

related

Synonym for QList<QObject *>.

qt_find_obj_child()

void * qt_find_obj_child ( QObject *  parent, const char *  type, const QString &  name  )

related

Returns a pointer to the object named name that inherits type and with a given parent.

Returns 0 if there is no such child.

QLineEdit *lineEdit = static_cast<QLineEdit *>(
        qt_find_obj_child(myWidget, "QLineEdit", "my line edit"));
if (lineEdit)
    lineEdit->setText("Default");

Definition at line 700 of file qobject.cpp.

{
    QObjectList list = parent->children();
    if (list.size() == 0) return 0;
    for (int i = 0; i < list.size(); ++i) {
        QObject *obj = list.at(i);
        if (name == obj->objectName() && obj->inherits(type))
            return obj;
    }
    return 0;
}

QThreadData

friend class QThreadData

friend

Definition at line 330 of file qobject.h.

Referenced by moveToThread().

QWidget

friend class QWidget

friend

Definition at line 329 of file qobject.h.

Referenced by QX11Data::clipboardReadIncrementalProperty(), QClipboardData::QClipboardData(), qt_tablet_init(), setupOwner(), and QScriptEngineDebugger::standardWindow().

Properties

d_ptr

QScopedPointer<QObjectData> QObject::d_ptr

protected

Definition at line 320 of file qobject.h.

Referenced by QDirectFBScreen::createDFBSurface(), QVFbScreen::depth(), QDirectFBScreen::dfb(), QDirectFBScreen::dfbDisplayLayer(), QDirectFBScreen::directFBFlags(), QVFbScreenPrivate::disconnect(), QVFbScreen::format(), QVFbScreen::geometry(), QMetaObject::metacall(), QWidgetPrivate::paintBackground(), QVFbScreen::physicalSize(), QDeclarativeBoundSignalParameters::QDeclarativeBoundSignalParameters(), QObject(), QSettings::QSettings(), QSignalEventGenerator::qt_metacall(), QSettings::registerFormat(), QDBusAdaptorConnector::relaySlot(), QDirectFBScreen::releaseDFBSurface(), QGraphicsScene::render(), QGraphicsView::render(), QVFbScreen::screenImage(), QDeclarativeGraphics_DerivedObject::setParent_noEvent(), QTreeModel::sortItems(), QtFriendlyLayoutWidget::wasDeleted(), QIODevice::write(), QGraphicsItem::~QGraphicsItem(), and QScriptEngine::~QScriptEngine().

objectName

QString QObject::objectName

private

the name of this object

You can find an object by name (and type) using findChild(). You can find a set of objects with findChildren().

qDebug("MyClass::setPrecision(): (%s) invalid precision %f",
       qPrintable(objectName()), newPrecision);

By default, this property contains an empty string.

See also

metaObject(), QMetaObject::className()

Definition at line 114 of file qobject.h.

Referenced by QAxScriptManager::addObject(), QAccessibleCalendarWidget::calendarView(), QCoreApplicationPrivate::checkReceiverThread(), QMetaObject::connectSlotsByName(), err_info_about_objects(), QScript::QObjectDelegate::getOwnPropertyDescriptor(), QScript::QObjectDelegate::getOwnPropertySlot(), QDBusConnectionPrivate::handleObjectCall(), killTimer(), QAccessibleCalendarWidget::navigationBar(), QAxScriptManager::objectDestroyed(), QDeclarativeDebugService::objectToString(), operator<<(), qax_create_object_wrapper(), QScript::qobjectProtoFuncFindChildren(), QScript::qobjectProtoFuncToString(), QTest::qSignalDumperCallback(), QTest::qSignalDumperCallbackSlot(), qt_find_obj_child(), qt_qFindChild_helper(), qt_qFindChildren_helper(), QCoreApplicationPrivate::removePostedEvent(), setObjectName(), QDBusPendingCallPrivate::setReplyCallback(), QDeclarativeObjectScriptClass::tostring(), and QDeclarativeEngineDebugService::valueContents().

staticMetaObject

QObject::staticMetaObject

static

This variable stores the meta-object for the class.

A meta-object contains information about a class that inherits QObject, e.g. class name, superclass name, properties, signals and slots. Every class that contains the Q_OBJECT macro will also have a meta-object.

The meta-object information is required by the signal/slot connection mechanism and the property system. The inherits() function also makes use of the meta-object.

If you have a pointer to an object, you can use metaObject() to retrieve the meta-object associated with that object.

Example:

QPushButton::staticMetaObject.className();  // returns "QPushButton"

QObject *obj = new QPushButton;
obj->metaObject()->className();             // returns "QPushButton"

See also

metaObject()

Definition at line 128 of file qobject.h.

Referenced by QDeclarativeCompiler::buildObject(), QDeclarativeCompiler::buildPropertyObjectAssignment(), QDBusAbstractInterface::callWithArgumentList(), QFontDialogPrivate::canBeNativeDialog(), QFileDialogPrivate::canBeNativeDialog(), QDeclarativePropertyPrivate::canConvert(), classIDL(), QDeclarativeListModelParser::compileProperty(), QDBusConnectionPrivate::connectRelay(), QDeclarativePathView::createdItem(), QDeclarativeItemPrivate::data_append(), QMetaObjectBuilder::deserialize(), QDBusConnectionPrivate::disconnectRelay(), findSlot(), QDeclarativeCompiler::genObject(), QDeclarativePathViewPrivate::getItem(), QDeclarativeRectanglePrivate::getPen(), QDeclarativeBorderImagePrivate::getScaleGrid(), QDeclarativeFlickablePrivate::init(), QDeclarativePathViewPrivate::init(), QtDBusScriptPlugin::initialize(), QAxServerBase::isPropertyExposed(), QDeclarativeKeysAttached::keyPressed(), QDeclarativeBorderImage::load(), QDeclarativeImageBase::load(), QSignalEventGenerator::metaObject(), QDBusInterface::metaObject(), QAxObject::parentMetaObject(), QAxWidget::parentMetaObject(), QStyleSheetStyle::polish(), QBBButtonEventNotifier::QBBButtonEventNotifier(), qDBusInterfaceInObject(), qDBusIntrospectObject(), qDBusUpdateDispatchStatus(), QDeclarativeBoundSignalParameters::QDeclarativeBoundSignalParameters(), QDeclarativeCompiledBindings::QDeclarativeCompiledBindings(), QDeclarativeExpression::QDeclarativeExpression(), QDeclarativeFastProperties::QDeclarativeFastProperties(), QDeclarativePixmapReply::QDeclarativePixmapReply(), QDeclarativeWatchProxy::QDeclarativeWatchProxy(), QMetaObjectBuilderPrivate::QMetaObjectBuilderPrivate(), QScript::qobjectProtoFuncToString(), QSignalSpy::QSignalSpy(), QtWndProc(), readAllProperties(), QDBusAdaptorConnector::relay(), QDBusAdaptorConnector::relaySignal(), QDBusConnectionPrivate::relaySignal(), resolveClassName(), QDeclarativePixmapReader::run(), QDBusAbstractAdaptor::setAutoRelaySignals(), QDBusConnectionPrivate::setConnection(), QTextControlPrivate::setContent(), QDeclarativeRectangle::setGradient(), QDeclarativeBorderImage::setGridScaledImage(), QDeclarativeVisualDataModel::setModel(), QmlJSDebugger::InspectorProtocol::toString(), QPropertyAnimation::updateState(), QGraphicsView::viewportEvent(), and QDBusMetaObjectGenerator::write().

staticQtMetaObject

const QMetaObject QObject::staticQtMetaObject

staticprotected

Definition at line 322 of file qobject.h.

Referenced by StaticQtMetaObject::get(), QMetaObject::property(), and QDeclarativeBoundSignalParameters::QDeclarativeBoundSignalParameters().

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The documentation for this class was generated from the following files:

• /src/corelib/kernel/qobject.h
• /src/corelib/kernel/qobject.cpp