QPropertyAnimation Class Reference

The QPropertyAnimation class animates Qt properties. More...

#include <qpropertyanimation.h>

Inheritance diagram for QPropertyAnimation:

Public Functions
QByteArray	propertyName () const
	QPropertyAnimation (QObject *parent=0)
	Construct a QPropertyAnimation object. More...
	QPropertyAnimation (QObject *target, const QByteArray &propertyName, QObject *parent=0)
	Construct a QPropertyAnimation object. More...
void	setPropertyName (const QByteArray &propertyName)
void	setTargetObject (QObject *target)
QObject *	targetObject () const
	~QPropertyAnimation ()
	Destroys the QPropertyAnimation instance. More...
Public Functions inherited from QVariantAnimation
QVariant	currentValue () const
int	duration () const
QEasingCurve	easingCurve () const
QVariant	endValue () const
QVariant	keyValueAt (qreal step) const
	Returns the key frame value for the given step. More...
KeyValues	keyValues () const
	Returns the key frames of this animation. More...
	QVariantAnimation (QObject *parent=0)
	Construct a QVariantAnimation object. More...
void	setDuration (int msecs)
void	setEasingCurve (const QEasingCurve &easing)
void	setEndValue (const QVariant &value)
void	setKeyValueAt (qreal step, const QVariant &value)
	Creates a key frame at the given step with the given value. More...
void	setKeyValues (const KeyValues &values)
	Replaces the current set of key frames with the given keyValues. More...
void	setStartValue (const QVariant &value)
QVariant	startValue () const
	~QVariantAnimation ()
	Destroys the animation. More...
Public Functions inherited from QAbstractAnimation
int	currentLoop () const
int	currentLoopTime () const
	Returns the current time inside the current loop. More...
int	currentTime () const
Direction	direction () const
QAnimationGroup *	group () const
	If this animation is part of a QAnimationGroup, this function returns a pointer to the group; otherwise, it returns 0. More...
int	loopCount () const
	QAbstractAnimation (QObject *parent=0)
	Constructs the QAbstractAnimation base class, and passes parent to QObject's constructor. More...
void	setDirection (Direction direction)
void	setLoopCount (int loopCount)
State	state () const
int	totalDuration () const
	Returns the total and effective duration of the animation, including the loop count. More...
virtual	~QAbstractAnimation ()
	Stops the animation if it's running, then destroys the QAbstractAnimation. More...
Public Functions inherited from QObject
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	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...

Protected Functions
bool	event (QEvent *event)
	Reimplemented Function More...
void	updateCurrentValue (const QVariant &value)
	This virtual function is called by QVariantAnimation whenever the current value changes. More...
void	updateState (QAbstractAnimation::State newState, QAbstractAnimation::State oldState)
	If the startValue is not defined when the state of the animation changes from Stopped to Running, the current property value is used as the initial value for the animation. More...
Protected Functions inherited from QVariantAnimation
bool	event (QEvent *event)
	Reimplemented Function More...
virtual QVariant	interpolated (const QVariant &from, const QVariant &to, qreal progress) const
	This virtual function returns the linear interpolation between variants from and to, at progress, usually a value between 0 and 1. More...
	QVariantAnimation (QVariantAnimationPrivate &dd, QObject *parent=0)
void	updateCurrentTime (int)
	Reimplemented Function More...
void	updateState (QAbstractAnimation::State newState, QAbstractAnimation::State oldState)
	Reimplemented Function More...
Protected Functions inherited from QAbstractAnimation
	QAbstractAnimation (QAbstractAnimationPrivate &dd, QObject *parent=0)
virtual void	updateDirection (QAbstractAnimation::Direction direction)
	This virtual function is called by QAbstractAnimation when the direction of the animation is changed. More...
Protected Functions inherited from QObject
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...

Properties
QByteArray	propertyName
	the target property name for this animation More...
QObject *	targetObject
	the target QObject for this animation. More...

Additional Inherited Members
Public Types inherited from QVariantAnimation
typedef QVariant(*	Interpolator) (const void *from, const void *to, qreal progress)
typedef QPair< qreal, QVariant >	KeyValue
	This is a typedef for QPair<qreal, QVariant>. More...
typedef QVector< KeyValue >	KeyValues
	This is a typedef for QVector<KeyValue> More...
Public Types inherited from QAbstractAnimation
enum	DeletionPolicy { KeepWhenStopped = 0, DeleteWhenStopped }
enum	Direction { Forward, Backward }
	This enum describes the direction of the animation when in Running state. More...
enum	State { Stopped, Paused, Running }
	This enum describes the state of the animation. More...
Public Slots inherited from QAbstractAnimation
void	pause ()
	Pauses the animation. More...
void	resume ()
	Resumes the animation after it was paused. More...
void	setCurrentTime (int msecs)
void	setPaused (bool)
	If paused is true, the animation is paused. More...
void	start (QAbstractAnimation::DeletionPolicy policy=KeepWhenStopped)
	Starts the animation. More...
void	stop ()
	Stops the animation. More...
Public Slots inherited from QObject
void	deleteLater ()
	Schedules this object for deletion. More...
Signals inherited from QVariantAnimation
void	valueChanged (const QVariant &value)
	QVariantAnimation emits this signal whenever the current value changes. More...
Signals inherited from QAbstractAnimation
void	currentLoopChanged (int currentLoop)
	QAbstractAnimation emits this signal whenever the current loop changes. More...
void	directionChanged (QAbstractAnimation::Direction)
	QAbstractAnimation emits this signal whenever the direction has been changed. More...
void	finished ()
	QAbstractAnimation emits this signal after the animation has stopped and has reached the end. More...
void	stateChanged (QAbstractAnimation::State newState, QAbstractAnimation::State oldState)
	QAbstractAnimation emits this signal whenever the state of the animation has changed from oldState to newState. More...
Signals inherited from QObject
void	destroyed (QObject *=0)
	This signal is emitted immediately before the object obj is destroyed, and can not be blocked. More...
Static Public Functions inherited from QObject
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 inherited from QObject
static const QMetaObject	staticMetaObject
	This variable stores the meta-object for the class. More...
Protected Variables inherited from QObject
QScopedPointer< QObjectData >	d_ptr
Static Protected Variables inherited from QObject
static const QMetaObject	staticQtMetaObject
Related Functions inherited from QVariantAnimation
void	qRegisterAnimationInterpolator (QVariant(*func)(const T &from, const T &to, qreal progress))
Related Functions inherited from QObject
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 QPropertyAnimation class animates Qt properties.

Since

4.6

QPropertyAnimation interpolates over Qt's Property System{Qt properties}. As property values are stored in QVariant, the class inherits QVariantAnimation, and supports animation of the same variant types as its super class.

A class declaring properties must be a QObject. To make it possible to animate a property, it must provide a setter (so that QPropertyAnimation can set the property's value). Note that this makes it possible to animate many of Qt's widgets. Let's look at an example:

QPropertyAnimation *animation = new QPropertyAnimation(myWidget, "geometry");
animation->setDuration(10000);
animation->setStartValue(QRect(0, 0, 100, 30));
animation->setEndValue(QRect(250, 250, 100, 30));

animation->start();

The property name and the QObject instance of which property should be animated are passed to the constructor. You can then specify the start and end value of the property. The procedure is equal for properties in classes you have implemented yourself–just check with QVariantAnimation that your QVariant type is supported.

The QVariantAnimation class description explains how to set up the animation in detail. Note, however, that if a start value is not set, the property will start at the value it had when the QPropertyAnimation instance was created.

QPropertyAnimation works like a charm on its own. For complex animations that, for instance, contain several objects, QAnimationGroup is provided. An animation group is an animation that can contain other animations, and that can manage when its animations are played. Look at QParallelAnimationGroup for an example.

See also

QVariantAnimation, QAnimationGroup, {The Animation Framework}

Definition at line 56 of file qpropertyanimation.h.

Constructors and Destructors

QPropertyAnimation() [1/2]

QPropertyAnimation::QPropertyAnimation

(

QObject *

parent = 0

)

Construct a QPropertyAnimation object.

parent is passed to QObject's constructor.

Definition at line 151 of file qpropertyanimation.cpp.

    : QVariantAnimation(*new QPropertyAnimationPrivate, parent)
{
}

QPropertyAnimation() [2/2]

QPropertyAnimation::QPropertyAnimation	(	QObject *	target,
		const QByteArray &	propertyName,
		QObject *	parent = 0
	)

Construct a QPropertyAnimation object.

parent is passed to QObject's constructor. The animation changes the property propertyName on target. The default duration is 250ms.

See also

targetObject, propertyName

Definition at line 163 of file qpropertyanimation.cpp.

    : QVariantAnimation(*new QPropertyAnimationPrivate, parent)
{
    setTargetObject(target);
    setPropertyName(propertyName);
}

~QPropertyAnimation()

QPropertyAnimation::~QPropertyAnimation

(

)

Destroys the QPropertyAnimation instance.

Definition at line 173 of file qpropertyanimation.cpp.

{
    stop();
}

Functions

event()

bool QPropertyAnimation::event ( QEvent *  event )

protectedvirtual

Reimplemented Function

Reimplemented from QAbstractAnimation.

Definition at line 239 of file qpropertyanimation.cpp.

{
    return QVariantAnimation::event(event);
}

propertyName()

QByteArray QPropertyAnimation::propertyName

(

)

const

Referenced by setPropertyName(), and setTargetObject().

setPropertyName()

void QPropertyAnimation::setPropertyName

(

const QByteArray &

propertyName

)

Definition at line 223 of file qpropertyanimation.cpp.

Referenced by QPropertyAnimation().

{
    Q_D(QPropertyAnimation);
    if (d->state != QAbstractAnimation::Stopped) {
        qWarning("QPropertyAnimation::setPropertyName: you can't change the property name of a running animation");
        return;
    }

    d->propertyName = propertyName;
    d->updateMetaProperty();
}

setTargetObject()

void QPropertyAnimation::setTargetObject

(

QObject *

target

)

Definition at line 192 of file qpropertyanimation.cpp.

Referenced by QPropertyAnimation().

{
    Q_D(QPropertyAnimation);
    if (d->targetValue == target)
        return;

    if (d->state != QAbstractAnimation::Stopped) {
        qWarning("QPropertyAnimation::setTargetObject: you can't change the target of a running animation");
        return;
    }

    d->target = d->targetValue = target;
    d->updateMetaProperty();
}

targetObject()

QObject* QPropertyAnimation::targetObject

(

)

const

Referenced by ~QPropertyAnimation().

updateCurrentValue()

void QPropertyAnimation::updateCurrentValue ( const QVariant &  value )

protectedvirtual

This virtual function is called by QVariantAnimation whenever the current value changes.

value is the new, updated value. It updates the current value of the property on the target object.

See also

currentValue, currentTime

Implements QVariantAnimation.

Definition at line 251 of file qpropertyanimation.cpp.

{
    Q_D(QPropertyAnimation);
    d->updateProperty(value);
}

updateState()

void QPropertyAnimation::updateState ( QAbstractAnimation::State  newState, QAbstractAnimation::State  oldState  )

protectedvirtual

If the startValue is not defined when the state of the animation changes from Stopped to Running, the current property value is used as the initial value for the animation.

Reimplemented Function

Reimplemented from QAbstractAnimation.

Definition at line 266 of file qpropertyanimation.cpp.

{
    Q_D(QPropertyAnimation);

    if (!d->target && oldState == Stopped) {
        qWarning("QPropertyAnimation::updateState (%s): Changing state of an animation without target",
                 d->propertyName.constData());
        return;
    }

    QVariantAnimation::updateState(newState, oldState);

    QPropertyAnimation *animToStop = 0;
    {
#ifndef QT_NO_THREAD
        QMutexLocker locker(QMutexPool::globalInstanceGet(&staticMetaObject));
#endif
        typedef QPair<QObject *, QByteArray> QPropertyAnimationPair;
        typedef QHash<QPropertyAnimationPair, QPropertyAnimation*> QPropertyAnimationHash;
        static QPropertyAnimationHash hash;
        //here we need to use value because we need to know to which pointer
        //the animation was referring in case stopped because the target was destroyed
        QPropertyAnimationPair key(d->targetValue, d->propertyName);
        if (newState == Running) {
            d->updateMetaProperty();
            animToStop = hash.value(key, 0);
            hash.insert(key, this);
            // update the default start value
            if (oldState == Stopped) {
                d->setDefaultStartEndValue(d->targetValue->property(d->propertyName.constData()));
                //let's check if we have a start value and an end value
                if (!startValue().isValid() && (d->direction == Backward || !d->defaultStartEndValue.isValid())) {
                    qWarning("QPropertyAnimation::updateState (%s, %s, %s): starting an animation without start value",
                             d->propertyName.constData(), d->target.data()->metaObject()->className(),
                             qPrintable(d->target.data()->objectName()));
                }
                if (!endValue().isValid() && (d->direction == Forward || !d->defaultStartEndValue.isValid())) {
                    qWarning("QPropertyAnimation::updateState (%s, %s, %s): starting an animation without end value",
                             d->propertyName.constData(), d->target.data()->metaObject()->className(),
                             qPrintable(d->target.data()->objectName()));
                }
            }
        } else if (hash.value(key) == this) {
            hash.remove(key);
        }
    }

    //we need to do that after the mutex was unlocked
    if (animToStop) {
        // try to stop the top level group
        QAbstractAnimation *current = animToStop;
        while (current->group() && current->state() != Stopped)
            current = current->group();
        current->stop();
    }
}

Properties

propertyName

QByteArray QPropertyAnimation::propertyName

private

the target property name for this animation

This property defines the target property name for this animation. The property name is required for the animation to operate.

Definition at line 59 of file qpropertyanimation.h.

Referenced by QStateMachinePrivate::initializeAnimation().

targetObject

QObject * QPropertyAnimation::targetObject

private

the target QObject for this animation.

This property defines the target QObject for this animation.

Definition at line 60 of file qpropertyanimation.h.

Referenced by QWidgetAnimator::animationFinished(), and QStateMachinePrivate::initializeAnimation().

---

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

• /src/corelib/animation/qpropertyanimation.h
• /src/corelib/animation/qpropertyanimation.cpp