QBoxLayout Class Reference

The QBoxLayout class lines up child widgets horizontally or vertically. More...

#include <qboxlayout.h>

Inheritance diagram for QBoxLayout:

Public Types
enum	Direction {   LeftToRight, RightToLeft, TopToBottom, BottomToTop,   Down = TopToBottom, Up = BottomToTop }
	This type is used to determine the direction of a box layout. More...
Public Types inherited from QLayout
enum	SizeConstraint {   SetDefaultConstraint, SetNoConstraint, SetMinimumSize, SetFixedSize,   SetMaximumSize, SetMinAndMaxSize }
	The possible values are: More...

Public Functions
void	addItem (QLayoutItem *)
	Reimplemented Function More...
void	addLayout (QLayout *layout, int stretch=0)
	Adds layout to the end of the box, with serial stretch factor stretch. More...
void	addSpacerItem (QSpacerItem *spacerItem)
	Adds spacerItem to the end of this box layout. More...
void	addSpacing (int size)
	Adds a non-stretchable space (a QSpacerItem) with size size to the end of this box layout. More...
void	addStretch (int stretch=0)
	Adds a stretchable space (a QSpacerItem) with zero minimum size and stretch factor stretch to the end of this box layout. More...
void	addStrut (int)
	Limits the perpendicular dimension of the box (e.g. More...
void	addWidget (QWidget *, int stretch=0, Qt::Alignment alignment=0)
	Adds widget to the end of this box layout, with a stretch factor of stretch and alignment alignment. More...
int	count () const
	Reimplemented Function More...
Direction	direction () const
	Returns the direction of the box. More...
Qt::Orientations	expandingDirections () const
	Reimplemented Function More...
bool	hasHeightForWidth () const
	Reimplemented Function More...
int	heightForWidth (int) const
	Reimplemented Function More...
void	insertLayout (int index, QLayout *layout, int stretch=0)
	Inserts layout at position index, with stretch factor stretch. More...
void	insertSpacerItem (int index, QSpacerItem *spacerItem)
	Inserts spacerItem at position index, with zero minimum size and stretch factor. More...
void	insertSpacing (int index, int size)
	Inserts a non-stretchable space (a QSpacerItem) at position index, with size size. More...
void	insertStretch (int index, int stretch=0)
	Inserts a stretchable space (a QSpacerItem) at position index, with zero minimum size and stretch factor stretch. More...
void	insertWidget (int index, QWidget *widget, int stretch=0, Qt::Alignment alignment=0)
	Inserts widget at position index, with stretch factor stretch and alignment alignment. More...
void	invalidate ()
	Resets cached information. More...
QLayoutItem *	itemAt (int) const
	Reimplemented Function More...
QSize	maximumSize () const
	Reimplemented Function More...
int	minimumHeightForWidth (int) const
	Reimplemented Function More...
QSize	minimumSize () const
	Reimplemented Function More...
	QBoxLayout (Direction, QWidget *parent=0)
	Constructs a new QBoxLayout with direction dir and parent widget parent. More...
void	setDirection (Direction)
	Sets the direction of this layout to direction. More...
void	setGeometry (const QRect &)
	Reimplemented Function More...
void	setSpacing (int spacing)
	Reimplements QLayout::setSpacing(). More...
void	setStretch (int index, int stretch)
	Sets the stretch factor at position index. More...
bool	setStretchFactor (QWidget *w, int stretch)
	Sets the stretch factor for widget to stretch and returns true if widget is found in this layout (not including child layouts); otherwise returns false. More...
bool	setStretchFactor (QLayout *l, int stretch)
	Sets the stretch factor for the layout layout to stretch and returns true if layout is found in this layout (not including child layouts); otherwise returns false. More...
QSize	sizeHint () const
	Reimplemented Function More...
int	spacing () const
	Reimplements QLayout::spacing(). More...
int	stretch (int index) const
	Returns the stretch factor at position index. More...
QLayoutItem *	takeAt (int)
	Reimplemented Function More...
	~QBoxLayout ()
	Destroys this box layout. More...
Public Functions inherited from QLayout
bool	activate ()
	Redoes the layout for parentWidget() if necessary. More...
void	addWidget (QWidget *w)
	Adds widget w to this layout in a manner specific to the layout. More...
QMargins	contentsMargins () const
	Returns the margins used around the layout. More...
QRect	contentsRect () const
	Returns the layout's geometry() rectangle, but taking into account the contents margins. More...
Qt::Orientations	expandingDirections () const
	Returns whether this layout can make use of more space than sizeHint(). More...
QRect	geometry () const
	Reimplemented Function More...
void	getContentsMargins (int *left, int *top, int *right, int *bottom) const
virtual int	indexOf (QWidget *) const
	Searches for widget widget in this layout (not including child layouts). More...
void	invalidate ()
	Reimplemented Function More...
bool	isEmpty () const
	Reimplemented Function More...
bool	isEnabled () const
	Returns true if the layout is enabled; otherwise returns false. More...
QLayout *	layout ()
	Reimplemented Function More...
int	margin () const
QSize	maximumSize () const
	Returns the maximum size of this layout. More...
QWidget *	menuBar () const
	Returns the menu bar set for this layout, or 0 if no menu bar is set. More...
QSize	minimumSize () const
	Returns the minimum size of this layout. More...
QWidget *	parentWidget () const
	Returns the parent widget of this layout, or 0 if this layout is not installed on any widget. More...
	QLayout (QWidget *parent)
	Constructs a new top-level QLayout, with parent parent. More...
	QLayout ()
	Constructs a new child QLayout. More...
void	removeItem (QLayoutItem *)
	Removes the layout item item from the layout. More...
void	removeWidget (QWidget *w)
	Removes the widget widget from the layout. More...
bool	setAlignment (QWidget *w, Qt::Alignment alignment)
	Sets the alignment for widget w to alignment and returns true if w is found in this layout (not including child layouts); otherwise returns false. More...
bool	setAlignment (QLayout *l, Qt::Alignment alignment)
	Sets the alignment for the layout l to alignment and returns true if l is found in this layout (not including child layouts); otherwise returns false. More...
void	setContentsMargins (int left, int top, int right, int bottom)
	Sets the left, top, right, and bottom margins to use around the layout. More...
void	setContentsMargins (const QMargins &margins)
	Sets the margins to use around the layout. More...
void	setEnabled (bool)
	Enables this layout if enable is true, otherwise disables it. More...
void	setMargin (int)
void	setMenuBar (QWidget *w)
	Tells the geometry manager to place the menu bar widget at the top of parentWidget(), outside QWidget::contentsMargins(). More...
void	setSizeConstraint (SizeConstraint)
void	setSpacing (int)
SizeConstraint	sizeConstraint () const
int	spacing () const
int	totalHeightForWidth (int w) const
	Also takes contentsMargins and menu bar into account. More...
QSize	totalMaximumSize () const
	Also takes contentsMargins and menu bar into account. More...
QSize	totalMinimumSize () const
	Also takes contentsMargins and menu bar into account. More...
QSize	totalSizeHint () const
	Also takes contentsMargins and menu bar into account. More...
void	update ()
	Updates the layout for parentWidget(). More...
	~QLayout ()
	Destroys the layout, deleting all child layouts. 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	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...
Public Functions inherited from QLayoutItem
Qt::Alignment	alignment () const
	Returns the alignment of this item. More...
QSizePolicy::ControlTypes	controlTypes () const
	Returns the control type(s) for the layout item. More...
	QLayoutItem (Qt::Alignment alignment=0)
	Constructs a layout item with an alignment. More...
void	setAlignment (Qt::Alignment a)
	Sets the alignment of this item to alignment. More...
virtual QSpacerItem *	spacerItem ()
	If this item is a QSpacerItem, it is returned as a QSpacerItem; otherwise 0 is returned. More...
virtual QWidget *	widget ()
	If this item is a QWidget, it is returned as a QWidget; otherwise 0 is returned. More...
virtual	~QLayoutItem ()
	Destroys the QLayoutItem. More...

Protected Functions
void	insertItem (int index, QLayoutItem *)
	Inserts item into this box layout at position index. More...
Protected Functions inherited from QLayout
void	addChildLayout (QLayout *l)
	This function is called from addLayout() or insertLayout() functions in subclasses to add layout l as a sub-layout. More...
void	addChildWidget (QWidget *w)
	This function is called from addWidget() functions in subclasses to add w as a managed widget of a layout. More...
bool	adoptLayout (QLayout *layout)
QRect	alignmentRect (const QRect &) const
	Returns the rectangle that should be covered when the geometry of this layout is set to r, provided that this layout supports setAlignment(). More...
void	childEvent (QChildEvent *e)
	Reimplemented Function More...
	QLayout (QLayoutPrivate &d, QLayout *, QWidget *)
void	widgetEvent (QEvent *)
	Performs child widget layout when the parent widget is resized. More...
Protected Functions inherited from QObject
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...

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	Schedules this object for deletion. 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 QLayout
static QSize	closestAcceptableSize (const QWidget *w, const QSize &s)
	Returns a size that satisfies all size constraints on widget, including heightForWidth() and that is as close as possible to size. 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
Protected Variables inherited from QLayoutItem
Qt::Alignment	align
Static Protected Variables inherited from QObject
static const QMetaObject	staticQtMetaObject
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 QBoxLayout class lines up child widgets horizontally or vertically.

QBoxLayout takes the space it gets (from its parent layout or from the parentWidget()), divides it up into a row of boxes, and makes each managed widget fill one box.

Horizontal box layout with five child widgets

If the QBoxLayout's orientation is Qt::Horizontal the boxes are placed in a row, with suitable sizes. Each widget (or other box) will get at least its minimum size and at most its maximum size. Any excess space is shared according to the stretch factors (more about that below).

Vertical box layout with five child widgets

If the QBoxLayout's orientation is Qt::Vertical, the boxes are placed in a column, again with suitable sizes.

The easiest way to create a QBoxLayout is to use one of the convenience classes, e.g. QHBoxLayout (for Qt::Horizontal boxes) or QVBoxLayout (for Qt::Vertical boxes). You can also use the QBoxLayout constructor directly, specifying its direction as LeftToRight, RightToLeft, TopToBottom, or BottomToTop.

If the QBoxLayout is not the top-level layout (i.e. it is not managing all of the widget's area and children), you must add it to its parent layout before you can do anything with it. The normal way to add a layout is by calling parentLayout->addLayout().

Once you have done this, you can add boxes to the QBoxLayout using one of four functions:

• addWidget() to add a widget to the QBoxLayout and set the widget's stretch factor. (The stretch factor is along the row of boxes.)

• addSpacing() to create an empty box; this is one of the functions you use to create nice and spacious dialogs. See below for ways to set margins.

• addStretch() to create an empty, stretchable box.

• addLayout() to add a box containing another QLayout to the row and set that layout's stretch factor.

Use insertWidget(), insertSpacing(), insertStretch() or insertLayout() to insert a box at a specified position in the layout.

QBoxLayout also includes two margin widths:

• setContentsMargins() sets the width of the outer border on each side of the widget. This is the width of the reserved space along each of the QBoxLayout's four sides.
• setSpacing() sets the width between neighboring boxes. (You can use addSpacing() to get more space at a particular spot.)

The margin default is provided by the style. The default margin most Qt styles specify is 9 for child widgets and 11 for windows. The spacing defaults to the same as the margin width for a top-level layout, or to the same as the parent layout.

To remove a widget from a layout, call removeWidget(). Calling QWidget::hide() on a widget also effectively removes the widget from the layout until QWidget::show() is called.

You will almost always want to use QVBoxLayout and QHBoxLayout rather than QBoxLayout because of their convenient constructors.

See also

QGridLayout, QStackedLayout, {Layout Management}

Definition at line 60 of file qboxlayout.h.

Enumerations

Direction

enum QBoxLayout::Direction

This type is used to determine the direction of a box layout.

• LeftToRight Horizontal from left to right.
• RightToLeft Horizontal from right to left.
• TopToBottom Vertical from top to bottom.
• BottomToTop Vertical from bottom to top.

• Down
• Up

Enumerator
LeftToRight
RightToLeft
TopToBottom
BottomToTop
Down
Up

Definition at line 65 of file qboxlayout.h.

                   { LeftToRight, RightToLeft, TopToBottom, BottomToTop,
                     Down = TopToBottom, Up = BottomToTop };

Constructors and Destructors

QBoxLayout()

QBoxLayout::QBoxLayout ( Direction  dir, QWidget *  parent = 0  )

explicit

Constructs a new QBoxLayout with direction dir and parent widget parent.

See also

direction()

Definition at line 558 of file qboxlayout.cpp.

Referenced by QHBoxLayout::QHBoxLayout(), and QVBoxLayout::QVBoxLayout().

    : QLayout(*new QBoxLayoutPrivate, 0, parent)
{
    Q_D(QBoxLayout);
    d->dir = dir;
}

~QBoxLayout()

QBoxLayout::~QBoxLayout

(

)

Destroys this box layout.

The layout's widgets aren't destroyed.

Definition at line 632 of file qboxlayout.cpp.

{
    Q_D(QBoxLayout);
    d->deleteAll(); // must do it before QObject deletes children, so can't be in ~QBoxLayoutPrivate
}

Functions

addItem()

void QBoxLayout::addItem ( QLayoutItem *  item )

virtual

Reimplemented Function

Implements QLayout.

Definition at line 894 of file qboxlayout.cpp.

Referenced by QCalendarWidgetPrivate::createNavigationBar(), and QScriptDebuggerCodeFinderWidget::QScriptDebuggerCodeFinderWidget().

{
    Q_D(QBoxLayout);
    QBoxLayoutItem *it = new QBoxLayoutItem(item);
    d->list.append(it);
    invalidate();
}

addLayout()

void QBoxLayout::addLayout	(	QLayout *	layout,
		int	stretch = 0
	)

Adds layout to the end of the box, with serial stretch factor stretch.

See also

insertLayout(), addItem(), addWidget()

Definition at line 1140 of file qboxlayout.cpp.

Referenced by QColorDialogPrivate::init(), QPrintPreviewDialogPrivate::init(), QStatusBar::reformat(), and QCoreFuriCuri::timerEvent().

{
    insertLayout(-1, layout, stretch);
}

addSpacerItem()

void QBoxLayout::addSpacerItem

(

QSpacerItem *

spacerItem

)

Adds spacerItem to the end of this box layout.

Since

4.4

See also

addSpacing(), addStretch()

Definition at line 1104 of file qboxlayout.cpp.

{
    insertSpacerItem(-1, spacerItem);
}

addSpacing()

void QBoxLayout::addSpacing

(

int

size

)

Adds a non-stretchable space (a QSpacerItem) with size size to the end of this box layout.

QBoxLayout provides default margin and spacing. This function adds additional space.

See also

insertSpacing(), addItem(), QSpacerItem

Definition at line 1078 of file qboxlayout.cpp.

Referenced by QColorDialogPrivate::init(), QDialogButtonBoxPrivate::layoutButtons(), QComboBoxPrivateContainer::QComboBoxPrivateContainer(), and QStatusBar::reformat().

{
    insertSpacing(-1, size);
}

addStretch()

void QBoxLayout::addStretch

(

int

stretch = 0

)

Adds a stretchable space (a QSpacerItem) with zero minimum size and stretch factor stretch to the end of this box layout.

See also

insertStretch(), addItem(), QSpacerItem

Definition at line 1089 of file qboxlayout.cpp.

Referenced by QColorDialogPrivate::init(), QDialogButtonBoxPrivate::layoutButtons(), and QStatusBar::reformat().

{
    insertStretch(-1, stretch);
}

addStrut()

void QBoxLayout::addStrut

(

int

size

)

Limits the perpendicular dimension of the box (e.g.

height if the box is LeftToRight ) to a minimum of size. Other constraints may increase the limit.

See also

addItem()

Definition at line 1152 of file qboxlayout.cpp.

Referenced by QStatusBar::reformat().

{
    Q_D(QBoxLayout);
    QLayoutItem *b;
    if (horz(d->dir))
        b = QLayoutPrivate::createSpacerItem(this, 0, size, QSizePolicy::Fixed, QSizePolicy::Minimum);
    else
        b = QLayoutPrivate::createSpacerItem(this, size, 0, QSizePolicy::Minimum, QSizePolicy::Fixed);

    QBoxLayoutItem *it = new QBoxLayoutItem(b);
    it->magic = true;
    d->list.append(it);
    invalidate();
}

addWidget()

void QBoxLayout::addWidget	(	QWidget *	widget,
		int	stretch = 0,
		Qt::Alignment	alignment = 0
	)

Adds widget to the end of this box layout, with a stretch factor of stretch and alignment alignment.

The stretch factor applies only in the direction of the QBoxLayout, and is relative to the other boxes and widgets in this QBoxLayout. Widgets and boxes with higher stretch factors grow more.

If the stretch factor is 0 and nothing else in the QBoxLayout has a stretch factor greater than zero, the space is distributed according to the QWidget:sizePolicy() of each widget that's involved.

The alignment is specified by alignment. The default alignment is 0, which means that the widget fills the entire cell.

See also

insertWidget(), addItem(), addLayout(), addStretch(), addSpacing(), addStrut()

Definition at line 1129 of file qboxlayout.cpp.

Referenced by QDialogButtonBoxPrivate::addButtonsToLayout(), QPrintPropertiesDialog::addItemToOptions(), QCalendarTextNavigator::createDateLabel(), QCalendarWidgetPrivate::createNavigationBar(), QInputDialogPrivate::ensureLayout(), QScriptEdit::extraAreaMouseEvent(), QWorkspaceChild::iconWidget(), QColorDialogPrivate::init(), QFontDialogPrivate::init(), QPrintPreviewDialogPrivate::init(), QPrintPreviewWidgetPrivate::init(), QPageSetupDialogPrivate::init(), QDialogButtonBoxPrivate::layoutButtons(), QCalendarWidget::QCalendarWidget(), QComboBoxPrivateContainer::QComboBoxPrivateContainer(), QMessageBoxDetailsText::QMessageBoxDetailsText(), QPageSetupWidget::QPageSetupWidget(), QPrintPropertiesDialog::QPrintPropertiesDialog(), QScriptBreakpointsWidget::QScriptBreakpointsWidget(), QScriptDebuggerCodeFinderWidget::QScriptDebuggerCodeFinderWidget(), QScriptDebuggerCodeView::QScriptDebuggerCodeView(), QScriptDebuggerCodeWidget::QScriptDebuggerCodeWidget(), QScriptDebuggerConsoleWidget::QScriptDebuggerConsoleWidget(), QScriptDebuggerLocalsWidget::QScriptDebuggerLocalsWidget(), QScriptDebuggerScriptsWidget::QScriptDebuggerScriptsWidget(), QScriptDebuggerStackWidget::QScriptDebuggerStackWidget(), QScriptDebugOutputWidget::QScriptDebugOutputWidget(), QScriptErrorLogWidget::QScriptErrorLogWidget(), QScriptNewBreakpointWidget::QScriptNewBreakpointWidget(), QStatusBar::reformat(), QCalendarPopup::setCalendarWidget(), QScriptEngineDebugger::standardWindow(), and QCoreFuriCuri::timerEvent().

{
    insertWidget(-1, widget, stretch, alignment);
}

count()

int QBoxLayout::count ( ) const

virtual

Reimplemented Function

Implements QLayout.

Definition at line 769 of file qboxlayout.cpp.

Referenced by QCalendarWidgetPrivate::createNavigationBar(), QDialogButtonBoxPrivate::layoutButtons(), and QComboBoxPrivateContainer::updateTopBottomMargin().

{
    Q_D(const QBoxLayout);
    return d->list.count();
}

direction()

QBoxLayout::Direction QBoxLayout::direction

(

)

const

Returns the direction of the box.

addWidget() and addSpacing() work in this direction; the stretch stretches in this direction.

See also

QBoxLayout::Direction addWidget() addSpacing()

Definition at line 1308 of file qboxlayout.cpp.

Referenced by setDirection().

{
    Q_D(const QBoxLayout);
    return d->dir;
}

expandingDirections()

Qt::Orientations QBoxLayout::expandingDirections ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Definition at line 811 of file qboxlayout.cpp.

{
    Q_D(const QBoxLayout);
    if (d->dirty)
        const_cast<QBoxLayout*>(this)->d_func()->setupGeom();
    return d->expanding;
}

hasHeightForWidth()

bool QBoxLayout::hasHeightForWidth ( ) const

virtual

Reimplemented Function

Reimplemented from QLayoutItem.

Definition at line 717 of file qboxlayout.cpp.

Referenced by heightForWidth().

{
    Q_D(const QBoxLayout);
    if (d->dirty)
        const_cast<QBoxLayout*>(this)->d_func()->setupGeom();
    return d->hasHfw;
}

heightForWidth()

int QBoxLayout::heightForWidth ( int  w ) const

virtual

Reimplemented Function

Reimplemented from QLayoutItem.

Definition at line 728 of file qboxlayout.cpp.

{
    Q_D(const QBoxLayout);
    if (!hasHeightForWidth())
        return -1;

    int left, top, right, bottom;
    d->effectiveMargins(&left, &top, &right, &bottom);

    w -= left + right;
    if (w != d->hfwWidth)
        const_cast<QBoxLayout*>(this)->d_func()->calcHfw(w);

    return d->hfwHeight + top + bottom;
}

insertItem()

void QBoxLayout::insertItem ( int  index, QLayoutItem *  item  )

protected

Inserts item into this box layout at position index.

If index is negative, the item is added at the end.

See also

addItem(), insertWidget(), insertLayout(), insertStretch(), insertSpacing()

Definition at line 909 of file qboxlayout.cpp.

{
    Q_D(QBoxLayout);
    if (index < 0)                                // append
        index = d->list.count();

    QBoxLayoutItem *it = new QBoxLayoutItem(item);
    d->list.insert(index, it);
    invalidate();
}

insertLayout()

void QBoxLayout::insertLayout	(	int	index,
		QLayout *	layout,
		int	stretch = 0
	)

Inserts layout at position index, with stretch factor stretch.

If index is negative, the layout is added at the end.

layout becomes a child of the box layout.

See also

addLayout(), insertItem()

Definition at line 1010 of file qboxlayout.cpp.

Referenced by addLayout().

{
    Q_D(QBoxLayout);
    if (!adoptLayout(layout))
        return;
    if (index < 0)                                // append
        index = d->list.count();
    QBoxLayoutItem *it = new QBoxLayoutItem(layout, stretch);
    d->list.insert(index, it);
    invalidate();
}

insertSpacerItem()

void QBoxLayout::insertSpacerItem	(	int	index,
		QSpacerItem *	spacerItem
	)

Inserts spacerItem at position index, with zero minimum size and stretch factor.

Since

4.4

If index is negative the space is added at the end.

See also

addSpacerItem(), insertStretch(), insertSpacing()

Definition at line 990 of file qboxlayout.cpp.

Referenced by addSpacerItem().

{
    Q_D(QBoxLayout);
    if (index < 0)                                // append
        index = d->list.count();

    QBoxLayoutItem *it = new QBoxLayoutItem(spacerItem);
    it->magic = true;
    d->list.insert(index, it);
    invalidate();
}

insertSpacing()

void QBoxLayout::insertSpacing	(	int	index,
		int	size
	)

Inserts a non-stretchable space (a QSpacerItem) at position index, with size size.

If index is negative the space is added at the end.

The box layout has default margin and spacing. This function adds additional space.

See also

addSpacing(), insertItem(), QSpacerItem

Definition at line 929 of file qboxlayout.cpp.

Referenced by addSpacing(), and QComboBoxPrivateContainer::QComboBoxPrivateContainer().

{
    Q_D(QBoxLayout);
    if (index < 0)                                // append
        index = d->list.count();

    QLayoutItem *b;
    if (horz(d->dir))
        b = QLayoutPrivate::createSpacerItem(this, size, 0, QSizePolicy::Fixed, QSizePolicy::Minimum);
    else
        b = QLayoutPrivate::createSpacerItem(this, 0, size, QSizePolicy::Minimum, QSizePolicy::Fixed);

    QT_TRY {
        QBoxLayoutItem *it = new QBoxLayoutItem(b);
        it->magic = true;
        d->list.insert(index, it);

    } QT_CATCH(...) {
        delete b;
        QT_RETHROW;
    }
    invalidate();
}

insertStretch()

void QBoxLayout::insertStretch	(	int	index,
		int	stretch = 0
	)

Inserts a stretchable space (a QSpacerItem) at position index, with zero minimum size and stretch factor stretch.

If index is negative the space is added at the end.

See also

addStretch(), insertItem(), QSpacerItem

Definition at line 960 of file qboxlayout.cpp.

Referenced by addStretch(), and QCalendarWidgetPrivate::createNavigationBar().

{
    Q_D(QBoxLayout);
    if (index < 0)                                // append
        index = d->list.count();

    QLayoutItem *b;
    if (horz(d->dir))
        b = QLayoutPrivate::createSpacerItem(this, 0, 0, QSizePolicy::Expanding, QSizePolicy::Minimum);
    else
        b = QLayoutPrivate::createSpacerItem(this, 0, 0, QSizePolicy::Minimum, QSizePolicy::Expanding);

    QBoxLayoutItem *it = new QBoxLayoutItem(b, stretch);
    it->magic = true;
    d->list.insert(index, it);
    invalidate();
}

insertWidget()

void QBoxLayout::insertWidget	(	int	index,
		QWidget *	widget,
		int	stretch = 0,
		Qt::Alignment	alignment = 0
	)

Inserts widget at position index, with stretch factor stretch and alignment alignment.

If index is negative, the widget is added at the end.

The stretch factor applies only in the direction of the QBoxLayout, and is relative to the other boxes and widgets in this QBoxLayout. Widgets and boxes with higher stretch factors grow more.

If the stretch factor is 0 and nothing else in the QBoxLayout has a stretch factor greater than zero, the space is distributed according to the QWidget:sizePolicy() of each widget that's involved.

The alignment is specified by alignment. The default alignment is 0, which means that the widget fills the entire cell.

See also

addWidget(), insertItem()

Definition at line 1042 of file qboxlayout.cpp.

Referenced by addWidget(), QComboBoxPrivateContainer::QComboBoxPrivateContainer(), QAbstractScrollAreaPrivate::replaceScrollBar(), and QInputDialogPrivate::setInputWidget().

{
    Q_D(QBoxLayout);
    if (!checkWidget(this, widget))
         return;
    addChildWidget(widget);
    if (index < 0)                                // append
        index = d->list.count();
    QWidgetItem *b = QLayoutPrivate::createWidgetItem(this, widget);
    b->setAlignment(alignment);

    QBoxLayoutItem *it;
    QT_TRY{
        it = new QBoxLayoutItem(b, stretch);
    } QT_CATCH(...) {
        delete b;
        QT_RETHROW;
    }

    QT_TRY{
        d->list.insert(index, it);
    } QT_CATCH(...) {
        delete it;
        QT_RETHROW;
    }
    invalidate();
}

invalidate()

void QBoxLayout::invalidate ( )

virtual

Resets cached information.

Reimplemented from QLayoutItem.

Definition at line 759 of file qboxlayout.cpp.

Referenced by addItem(), addStrut(), insertItem(), insertLayout(), insertSpacerItem(), insertSpacing(), insertStretch(), insertWidget(), setDirection(), setSpacing(), setStretch(), setStretchFactor(), takeAt(), and QComboBoxPrivateContainer::updateTopBottomMargin().

{
    Q_D(QBoxLayout);
    d->setDirty();
    QLayout::invalidate();
}

itemAt()

QLayoutItem * QBoxLayout::itemAt ( int  index ) const

virtual

Reimplemented Function

Implements QLayout.

Definition at line 778 of file qboxlayout.cpp.

Referenced by QDialogButtonBoxPrivate::layoutButtons(), and QComboBoxPrivateContainer::updateTopBottomMargin().

{
    Q_D(const QBoxLayout);
    return index >= 0 && index < d->list.count() ? d->list.at(index)->item : 0;
}

maximumSize()

QSize QBoxLayout::maximumSize ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Definition at line 699 of file qboxlayout.cpp.

{
    Q_D(const QBoxLayout);
    if (d->dirty)
        const_cast<QBoxLayout*>(this)->d_func()->setupGeom();

    QSize s = d->maxSize.boundedTo(QSize(QLAYOUTSIZE_MAX, QLAYOUTSIZE_MAX));

    if (alignment() & Qt::AlignHorizontal_Mask)
        s.setWidth(QLAYOUTSIZE_MAX);
    if (alignment() & Qt::AlignVertical_Mask)
        s.setHeight(QLAYOUTSIZE_MAX);
    return s;
}

minimumHeightForWidth()

int QBoxLayout::minimumHeightForWidth ( int  w ) const

virtual

Reimplemented Function

Reimplemented from QLayoutItem.

Definition at line 747 of file qboxlayout.cpp.

{
    Q_D(const QBoxLayout);
    (void) heightForWidth(w);
    int top, bottom;
    d->effectiveMargins(0, &top, 0, &bottom);
    return d->hasHfw ? (d->hfwMinHeight + top + bottom) : -1;
}

minimumSize()

QSize QBoxLayout::minimumSize ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Definition at line 688 of file qboxlayout.cpp.

{
    Q_D(const QBoxLayout);
    if (d->dirty)
        const_cast<QBoxLayout*>(this)->d_func()->setupGeom();
    return d->minSize;
}

setDirection()

void QBoxLayout::setDirection

(

Direction

direction

)

Sets the direction of this layout to direction.

Definition at line 1257 of file qboxlayout.cpp.

{
    Q_D(QBoxLayout);
    if (d->dir == direction)
        return;
    if (horz(d->dir) != horz(direction)) {
        //swap around the spacers (the "magic" bits)
        //#### a bit yucky, knows too much.
        //#### probably best to add access functions to spacerItem
        //#### or even a QSpacerItem::flip()
        for (int i = 0; i < d->list.size(); ++i) {
            QBoxLayoutItem *box = d->list.at(i);
            if (box->magic) {
                QSpacerItem *sp = box->item->spacerItem();
                if (sp) {
                    if (sp->expandingDirections() == Qt::Orientations(0) /*No Direction*/) {
                        //spacing or strut
                        QSize s = sp->sizeHint();
                        sp->changeSize(s.height(), s.width(),
                            horz(direction) ? QSizePolicy::Fixed:QSizePolicy::Minimum,
                            horz(direction) ? QSizePolicy::Minimum:QSizePolicy::Fixed);

                    } else {
                        //stretch
                        if (horz(direction))
                            sp->changeSize(0, 0, QSizePolicy::Expanding,
                                            QSizePolicy::Minimum);
                        else
                            sp->changeSize(0, 0, QSizePolicy::Minimum,
                                            QSizePolicy::Expanding);
                    }
                }
            }
        }
    }
    d->dir = direction;
    invalidate();
}

setGeometry()

void QBoxLayout::setGeometry ( const QRect &  r )

virtual

Reimplemented Function

Reimplemented from QLayout.

Definition at line 822 of file qboxlayout.cpp.

{
    Q_D(QBoxLayout);
    if (d->dirty || r != geometry()) {
        QRect oldRect = geometry();
        QLayout::setGeometry(r);
        if (d->dirty)
            d->setupGeom();
        QRect cr = alignment() ? alignmentRect(r) : r;

        int left, top, right, bottom;
        d->effectiveMargins(&left, &top, &right, &bottom);
        QRect s(cr.x() + left, cr.y() + top,
                cr.width() - (left + right),
                cr.height() - (top + bottom));

        QVector<QLayoutStruct> a = d->geomArray;
        int pos = horz(d->dir) ? s.x() : s.y();
        int space = horz(d->dir) ? s.width() : s.height();
        int n = a.count();
        if (d->hasHfw && !horz(d->dir)) {
            for (int i = 0; i < n; i++) {
                QBoxLayoutItem *box = d->list.at(i);
                if (box->item->hasHeightForWidth()) {
                    int width = qBound(box->item->minimumSize().width(), s.width(), box->item->maximumSize().width());
                    a[i].sizeHint = a[i].minimumSize =
                                    box->item->heightForWidth(width);
                }
            }
        }

        Direction visualDir = d->dir;
        QWidget *parent = parentWidget();
        if (parent && parent->isRightToLeft()) {
            if (d->dir == LeftToRight)
                visualDir = RightToLeft;
            else if (d->dir == RightToLeft)
                visualDir = LeftToRight;
        }

        qGeomCalc(a, 0, n, pos, space);

        bool reverse = (horz(visualDir)
                        ? ((r.right() > oldRect.right()) != (visualDir == RightToLeft))
                        : r.bottom() > oldRect.bottom());
        for (int j = 0; j < n; j++) {
            int i = reverse ? n-j-1 : j;
            QBoxLayoutItem *box = d->list.at(i);

            switch (visualDir) {
            case LeftToRight:
                box->item->setGeometry(QRect(a.at(i).pos, s.y(), a.at(i).size, s.height()));
                break;
            case RightToLeft:
                box->item->setGeometry(QRect(s.left() + s.right() - a.at(i).pos - a.at(i).size + 1,
                                             s.y(), a.at(i).size, s.height()));
                break;
            case TopToBottom:
                box->item->setGeometry(QRect(s.x(), a.at(i).pos, s.width(), a.at(i).size));
                break;
            case BottomToTop:
                box->item->setGeometry(QRect(s.x(),
                                             s.top() + s.bottom() - a.at(i).pos - a.at(i).size + 1,
                                             s.width(), a.at(i).size));
            }
        }
    }
}

setSpacing()

void QBoxLayout::setSpacing

(

int

spacing

)

Reimplements QLayout::setSpacing().

Sets the spacing property to spacing.

See also

QLayout::setSpacing(), spacing()

Definition at line 667 of file qboxlayout.cpp.

Referenced by QCalendarWidgetPrivate::createNavigationBar(), QBoxLayout(), QCalendarWidget::QCalendarWidget(), QComboBoxPrivateContainer::QComboBoxPrivateContainer(), QHBoxLayout::QHBoxLayout(), QScriptDebuggerCodeFinderWidget::QScriptDebuggerCodeFinderWidget(), QScriptDebuggerConsoleWidget::QScriptDebuggerConsoleWidget(), QScriptDebugOutputWidget::QScriptDebugOutputWidget(), QScriptErrorLogWidget::QScriptErrorLogWidget(), QScriptNewBreakpointWidget::QScriptNewBreakpointWidget(), QVBoxLayout::QVBoxLayout(), QStatusBar::reformat(), and QCalendarPopup::setCalendarWidget().

{
    Q_D(QBoxLayout);
    d->spacing = spacing;
    invalidate();
}

setStretch()

void QBoxLayout::setStretch	(	int	index,
		int	stretch
	)

Sets the stretch factor at position index.

to stretch.

Since

4.5

Definition at line 1228 of file qboxlayout.cpp.

{
    Q_D(QBoxLayout);
    if (index >= 0 && index < d->list.size()) {
        QBoxLayoutItem *box = d->list.at(index);
        if (box->stretch != stretch) {
            box->stretch = stretch;
            invalidate();
        }
    }
}

setStretchFactor() [1/2]

bool QBoxLayout::setStretchFactor	(	QWidget *	widget,
		int	stretch
	)

Sets the stretch factor for widget to stretch and returns true if widget is found in this layout (not including child layouts); otherwise returns false.

See also

setAlignment()

Definition at line 1180 of file qboxlayout.cpp.

{
    Q_D(QBoxLayout);
    if (!widget)
        return false;
    for (int i = 0; i < d->list.size(); ++i) {
        QBoxLayoutItem *box = d->list.at(i);
        if (box->item->widget() == widget) {
            box->stretch = stretch;
            invalidate();
            return true;
        }
    }
    return false;
}

setStretchFactor() [2/2]

bool QBoxLayout::setStretchFactor	(	QLayout *	layout,
		int	stretch
	)

Sets the stretch factor for the layout layout to stretch and returns true if layout is found in this layout (not including child layouts); otherwise returns false.

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Definition at line 1206 of file qboxlayout.cpp.

{
    Q_D(QBoxLayout);
    for (int i = 0; i < d->list.size(); ++i) {
        QBoxLayoutItem *box = d->list.at(i);
        if (box->item->layout() == layout) {
            if (box->stretch != stretch) {
                box->stretch = stretch;
                invalidate();
            }
            return true;
        }
    }
    return false;
}

sizeHint()

QSize QBoxLayout::sizeHint ( ) const

virtual

Reimplemented Function

Implements QLayoutItem.

Definition at line 677 of file qboxlayout.cpp.

{
    Q_D(const QBoxLayout);
    if (d->dirty)
        const_cast<QBoxLayout*>(this)->d_func()->setupGeom();
    return d->sizeHint;
}

spacing()

int QBoxLayout::spacing

(

)

const

Reimplements QLayout::spacing().

If the spacing property is valid, that value is returned. Otherwise, a value for the spacing property is computed and returned. Since layout spacing in a widget is style dependent, if the parent is a widget, it queries the style for the (horizontal or vertical) spacing of the layout. Otherwise, the parent is a layout, and it queries the parent layout for the spacing().

See also

QLayout::spacing(), setSpacing()

Definition at line 649 of file qboxlayout.cpp.

Referenced by QColorDialogPrivate::init(), QBoxLayout(), QHBoxLayout::QHBoxLayout(), QVBoxLayout::QVBoxLayout(), and setSpacing().

{
    Q_D(const QBoxLayout);
    if (d->spacing >=0) {
        return d->spacing;
    } else {
        return qSmartSpacing(this, d->dir == LeftToRight || d->dir == RightToLeft
                                           ? QStyle::PM_LayoutHorizontalSpacing
                                           : QStyle::PM_LayoutVerticalSpacing);
    }
}

stretch()

int QBoxLayout::stretch

(

int

index

)

const

Returns the stretch factor at position index.

Since

4.5

Definition at line 1246 of file qboxlayout.cpp.

Referenced by setStretch(), and setStretchFactor().

{
    Q_D(const QBoxLayout);
    if (index >= 0 && index < d->list.size())
        return d->list.at(index)->stretch;
    return -1;
}

takeAt()

QLayoutItem * QBoxLayout::takeAt ( int  index )

virtual

Reimplemented Function

Implements QLayout.

Definition at line 787 of file qboxlayout.cpp.

Referenced by QDialogButtonBoxPrivate::layoutButtons().

{
    Q_D(QBoxLayout);
    if (index < 0 || index >= d->list.count())
        return 0;
    QBoxLayoutItem *b = d->list.takeAt(index);
    QLayoutItem *item = b->item;
    b->item = 0;
    delete b;

    if (QLayout *l = item->layout()) {
        // sanity check in case the user passed something weird to QObject::setParent()
        if (l->parent() == this)
            l->setParent(0);
    }

    invalidate();
    return item;
}

---

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

• /src/gui/kernel/qboxlayout.h
• /src/gui/kernel/qboxlayout.cpp