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

#include <qboxlayout.h>

Inheritance diagram for QBoxLayout:

Collaboration 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 Member Functions
	QBoxLayout (Direction, QWidget *parent=nullptr)
	Constructs a new QBoxLayout with direction dir and parent widget parent.

	~QBoxLayout ()
	Destroys this box layout.

Direction	direction () const
	Returns the direction of the box.

void	setDirection (Direction)
	Sets the direction of this layout to direction.

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

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.

void	addSpacerItem (QSpacerItem *spacerItem)

void	addWidget (QWidget *, int stretch=0, Qt::Alignment alignment=Qt::Alignment())
	Adds widget to the end of this box layout, with a stretch factor of stretch and alignment alignment.

void	addLayout (QLayout *layout, int stretch=0)
	Adds layout to the end of the box, with serial stretch factor stretch.

void	addStrut (int)
	Limits the perpendicular dimension of the box (e.g.

void	addItem (QLayoutItem *) override
	\reimp

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

void	insertStretch (int index, int stretch=0)
	Inserts a stretchable space (a QSpacerItem) at position index, with zero minimum size and stretch factor stretch.

void	insertSpacerItem (int index, QSpacerItem *spacerItem)

void	insertWidget (int index, QWidget *widget, int stretch=0, Qt::Alignment alignment=Qt::Alignment())
	Inserts widget at position index, with stretch factor stretch and alignment alignment.

void	insertLayout (int index, QLayout *layout, int stretch=0)
	Inserts layout at position index, with stretch factor stretch.

void	insertItem (int index, QLayoutItem *)
	Inserts item into this box layout at position index.

int	spacing () const override
	Reimplements QLayout::spacing().

void	setSpacing (int spacing) override
	Reimplements QLayout::setSpacing().

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`.

bool	setStretchFactor (QLayout *l, int stretch)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.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`.

void	setStretch (int index, int stretch)
	Sets the stretch factor at position index.

int	stretch (int index) const
	Returns the stretch factor at position index.

QSize	sizeHint () const override
	\reimp

QSize	minimumSize () const override
	\reimp

QSize	maximumSize () const override
	\reimp

bool	hasHeightForWidth () const override
	\reimp

int	heightForWidth (int) const override
	\reimp

int	minimumHeightForWidth (int) const override
	\reimp

Qt::Orientations	expandingDirections () const override
	\reimp

void	invalidate () override
	Resets cached information.

QLayoutItem *	itemAt (int) const override
	\reimp

QLayoutItem *	takeAt (int) override
	\reimp

int	count () const override
	\reimp

void	setGeometry (const QRect &) override
	\reimp

Public Member Functions inherited from QLayout
	QLayout (QWidget *parent=nullptr)
	Constructs a new top-level QLayout, with parent parent.

	~QLayout ()

virtual int	spacing () const

virtual void	setSpacing (int)

void	setContentsMargins (int left, int top, int right, int bottom)

void	setContentsMargins (const QMargins &margins)

void	unsetContentsMargins ()

void	getContentsMargins (int left, int top, int right, int bottom) const

QMargins	contentsMargins () const

QRect	contentsRect () const

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`.

bool	setAlignment (QLayout *l, Qt::Alignment alignment)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.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`.

void	setSizeConstraint (SizeConstraint)

SizeConstraint	sizeConstraint () const

void	setMenuBar (QWidget *w)
	Tells the geometry manager to place the menu bar widget at the top of parentWidget(), outside QWidget::contentsMargins().

QWidget *	menuBar () const
	Returns the menu bar set for this layout, or \nullptr if no menu bar is set.

QWidget *	parentWidget () const
	Returns the parent widget of this layout, or \nullptr if this layout is not installed on any widget.

void	invalidate () override
	\reimp

QRect	geometry () const override
	\reimp

bool	activate ()
	Redoes the layout for parentWidget() if necessary.

void	update ()
	Updates the layout for parentWidget().

void	addWidget (QWidget *w)
	Adds widget w to this layout in a manner specific to the layout.

virtual void	addItem (QLayoutItem *)=0
	Implemented in subclasses to add an item.

void	removeWidget (QWidget *w)
	Removes the widget widget from the layout.

void	removeItem (QLayoutItem *)
	Removes the layout item item from the layout.

Qt::Orientations	expandingDirections () const override
	Returns whether this layout can make use of more space than sizeHint().

QSize	minimumSize () const override
	Returns the minimum size of this layout.

QSize	maximumSize () const override
	Returns the maximum size of this layout.

virtual void	setGeometry (const QRect &) override
	\reimp

virtual QLayoutItem *	itemAt (int index) const =0
	Must be implemented in subclasses to return the layout item at index.

virtual QLayoutItem *	takeAt (int index)=0
	Must be implemented in subclasses to remove the layout item at index from the layout, and return the item.

virtual int	indexOf (const QWidget *) const
	Searches for widget widget in this layout (not including child layouts).

virtual int	indexOf (const QLayoutItem *) const

virtual int	count () const =0
	Must be implemented in subclasses to return the number of items in the layout.

bool	isEmpty () const override
	\reimp

QSizePolicy::ControlTypes	controlTypes () const override
	\reimp

virtual QLayoutItem *	replaceWidget (QWidget from, QWidget to, Qt::FindChildOptions options=Qt::FindChildrenRecursively)

int	totalMinimumHeightForWidth (int w) const

int	totalHeightForWidth (int w) const

QSize	totalMinimumSize () const

QSize	totalMaximumSize () const

QSize	totalSizeHint () const

QLayout *	layout () override
	\reimp

void	setEnabled (bool)
	Enables this layout if enable is true, otherwise disables it.

bool	isEnabled () const
	Returns `true` if the layout is enabled; otherwise returns `false`.

void	setAlignment (Qt::Alignment a)
	Sets the alignment of this item to alignment.

Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)
	Constructs an object with parent object parent.

virtual	~QObject ()
	Destroys the object, deleting all its child objects.

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

virtual bool	eventFilter (QObject watched, QEvent event)
	Filters events if this object has been installed as an event filter for the watched object.

QString	objectName () const

Q_WEAK_OVERLOAD void	setObjectName (const QString &name)
	Sets the object's name to name.

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

QBindable< QString >	bindableObjectName ()

bool	isWidgetType () const
	Returns `true` if the object is a widget; otherwise returns `false`.

bool	isWindowType () const
	Returns `true` if the object is a window; otherwise returns `false`.

bool	isQuickItemType () const
	Returns `true` if the object is a QQuickItem; otherwise returns `false`.

bool	signalsBlocked () const noexcept
	Returns `true` if signals are blocked; otherwise returns `false`.

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

QThread *	thread () const
	Returns the thread in which the object lives.

void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children.

int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
	This is an overloaded function that will start a timer of type timerType and a timeout of interval milliseconds.

int	startTimer (std::chrono::milliseconds time, Qt::TimerType timerType=Qt::CoarseTimer)

void	killTimer (int id)
	Kills the timer with timer identifier, id.

template<typename T >
T	findChild (const QString &aName=QString(), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns the child of this object that can be cast into type T and that is called name, or \nullptr if there is no such object.

template<typename T >
QList< T >	findChildren (const QString &aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) 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.

template<typename T >
QList< T >	findChildren (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

const QObjectList &	children () const
	Returns a list of child objects.

void	setParent (QObject *parent)
	Makes the object a child of parent.

void	installEventFilter (QObject *filterObj)
	Installs an event filter filterObj on this object.

void	removeEventFilter (QObject *obj)
	Removes an event filter object obj from this object.

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

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

bool	disconnect (const QObject receiver, const char member=nullptr) const

void	dumpObjectTree () const
	Dumps a tree of children to the debug output.

void	dumpObjectInfo () const
	Dumps information about signal connections, etc.

bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value.

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

QVariant	property (const char *name) const
	Returns the value of the object's name property.

QList< QByteArray >	dynamicPropertyNames () const

QBindingStorage *	bindingStorage ()

const QBindingStorage *	bindingStorage () const

QObject *	parent () const
	Returns a pointer to the parent object.

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`.

Public Member Functions inherited from QLayoutItem
	QLayoutItem (Qt::Alignment alignment=Qt::Alignment())
	Constructs a layout item with an alignment.

virtual	~QLayoutItem ()
	Destroys the QLayoutItem.

virtual QSize	sizeHint () const =0
	Implemented in subclasses to return the preferred size of this item.

virtual QSize	minimumSize () const =0
	Implemented in subclasses to return the minimum size of this item.

virtual QSize	maximumSize () const =0
	Implemented in subclasses to return the maximum size of this item.

virtual Qt::Orientations	expandingDirections () const =0
	Returns whether this layout item can make use of more space than sizeHint().

virtual void	setGeometry (const QRect &)=0
	Implemented in subclasses to set this item's geometry to r.

virtual QRect	geometry () const =0
	Returns the rectangle covered by this layout item.

virtual bool	isEmpty () const =0
	Implemented in subclasses to return whether this item is empty, i.e.

virtual bool	hasHeightForWidth () const
	Returns `true` if this layout's preferred height depends on its width; otherwise returns `false`.

virtual int	heightForWidth (int) const
	Returns the preferred height for this layout item, given the width, which is not used in this default implementation.

virtual int	minimumHeightForWidth (int) const
	Returns the minimum height this widget needs for the given width, w.

virtual void	invalidate ()
	Invalidates any cached information in this layout item.

virtual QWidget *	widget () const
	If this item manages a QWidget, returns that widget.

virtual QLayout *	layout ()
	If this item is a QLayout, it is returned as a QLayout; otherwise \nullptr is returned.

virtual QSpacerItem *	spacerItem ()
	If this item is a QSpacerItem, it is returned as a QSpacerItem; otherwise \nullptr is returned.

Qt::Alignment	alignment () const
	Returns the alignment of this item.

void	setAlignment (Qt::Alignment a)
	Sets the alignment of this item to alignment.

virtual QSizePolicy::ControlTypes	controlTypes () const
	Returns the control type(s) for the layout item.

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe

Signals inherited from QObject
void	destroyed (QObject *=nullptr)
	This signal is emitted immediately before the object obj is destroyed, after any instances of QPointer have been notified, and cannot be blocked.

void	objectNameChanged (const QString &objectName, QPrivateSignal)
	This signal is emitted after the object's name has been changed.

Static Public Member 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.

Static Public Member Functions inherited from QObject
static QMetaObject::Connection	connect (const QObject sender, const char signal, const QObject receiver, const char member, Qt::ConnectionType=Qt::AutoConnection)
	\threadsafe

static QMetaObject::Connection	connect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::ContextTypeForFunctor< Func2 >::ContextType context, Func2 &&slot, Qt::ConnectionType type=Qt::AutoConnection)

template<typename Func1 , typename Func2 >
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 &&slot)

static bool	disconnect (const QObject sender, const char signal, const QObject receiver, const char member)
	\threadsafe

static bool	disconnect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &member)

static bool	disconnect (const QMetaObject::Connection &)
	Disconnect a connection.

template<typename Func1 , typename Func2 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::FunctionPointer< Func2 >::Object receiver, Func2 slot)

template<typename Func1 >
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const QObject receiver, void **zero)

Protected Member Functions inherited from QLayout
void	widgetEvent (QEvent *)

void	childEvent (QChildEvent *e) override
	\reimp

void	addChildLayout (QLayout *l)
	This function is called from `addLayout()` or `insertLayout()` functions in subclasses to add layout childLayout as a sub-layout.

void	addChildWidget (QWidget *w)
	This function is called from `addWidget()` functions in subclasses to add w as a managed widget of a layout.

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().

	QLayout (QLayoutPrivate &d, QLayout , QWidget )

Protected Member Functions inherited from QObject
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 \nullptr.

int	senderSignalIndex () const

int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal.

bool	isSignalConnected (const QMetaMethod &signal) const

virtual void	timerEvent (QTimerEvent *event)
	This event handler can be reimplemented in a subclass to receive timer events for the object.

virtual void	childEvent (QChildEvent *event)
	This event handler can be reimplemented in a subclass to receive child events.

virtual void	customEvent (QEvent *event)
	This event handler can be reimplemented in a subclass to receive custom events.

virtual void	connectNotify (const QMetaMethod &signal)

virtual void	disconnectNotify (const QMetaMethod &signal)

	QObject (QObjectPrivate &dd, QObject *parent=nullptr)

Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr

Protected Attributes inherited from QLayoutItem
Qt::Alignment	align

Properties inherited from QLayout
int	spacing
	the spacing between widgets inside the layout

QMargins	contentsMargins

SizeConstraint	sizeConstraint
	the resize mode of the layout

Properties inherited from QObject
QString	objectName
	the name of this object

Related Symbols inherited from QObject
template< class T > T	qobject_cast (const QObject *object)
	Returns the given object cast to type T if the object is of type T (or of a subclass); otherwise returns \nullptr.

template< typename T > T	qFindChildqFindChildren (const QObject *obj, const QString &name)()

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

	QObjectList
	\macro Q_CLASSINFO(Name, Value)

Detailed Description

The QBoxLayout class lines up child widgets horizontally or vertically.

\inmodule QtWidgets

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:

\list

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. \endlist

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

QBoxLayout also includes two margin widths:

\list

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.) \endlist

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 20 of file qboxlayout.h.

Member Enumeration Documentation

◆ Direction

enum QBoxLayout::Direction

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

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

\omitvalue Down \omitvalue Up

Enumerator
LeftToRight
RightToLeft
TopToBottom
BottomToTop
Down
Up

Definition at line 25 of file qboxlayout.h.

Constructor & Destructor Documentation

◆ QBoxLayout()

QBoxLayout::QBoxLayout	(	Direction	dir,
		QWidget *	parent = `nullptr`
	)

explicit

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

The layout is set directly as the top-level layout for parent. There can be only one top-level layout for a widget. It is returned by QWidget::layout().

See also: direction(), QWidget::setLayout()

Definition at line 529 of file qboxlayout.cpp.

References d, and dir.

◆ ~QBoxLayout()

QBoxLayout::~QBoxLayout ( )

Destroys this box layout.

The layout's widgets aren't destroyed.

Definition at line 543 of file qboxlayout.cpp.

References d.

Member Function Documentation

◆ addItem()

void QBoxLayout::addItem ( QLayoutItem * item )

overridevirtual

\reimp

Implements QLayout.

Definition at line 805 of file qboxlayout.cpp.

References d, invalidate(), it, and item.

Referenced by QCalendarWidgetPrivate::createNavigationBar(), and QWizardPrivate::init().

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◆ 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 1019 of file qboxlayout.cpp.

References insertLayout(), QLayout::layout(), and stretch().

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

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◆ addSpacerItem()

void QBoxLayout::addSpacerItem ( QSpacerItem * spacerItem )

Since: 4.4

Adds spacerItem to the end of this box layout.

See also: addSpacing(), addStretch()

Definition at line 983 of file qboxlayout.cpp.

References insertSpacerItem(), and QLayoutItem::spacerItem().

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◆ 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 960 of file qboxlayout.cpp.

References insertSpacing().

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

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◆ 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 971 of file qboxlayout.cpp.

References insertStretch(), and stretch().

Referenced by ClipWindow::ClipWindow(), QColorDialogPrivate::initWidgets(), QDialogButtonBoxPrivate::layoutButtons(), main(), QStatusBar::reformat(), and QWizardPrivate::setButtonLayout().

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◆ addStrut()

void QBoxLayout::addStrut ( int size )

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

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

See also: addItem()

Definition at line 1031 of file qboxlayout.cpp.

References QLayoutPrivate::createSpacerItem(), d, QSizePolicy::Fixed, horz(), invalidate(), it, and QSizePolicy::Minimum.

Referenced by QStatusBar::reformat().

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◆ addWidget()

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

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 \l{direction()}{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 1008 of file qboxlayout.cpp.

References QLayoutItem::alignment(), insertWidget(), stretch(), and QLayoutItem::widget().

Referenced by ClipWindow::ClipWindow(), MainWindow::MainWindow(), QPageSetupWidget::QPageSetupWidget(), QPrintPropertiesDialog::QPrintPropertiesDialog(), QWatermarkLabel::QWatermarkLabel(), QDialogButtonBoxPrivate::addButtonsToLayout(), QCalendarWidgetPrivate::createNavigationBar(), QInputDialogPrivate::ensureLayout(), extension(), QUnixPageSetupDialogPrivate::init(), QPrintDialogPrivate::init(), QFontDialogPrivate::init(), QPrintPreviewDialogPrivate::init(), QColorDialogPrivate::initWidgets(), QDialogButtonBoxPrivate::layoutButtons(), main(), main(), QStatusBar::reformat(), QToolBoxPrivate::relayout(), QWizardPrivate::setButtonLayout(), QCalendarPopup::setCalendarWidget(), and QWatermarkLabel::setSideWidget().

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◆ count()

int QBoxLayout::count ( ) const

overridevirtual

\reimp

Implements QLayout.

Definition at line 680 of file qboxlayout.cpp.

References d.

Referenced by QGraphicsLayoutPrivate::activateRecursive(), QCalendarWidgetPrivate::createNavigationBar(), hideOrShowWidgetsInLayout(), QDialogButtonBoxPrivate::layoutButtons(), paintLayout(), QWizardPrivate::setButtonLayout(), QWizardPrivate::updateLayout(), and QComboBoxPrivateContainer::updateTopBottomMargin().

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◆ 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 1175 of file qboxlayout.cpp.

References d.

Referenced by setDirection().

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◆ expandingDirections()

Qt::Orientations QBoxLayout::expandingDirections ( ) const

overridevirtual

\reimp

Implements QLayoutItem.

Definition at line 722 of file qboxlayout.cpp.

References d.

◆ hasHeightForWidth()

bool QBoxLayout::hasHeightForWidth ( ) const

overridevirtual

\reimp

Reimplemented from QLayoutItem.

Definition at line 628 of file qboxlayout.cpp.

References d.

Referenced by heightForWidth().

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◆ heightForWidth()

int QBoxLayout::heightForWidth ( int w ) const

overridevirtual

\reimp

Reimplemented from QLayoutItem.

Definition at line 639 of file qboxlayout.cpp.

References d, and hasHeightForWidth().

Referenced by minimumHeightForWidth().

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◆ insertItem()

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

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 820 of file qboxlayout.cpp.

References d, invalidate(), it, and item.

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◆ 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 904 of file qboxlayout.cpp.

References QLayout::adoptLayout(), d, invalidate(), it, QLayout::layout(), and stretch().

Referenced by addLayout().

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◆ insertSpacerItem()

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

Since: 4.4

Inserts spacerItem at position index, with zero minimum size and stretch factor. If index is negative the space is added at the end.

See also: addSpacerItem(), insertStretch(), insertSpacing()

Definition at line 886 of file qboxlayout.cpp.

References d, invalidate(), it, and QLayoutItem::spacerItem().

Referenced by addSpacerItem().

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◆ 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 838 of file qboxlayout.cpp.

References QLayoutPrivate::createSpacerItem(), d, QSizePolicy::Fixed, horz(), invalidate(), it, and QSizePolicy::Minimum.

Referenced by addSpacing().

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◆ 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 861 of file qboxlayout.cpp.

References QLayoutPrivate::createSpacerItem(), d, QSizePolicy::Expanding, horz(), invalidate(), it, QSizePolicy::Minimum, and stretch().

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

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◆ insertWidget()

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

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 \l{direction()}{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 937 of file qboxlayout.cpp.

References QLayout::addChildWidget(), QLayoutItem::alignment(), QLayoutPrivate::createWidgetItem(), d, invalidate(), it, stretch(), and QLayoutItem::widget().

Referenced by addWidget(), QWizardPrivate::recreateLayout(), and QInputDialogPrivate::setInputWidget().

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◆ invalidate()

void QBoxLayout::invalidate ( )

overridevirtual

Resets cached information.

Reimplemented from QLayoutItem.

Definition at line 670 of file qboxlayout.cpp.

References d, and QLayout::invalidate().

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

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◆ itemAt()

QLayoutItem * QBoxLayout::itemAt ( int index ) const

overridevirtual

\reimp

Implements QLayout.

Definition at line 689 of file qboxlayout.cpp.

References d.

Referenced by QGraphicsLayoutPrivate::activateRecursive(), changeSpacerSize(), hideOrShowWidgetsInLayout(), QDialogButtonBoxPrivate::layoutButtons(), paintLayout(), QWizardPrivate::updateLayout(), and QComboBoxPrivateContainer::updateTopBottomMargin().

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◆ maximumSize()

QSize QBoxLayout::maximumSize ( ) const

overridevirtual

\reimp

Implements QLayoutItem.

Definition at line 610 of file qboxlayout.cpp.

References Qt::AlignHorizontal_Mask, QLayoutItem::alignment(), Qt::AlignVertical_Mask, d, and QLAYOUTSIZE_MAX.

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◆ minimumHeightForWidth()

int QBoxLayout::minimumHeightForWidth ( int w ) const

overridevirtual

\reimp

Reimplemented from QLayoutItem.

Definition at line 658 of file qboxlayout.cpp.

References d, heightForWidth(), and void.

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◆ minimumSize()

QSize QBoxLayout::minimumSize ( ) const

overridevirtual

\reimp

Implements QLayoutItem.

Definition at line 599 of file qboxlayout.cpp.

References d.

◆ setDirection()

void QBoxLayout::setDirection ( Direction direction )

Sets the direction of this layout to direction.

Definition at line 1127 of file qboxlayout.cpp.

References d, direction(), QSizePolicy::Expanding, QSizePolicy::Fixed, horz(), i, invalidate(), QSizePolicy::Minimum, and sp.

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◆ setGeometry()

void QBoxLayout::setGeometry ( const QRect & r )

overridevirtual

\reimp

Reimplemented from QLayout.

Definition at line 733 of file qboxlayout.cpp.

References QLayoutItem::alignment(), QLayout::alignmentRect(), QRect::bottom(), BottomToTop, d, QLayout::geometry(), QRect::height(), horz(), i, j, LeftToRight, QObject::parent(), QLayout::parentWidget(), pos, qBound(), qGeomCalc(), QRect::right(), RightToLeft, QLayout::setGeometry(), TopToBottom, QRect::width(), QRect::x(), and QRect::y().

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◆ setSpacing()

void QBoxLayout::setSpacing ( int spacing )

overridevirtual

Reimplements QLayout::setSpacing().

Sets the spacing property to spacing.

See also: QLayout::setSpacing(), spacing()

Reimplemented from QLayout.

Definition at line 578 of file qboxlayout.cpp.

References d, invalidate(), and spacing().

Referenced by QCalendarWidgetPrivate::createNavigationBar(), QWizardPrivate::init(), QWizardPrivate::recreateLayout(), QStatusBar::reformat(), and QCalendarPopup::setCalendarWidget().

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◆ setStretch()

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

Sets the stretch factor at position index.

to stretch.

Since: 4.5

Definition at line 1098 of file qboxlayout.cpp.

References d, invalidate(), list, QList< T >::size(), and stretch().

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◆ setStretchFactor() [1/2]

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

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

Definition at line 1076 of file qboxlayout.cpp.

References d, i, invalidate(), QLayout::layout(), and stretch().

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◆ setStretchFactor() [2/2]

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 1053 of file qboxlayout.cpp.

References d, i, invalidate(), stretch(), and QLayoutItem::widget().

Referenced by QQuickLayoutAttached::setHorizontalStretchFactor(), and QQuickLayoutAttached::setVerticalStretchFactor().

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◆ sizeHint()

QSize QBoxLayout::sizeHint ( ) const

overridevirtual

\reimp

Implements QLayoutItem.

Definition at line 588 of file qboxlayout.cpp.

References d.

Referenced by QQuickLayoutAttached::sizeHint().

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◆ spacing()

int QBoxLayout::spacing ( ) const

overridevirtual

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()

Reimplemented from QLayout.

Definition at line 560 of file qboxlayout.cpp.

References d, LeftToRight, QStyle::PM_LayoutHorizontalSpacing, QStyle::PM_LayoutVerticalSpacing, qSmartSpacing(), and RightToLeft.

Referenced by QColorDialogPrivate::initWidgets(), and setSpacing().

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◆ stretch()

int QBoxLayout::stretch ( int index ) const

Returns the stretch factor at position index.

Since: 4.5

Definition at line 1116 of file qboxlayout.cpp.

References d, list, and QList< T >::size().

Referenced by addLayout(), addStretch(), addWidget(), insertLayout(), insertStretch(), insertWidget(), setStretch(), setStretchFactor(), and setStretchFactor().

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◆ takeAt()

QLayoutItem * QBoxLayout::takeAt ( int index )

overridevirtual

\reimp

Implements QLayout.

Definition at line 698 of file qboxlayout.cpp.

References d, invalidate(), and item.

Referenced by clearAndDestroyQLayoutItem(), QDialogButtonBoxPrivate::layoutButtons(), and QWizardPrivate::setButtonLayout().

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

qtbase/src/widgets/kernel/qboxlayout.h
qtbase/src/widgets/kernel/qboxlayout.cpp

Public Types

Public Member Functions

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ Direction

Constructor & Destructor Documentation

◆ QBoxLayout()

◆ ~QBoxLayout()

Member Function Documentation

◆ addItem()

◆ addLayout()

◆ addSpacerItem()

◆ addSpacing()

◆ addStretch()

◆ addStrut()

◆ addWidget()

◆ count()

◆ direction()

◆ expandingDirections()

◆ hasHeightForWidth()

◆ heightForWidth()

◆ insertItem()

◆ insertLayout()

◆ insertSpacerItem()

◆ insertSpacing()

◆ insertStretch()

◆ insertWidget()

◆ invalidate()

◆ itemAt()

◆ maximumSize()

◆ minimumHeightForWidth()

◆ minimumSize()

◆ setDirection()

◆ setGeometry()

◆ setSpacing()

◆ setStretch()

◆ setStretchFactor() [1/2]

◆ setStretchFactor() [2/2]

◆ sizeHint()

◆ spacing()

◆ stretch()

◆ takeAt()