QLayout Class Reference

The QLayout class is the base class of geometry managers. More...

#include <qlayout.h>

Inheritance diagram for QLayout:

Collaboration diagram for QLayout:

Public Types
enum	SizeConstraint {   SetDefaultConstraint , SetNoConstraint , SetMinimumSize , SetFixedSize ,   SetMaximumSize , SetMinAndMaxSize }

Public Member Functions
	QLayout (QWidget *parent=nullptr)
	~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)
bool	setAlignment (QLayout *l, Qt::Alignment alignment)
void	setSizeConstraint (SizeConstraint)
SizeConstraint	sizeConstraint () const
void	setMenuBar (QWidget *w)
QWidget *	menuBar () const
QWidget *	parentWidget () const
void	invalidate () override
QRect	geometry () const override
bool	activate ()
void	update ()
void	addWidget (QWidget *w)
virtual void	addItem (QLayoutItem *)=0
void	removeWidget (QWidget *w)
void	removeItem (QLayoutItem *)
Qt::Orientations	expandingDirections () const override
QSize	minimumSize () const override
QSize	maximumSize () const override
virtual void	setGeometry (const QRect &) override
virtual QLayoutItem *	itemAt (int index) const =0
virtual QLayoutItem *	takeAt (int index)=0
virtual int	indexOf (const QWidget *) const
virtual int	indexOf (const QLayoutItem *) const
virtual int	count () const =0
bool	isEmpty () const override
QSizePolicy::ControlTypes	controlTypes () const override
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
void	setEnabled (bool)
bool	isEnabled () const
void	setAlignment (Qt::Alignment a)
Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)
virtual	~QObject ()
virtual bool	event (QEvent *event)
virtual bool	eventFilter (QObject *watched, QEvent *event)
QString	objectName () const
void	setObjectName (const QString &name)
QBindable< QString >	bindableObjectName ()
bool	isWidgetType () const
bool	isWindowType () const
bool	signalsBlocked () const noexcept
bool	blockSignals (bool b) noexcept
QThread *	thread () const
void	moveToThread (QThread *thread)
int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
void	killTimer (int id)
template<typename T >
T	findChild (const QString &aName=QString(), Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
template<typename T >
QList< T >	findChildren (const QString &aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
template<typename T >
QList< T >	findChildren (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
const QObjectList &	children () const
void	setParent (QObject *parent)
void	installEventFilter (QObject *filterObj)
void	removeEventFilter (QObject *obj)
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
void	dumpObjectInfo () const
bool	setProperty (const char *name, const QVariant &value)
QVariant	property (const char *name) const
QList< QByteArray >	dynamicPropertyNames () const
QBindingStorage *	bindingStorage ()
const QBindingStorage *	bindingStorage () const
QObject *	parent () const
bool	inherits (const char *classname) const
Public Member Functions inherited from QLayoutItem
	QLayoutItem (Qt::Alignment alignment=Qt::Alignment())
virtual	~QLayoutItem ()
virtual QSize	sizeHint () const =0
virtual bool	hasHeightForWidth () const
virtual int	heightForWidth (int) const
virtual int	minimumHeightForWidth (int) const
virtual QWidget *	widget () const
virtual QSpacerItem *	spacerItem ()
Qt::Alignment	alignment () const
void	setAlignment (Qt::Alignment a)

Static Public Member Functions
static QSize	closestAcceptableSize (const QWidget *w, const QSize &s)
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)
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::FunctionPointer< Func2 >::Object *receiver, Func2 slot, Qt::ConnectionType type=Qt::AutoConnection)
static QMetaObject::Connection ::type	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 slot)
static QMetaObject::Connection ::type	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, const QObject *context, Func2 slot, Qt::ConnectionType type=Qt::AutoConnection)
template<typename Func1 , typename Func2 >
static std::enable_if< QtPrivate::FunctionPointer< Func2 >::ArgumentCount==-1 &&!std::is_convertible_v< Func2, const char * >, QMetaObject::Connection >::type	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 slot)
template<typename Func1 , typename Func2 >
static std::enable_if< QtPrivate::FunctionPointer< Func2 >::ArgumentCount==-1 &&!std::is_convertible_v< Func2, const char * >, QMetaObject::Connection >::type	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, const QObject *context, Func2 slot, Qt::ConnectionType type=Qt::AutoConnection)
static bool	disconnect (const QObject *sender, const char *signal, const QObject *receiver, const char *member)
static bool	disconnect (const QObject *sender, const QMetaMethod &signal, const QObject *receiver, const QMetaMethod &member)
static bool	disconnect (const QMetaObject::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
void	widgetEvent (QEvent *)
void	childEvent (QChildEvent *e) override
void	addChildLayout (QLayout *l)
void	addChildWidget (QWidget *w)
bool	adoptLayout (QLayout *layout)
QRect	alignmentRect (const QRect &) const
	QLayout (QLayoutPrivate &d, QLayout *, QWidget *)
Protected Member Functions inherited from QObject
QObject *	sender () const
int	senderSignalIndex () const
int	receivers (const char *signal) const
bool	isSignalConnected (const QMetaMethod &signal) const
virtual void	timerEvent (QTimerEvent *event)
virtual void	customEvent (QEvent *event)
virtual void	connectNotify (const QMetaMethod &signal)
virtual void	disconnectNotify (const QMetaMethod &signal)
	QObject (QObjectPrivate &dd, QObject *parent=nullptr)

Properties
int	spacing
	the spacing between widgets inside the layout More...
QMargins	contentsMargins
SizeConstraint	sizeConstraint
	the resize mode of the layout More...
Properties inherited from QObject
QString	objectName
	the name of this object More...

Friends
class	QApplicationPrivate
class	QWidget

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
Signals inherited from QObject
void	destroyed (QObject *=nullptr)
void	objectNameChanged (const QString &objectName, QPrivateSignal)
Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr
Protected Attributes inherited from QLayoutItem
Qt::Alignment	align
Related Functions inherited from QObject
template< class T > T	qobject_cast (const QObject *object)
template< typename T > T	qFindChildqFindChildren (const QObject *obj, const QString &name)()
template< typename T > QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()
	QObjectList

Detailed Description

The QLayout class is the base class of geometry managers.

\inmodule QtWidgets

This is an abstract base class inherited by the concrete classes QBoxLayout, QGridLayout, QFormLayout, and QStackedLayout.

For users of QLayout subclasses or of QMainWindow there is seldom any need to use the basic functions provided by QLayout, such as setSizeConstraint() or setMenuBar(). See \l{Layout Management} for more information.

To make your own layout manager, implement the functions addItem(), sizeHint(), setGeometry(), itemAt() and takeAt(). You should also implement minimumSize() to ensure your layout isn't resized to zero size if there is too little space. To support children whose heights depend on their widths, implement hasHeightForWidth() and heightForWidth(). See the \l{layouts/borderlayout}{Border Layout} and \l{layouts/flowlayout}{Flow Layout} examples for more information about implementing custom layout managers.

Geometry management stops when the layout manager is deleted.

See also

QLayoutItem, {Layout Management}, {Basic Layouts Example}, {Border Layout Example}, {Flow Layout Example}

Definition at line 61 of file qlayout.h.

Member Enumeration Documentation

SizeConstraint

enum QLayout::SizeConstraint

The possible values are:

\value SetDefaultConstraint The main widget's minimum size is set to minimumSize(), unless the widget already has a minimum size.

\value SetFixedSize The main widget's size is set to sizeHint(); it cannot be resized at all. \value SetMinimumSize The main widget's minimum size is set to minimumSize(); it cannot be smaller.

\value SetMaximumSize The main widget's maximum size is set to maximumSize(); it cannot be larger.

\value SetMinAndMaxSize The main widget's minimum size is set to minimumSize() and its maximum size is set to maximumSize().

\value SetNoConstraint The widget is not constrained.

See also

setSizeConstraint()

Enumerator
SetDefaultConstraint
SetNoConstraint
SetMinimumSize
SetFixedSize
SetMaximumSize
SetMinAndMaxSize

Definition at line 71 of file qlayout.h.

Constructor & Destructor Documentation

QLayout() [1/2]

QLayout::QLayout ( QWidget *  parent = nullptr )

explicit

Constructs a new top-level QLayout, with parent 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().

If parent is \nullptr, then you must insert this layout into another layout, or set it as a widget's layout using QWidget::setLayout().

See also

QWidget::setLayout()

Definition at line 120 of file qlayout.cpp.

~QLayout()

QLayout::~QLayout

(

)

Definition at line 734 of file qlayout.cpp.

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QLayout() [2/2]

QLayout::QLayout ( QLayoutPrivate &  d, QLayout *  lay, QWidget *  w  )

protected

Definition at line 130 of file qlayout.cpp.

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Member Function Documentation

activate()

bool QLayout::activate

(

)

Redoes the layout for parentWidget() if necessary.

You should generally not need to call this because it is automatically called at the most appropriate times. It returns true if the layout was redone.

See also

update(), QWidget::updateGeometry()

Definition at line 1028 of file qlayout.cpp.

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addChildLayout()

void QLayout::addChildLayout ( QLayout *  l )

protected

This function is called from addLayout() or insertLayout() functions in subclasses to add layout l as a sub-layout.

The only scenario in which you need to call it directly is if you implement a custom layout that supports nested layouts.

See also

QBoxLayout::addLayout(), QBoxLayout::insertLayout(), QGridLayout::addLayout()

Definition at line 753 of file qlayout.cpp.

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addChildWidget()

void QLayout::addChildWidget ( QWidget *  w )

protected

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

If w is already managed by a layout, this function will give a warning and remove w from that layout. This function must therefore be called before adding w to the layout's data structure.

Definition at line 870 of file qlayout.cpp.

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addItem()

void QLayout::addItem ( QLayoutItem *  item )

pure virtual

Implemented in subclasses to add an item. How it is added is specific to each subclass.

This function is not usually called in application code. To add a widget to a layout, use the addWidget() function; to add a child layout, use the addLayout() function provided by the relevant QLayout subclass.

{Note:} The ownership of item is transferred to the layout, and it's the layout's responsibility to delete it.

See also

addWidget(), QBoxLayout::addLayout(), QGridLayout::addLayout()

Implemented in QToolBarLayout, QMainWindowLayout, QDockWidgetLayout, QStackedLayout, QFormLayout, CardLayout, FlowLayout, BorderLayout, MyLayout, QGridLayout, and QBoxLayout.

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addWidget()

void QLayout::addWidget

(

QWidget *

w

)

Adds widget w to this layout in a manner specific to the layout. This function uses addItem().

Definition at line 223 of file qlayout.cpp.

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adoptLayout()

bool QLayout::adoptLayout ( QLayout *  layout )

protected

Definition at line 771 of file qlayout.cpp.

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alignmentRect()

QRect QLayout::alignmentRect ( const QRect &  r ) const

protected

Returns the rectangle that should be covered when the geometry of this layout is set to r, provided that this layout supports setAlignment().

The result is derived from sizeHint() and expanding(). It is never larger than r.

Definition at line 1298 of file qlayout.cpp.

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childEvent()

void QLayout::childEvent ( QChildEvent *  e )

overrideprotectedvirtual

\reimp

Reimplemented from QObject.

Definition at line 594 of file qlayout.cpp.

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closestAcceptableSize()

QSize QLayout::closestAcceptableSize ( const QWidget *  widget, const QSize &  size  )

static

Returns a size that satisfies all size constraints on widget, including heightForWidth() and that is as close as possible to size.

Definition at line 1431 of file qlayout.cpp.

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contentsMargins()

QMargins QLayout::contentsMargins

(

)

const

Since

4.6

Returns the margins used around the layout.

By default, QLayout uses the values provided by the style. On most platforms, the margin is 11 pixels in all directions.

See also

setContentsMargins()

Definition at line 403 of file qlayout.cpp.

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contentsRect()

QRect QLayout::contentsRect

(

)

const

Since

4.3

Returns the layout's geometry() rectangle, but taking into account the contents margins.

See also

setContentsMargins(), getContentsMargins()

Definition at line 418 of file qlayout.cpp.

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controlTypes()

QSizePolicy::ControlTypes QLayout::controlTypes ( ) const

overridevirtual

\reimp

Reimplemented from QLayoutItem.

Definition at line 475 of file qlayout.cpp.

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count()

int * QLayout::count ( ) const

pure virtual

Must be implemented in subclasses to return the number of items in the layout.

See also

itemAt()

Implemented in MyLayout, QToolBarLayout, QMainWindowLayout, QDockWidgetLayout, QStackedLayout, QGridLayout, QFormLayout, QBoxLayout, CardLayout, FlowLayout, BorderLayout, and FlowLayout.

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expandingDirections()

Qt::Orientations QLayout::expandingDirections ( ) const

overridevirtual

Returns whether this layout can make use of more space than sizeHint(). A value of Qt::Vertical or Qt::Horizontal means that it wants to grow in only one dimension, whereas Qt::Vertical | Qt::Horizontal means that it wants to grow in both dimensions.

The default implementation returns Qt::Horizontal | Qt::Vertical. Subclasses reimplement it to return a meaningful value based on their child widgets's \l{QSizePolicy}{size policies}.

See also

sizeHint()

Implements QLayoutItem.

Reimplemented in QToolBarLayout.

Definition at line 977 of file qlayout.cpp.

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geometry()

QRect QLayout::geometry ( ) const

overridevirtual

\reimp

Implements QLayoutItem.

Definition at line 497 of file qlayout.cpp.

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getContentsMargins()

void QLayout::getContentsMargins	(	int *	left,
		int *	top,
		int *	right,
		int *	bottom
	)		const

Since

4.3

For each of left, top, right and bottom that is not \nullptr, stores the size of the margin named in the location the pointer refers to.

By default, QLayout uses the values provided by the style. On most platforms, the margin is 11 pixels in all directions.

See also

setContentsMargins(), QStyle::pixelMetric(), {QStyle::}{PM_LayoutLeftMargin}, {QStyle::}{PM_LayoutTopMargin}, {QStyle::}{PM_LayoutRightMargin}, {QStyle::}{PM_LayoutBottomMargin}

Definition at line 384 of file qlayout.cpp.

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indexOf() [1/2]

int QLayout::indexOf ( const QLayoutItem *  layoutItem ) const

virtual

Since

5.12 Searches for layout item layoutItem in this layout (not including child layouts).

Returns the index of layoutItem, or -1 if layoutItem is not found.

Definition at line 1229 of file qlayout.cpp.

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indexOf() [2/2]

int QLayout::indexOf ( const QWidget *  widget ) const

virtual

Searches for widget widget in this layout (not including child layouts).

Returns the index of widget, or -1 if widget is not found.

The default implementation iterates over all items using itemAt().

Definition at line 1210 of file qlayout.cpp.

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invalidate()

void QLayout::invalidate ( )

overridevirtual

\reimp

Reimplemented from QLayoutItem.

Reimplemented in MyLayout, QToolBarLayout, and QMainWindowLayout.

Definition at line 506 of file qlayout.cpp.

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isEmpty()

bool QLayout::isEmpty ( ) const

overridevirtual

\reimp

Implements QLayoutItem.

Reimplemented in QToolBarLayout.

Definition at line 459 of file qlayout.cpp.

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isEnabled()

bool QLayout::isEnabled

(

)

const

Returns true if the layout is enabled; otherwise returns false.

See also

setEnabled()

Definition at line 1419 of file qlayout.cpp.

itemAt()

QLayoutItem * QLayout::itemAt ( int  index ) const

pure virtual

Must be implemented in subclasses to return the layout item at index. If there is no such item, the function must return \nullptr. Items are numbered consecutively from 0. If an item is deleted, other items will be renumbered.

This function can be used to iterate over a layout. The following code will draw a rectangle for each layout item in the layout structure of the widget.

See also

count(), takeAt()

Implemented in MyLayout, QStackedLayout, QBoxLayout, CardLayout, QToolBarLayout, QMainWindowLayout, QDockWidgetLayout, QGridLayout, QFormLayout, FlowLayout, BorderLayout, and FlowLayout.

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layout()

QLayout * QLayout::layout ( )

overridevirtual

\reimp

Reimplemented from QLayoutItem.

Definition at line 333 of file qlayoutitem.cpp.

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maximumSize()

QSize QLayout::maximumSize ( ) const

overridevirtual

Returns the maximum size of this layout. This is the largest size that the layout can have while still respecting the specifications.

The returned value doesn't include the space required by QWidget::setContentsMargins() or menuBar().

The default implementation allows unlimited resizing.

Implements QLayoutItem.

Reimplemented in QDockWidgetLayout.

Definition at line 960 of file qlayout.cpp.

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menuBar()

QWidget * QLayout::menuBar

(

)

const

Returns the menu bar set for this layout, or \nullptr if no menu bar is set.

Definition at line 928 of file qlayout.cpp.

minimumSize()

QSize QLayout::minimumSize ( ) const

overridevirtual

Returns the minimum size of this layout. This is the smallest size that the layout can have while still respecting the specifications.

The returned value doesn't include the space required by QWidget::setContentsMargins() or menuBar().

The default implementation allows unlimited resizing.

Implements QLayoutItem.

Reimplemented in QToolBarLayout, QMainWindowLayout, QDockWidgetLayout, and QStackedLayout.

Definition at line 945 of file qlayout.cpp.

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parentWidget()

QWidget * QLayout::parentWidget

(

)

const

Returns the parent widget of this layout, or \nullptr if this layout is not installed on any widget.

If the layout is a sub-layout, this function returns the parent widget of the parent layout.

See also

parent()

Definition at line 436 of file qlayout.cpp.

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removeItem()

void QLayout::removeItem

(

QLayoutItem *

item

)

Removes the layout item item from the layout. It is the caller's responsibility to delete the item.

Notice that item can be a layout (since QLayout inherits QLayoutItem).

See also

removeWidget(), addItem()

Definition at line 1384 of file qlayout.cpp.

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removeWidget()

void QLayout::removeWidget

(

QWidget *

widget

)

Removes the widget widget from the layout. After this call, it is the caller's responsibility to give the widget a reasonable geometry or to put the widget back into a layout or to explicitly hide it if necessary.

{Note:} The ownership of widget remains the same as when it was added.

See also

removeItem(), QWidget::setGeometry(), addWidget()

Definition at line 1356 of file qlayout.cpp.

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replaceWidget()

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

virtual

Since

5.2

Searches for widget from and replaces it with widget to if found. Returns the layout item that contains the widget from on success. Otherwise \nullptr is returned. If options contains Qt::FindChildrenRecursively (the default), sub-layouts are searched for doing the replacement. Any other flag in options is ignored.

Notice that the returned item therefore might not belong to this layout, but to a sub-layout.

The returned layout item is no longer owned by the layout and should be either deleted or inserted to another layout. The widget from is no longer managed by the layout and may need to be deleted or hidden. The parent of widget from is left unchanged.

This function works for the built-in Qt layouts, but might not work for custom layouts.

See also

indexOf()

Definition at line 1123 of file qlayout.cpp.

setAlignment() [1/3]

bool QLayout::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.

Definition at line 259 of file qlayout.cpp.

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setAlignment() [2/3]

void QLayoutItem::setAlignment

Sets the alignment of this item to alignment.

{Note:} Item alignment is only supported by QLayoutItem subclasses where it would have a visual effect. Except for QSpacerItem, which provides blank space for layouts, all public Qt classes that inherit QLayoutItem support item alignment.

Definition at line 82 of file qlayoutitem.cpp.

setAlignment() [3/3]

bool QLayout::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.

Definition at line 236 of file qlayout.cpp.

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setContentsMargins() [1/2]

void QLayout::setContentsMargins

(

const QMargins &

margins

)

Since

4.6

Sets the margins to use around the layout.

By default, QLayout uses the values provided by the style. On most platforms, the margin is 11 pixels in all directions.

See also

contentsMargins()

Definition at line 350 of file qlayout.cpp.

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setContentsMargins() [2/2]

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

Since

4.3

Sets the left, top, right, and bottom margins to use around the layout.

By default, QLayout uses the values provided by the style. On most platforms, the margin is 11 pixels in all directions.

See also

getContentsMargins(), QStyle::pixelMetric(), {QStyle::}{PM_LayoutLeftMargin}, {QStyle::}{PM_LayoutTopMargin}, {QStyle::}{PM_LayoutRightMargin}, {QStyle::}{PM_LayoutBottomMargin}

Definition at line 325 of file qlayout.cpp.

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setEnabled()

void QLayout::setEnabled

(

bool

enable

)

Enables this layout if enable is true, otherwise disables it.

An enabled layout adjusts dynamically to changes; a disabled layout acts as if it did not exist.

By default all layouts are enabled.

See also

isEnabled()

Definition at line 1408 of file qlayout.cpp.

setGeometry()

void QLayout::setGeometry ( const QRect &  r )

overridevirtual

\reimp

Implements QLayoutItem.

Reimplemented in QStackedLayout, QFormLayout, CardLayout, FlowLayout, BorderLayout, QToolBarLayout, QMainWindowLayout, QDockWidgetLayout, QGridLayout, and QBoxLayout.

Definition at line 488 of file qlayout.cpp.

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setMenuBar()

void QLayout::setMenuBar

(

QWidget *

widget

)

Tells the geometry manager to place the menu bar widget at the top of parentWidget(), outside QWidget::contentsMargins(). All child widgets are placed below the bottom edge of the menu bar.

Definition at line 915 of file qlayout.cpp.

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setSizeConstraint()

void QLayout::setSizeConstraint

(

SizeConstraint

constraint

)

Definition at line 1274 of file qlayout.cpp.

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setSpacing()

void QLayout::setSpacing ( int  spacing )

virtual

Reimplemented in QFormLayout, QGridLayout, and QBoxLayout.

Definition at line 303 of file qlayout.cpp.

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sizeConstraint()

QLayout::SizeConstraint QLayout::sizeConstraint

(

)

const

Definition at line 1284 of file qlayout.cpp.

spacing()

int QLayout::spacing ( ) const

virtual

Reimplemented in QGridLayout, QFormLayout, and QBoxLayout.

Definition at line 292 of file qlayout.cpp.

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takeAt()

QLayoutItem * QLayout::takeAt ( int  index )

pure virtual

Must be implemented in subclasses to remove the layout item at index from the layout, and return the item. If there is no such item, the function must do nothing and return 0. Items are numbered consecutively from 0. If an item is removed, other items will be renumbered.

The following code fragment shows a safe way to remove all items from a layout:

See also

itemAt(), count()

Implemented in MyLayout, QStackedLayout, QBoxLayout, CardLayout, QToolBarLayout, QMainWindowLayout, QDockWidgetLayout, QGridLayout, QFormLayout, FlowLayout, and BorderLayout.

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totalHeightForWidth()

int QLayout::totalHeightForWidth

(

int

w

)

const

Definition at line 633 of file qlayout.cpp.

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totalMaximumSize()

QSize QLayout::totalMaximumSize

(

)

const

Definition at line 703 of file qlayout.cpp.

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totalMinimumHeightForWidth()

int QLayout::totalMinimumHeightForWidth

(

int

w

)

const

Definition at line 611 of file qlayout.cpp.

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totalMinimumSize()

QSize QLayout::totalMinimumSize

(

)

const

Definition at line 655 of file qlayout.cpp.

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totalSizeHint()

QSize QLayout::totalSizeHint

(

)

const

Definition at line 678 of file qlayout.cpp.

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unsetContentsMargins()

void QLayout::unsetContentsMargins

(

)

Since

6.1

Unsets any user-defined margins around the layout. The layout will use the default values provided by the style.

See also

setContentsMargins()

Definition at line 363 of file qlayout.cpp.

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update()

void QLayout::update

(

)

Updates the layout for parentWidget().

You should generally not need to call this because it is automatically called at the most appropriate times.

See also

activate(), invalidate()

Definition at line 1004 of file qlayout.cpp.

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widgetEvent()

void QLayout::widgetEvent ( QEvent *  e )

protected

Definition at line 557 of file qlayout.cpp.

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Friends And Related Function Documentation

QApplicationPrivate

friend class QApplicationPrivate

friend

Definition at line 160 of file qlayout.h.

QWidget

friend class QWidget

friend

Definition at line 161 of file qlayout.h.

Property Documentation

contentsMargins

QMargins QLayout::contentsMargins

readwrite

Definition at line 165 of file qlayout.h.

sizeConstraint

QLayout::sizeConstraint

readwrite

the resize mode of the layout

The default mode is \l {QLayout::SetDefaultConstraint} {SetDefaultConstraint}.

Definition at line 165 of file qlayout.h.

spacing

QLayout::spacing

readwrite

the spacing between widgets inside the layout

If no value is explicitly set, the layout's spacing is inherited from the parent layout, or from the style settings for the parent widget.

For QGridLayout and QFormLayout, it is possible to set different horizontal and vertical spacings using \l{QGridLayout::}{setHorizontalSpacing()} and \l{QGridLayout::}{setVerticalSpacing()}. In that case, spacing() returns -1.

See also

contentsRect(), getContentsMargins(), QStyle::layoutSpacing(), QStyle::pixelMetric()

Definition at line 165 of file qlayout.h.

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

• src/widgets/kernel/qlayout.h
• src/widgets/kernel/qlayout.cpp
• src/widgets/kernel/qlayoutitem.cpp