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QSpacerItem Class

The QSpacerItem class provides blank space in a layout. More...

Header:	#include <QSpacerItem>
CMake:	find_package(Qt6 COMPONENTS Widgets REQUIRED) target_link_libraries(mytarget PRIVATE Qt6::Widgets)
qmake:	QT += widgets
Inherits:	QLayoutItem

List of all members, including inherited members

Public Functions

	QSpacerItem(int w, int h, QSizePolicy::Policy hPolicy = QSizePolicy::Minimum, QSizePolicy::Policy vPolicy = QSizePolicy::Minimum)
virtual	~QSpacerItem()
void	changeSize(int w, int h, QSizePolicy::Policy hPolicy = QSizePolicy::Minimum, QSizePolicy::Policy vPolicy = QSizePolicy::Minimum)
QSizePolicy	sizePolicy() const

Reimplemented Public Functions

virtual Qt::Orientations	expandingDirections() const override
virtual QRect	geometry() const override
virtual bool	isEmpty() const override
virtual QSize	maximumSize() const override
virtual QSize	minimumSize() const override
virtual void	setGeometry(const QRect &r) override
virtual QSize	sizeHint() const override
virtual QSpacerItem *	spacerItem() override

Detailed Description

Normally, you don't need to use this class directly. Qt's built-in layout managers provide the following functions for manipulating empty space in layouts:

Class	Functions
QHBoxLayout	addSpacing(), addStretch(), insertSpacing(), insertStretch()
QGridLayout	setRowMinimumHeight(), setRowStretch(), setColumnMinimumWidth(), setColumnStretch()

See also QLayout, QWidgetItem, and QLayoutItem::spacerItem().

Member Function Documentation

QSpacerItem::QSpacerItem(int w, int h, QSizePolicy::Policy hPolicy = QSizePolicy::Minimum, QSizePolicy::Policy vPolicy = QSizePolicy::Minimum)

Constructs a spacer item with preferred width w, preferred height h, horizontal size policy hPolicy and vertical size policy vPolicy.

The default values provide a gap that is able to stretch if nothing else wants the space.

`[virtual]` QSpacerItem::~QSpacerItem()

Destructor.

void QSpacerItem::changeSize(int w, int h, QSizePolicy::Policy hPolicy = QSizePolicy::Minimum, QSizePolicy::Policy vPolicy = QSizePolicy::Minimum)

Changes this spacer item to have preferred width w, preferred height h, horizontal size policy hPolicy and vertical size policy vPolicy.

The default values provide a gap that is able to stretch if nothing else wants the space.

Note that if changeSize() is called after the spacer item has been added to a layout, it is necessary to invalidate the layout in order for the spacer item's new size to take effect.

See also QSpacerItem::invalidate().