The QLabel widget provides a text or image display. More...

#include <qlabel.h>

Inheritance diagram for QLabel:

Collaboration diagram for QLabel:

Public Slots
void	setText (const QString &)

void	setPixmap (const QPixmap &)

void	setPicture (const QPicture &)

void	setNum (int)

void	setNum (double)

void	clear ()

Public Slots inherited from QWidget
void	setEnabled (bool)

void	setDisabled (bool)

void	setWindowModified (bool)

void	setWindowTitle (const QString &)

void	setStyleSheet (const QString &styleSheet)

void	setFocus ()

void	update ()

void	repaint ()

virtual void	setVisible (bool visible)

void	setHidden (bool hidden)

void	show ()

void	hide ()

void	showMinimized ()

void	showMaximized ()

void	showFullScreen ()

void	showNormal ()

bool	close ()

void	raise ()

void	lower ()

Public Slots inherited from QObject
void	deleteLater ()

Signals
void	linkActivated (const QString &link)

void	linkHovered (const QString &link)

Signals inherited from QWidget
void	windowTitleChanged (const QString &title)

void	windowIconChanged (const QIcon &icon)

void	windowIconTextChanged (const QString &iconText)

void	customContextMenuRequested (const QPoint &pos)

Signals inherited from QObject
void	destroyed (QObject *=nullptr)

void	objectNameChanged (const QString &objectName, QPrivateSignal)

Public Member Functions
	QLabel (QWidget *parent=nullptr, Qt::WindowFlags f=Qt::WindowFlags())

	QLabel (const QString &text, QWidget *parent=nullptr, Qt::WindowFlags f=Qt::WindowFlags())

	~QLabel ()

QString	text () const

QPixmap	pixmap () const

QPicture	picture () const

Qt::TextFormat	textFormat () const

void	setTextFormat (Qt::TextFormat)

QTextDocument::ResourceProvider	resourceProvider () const

void	setResourceProvider (const QTextDocument::ResourceProvider &provider)

Qt::Alignment	alignment () const

void	setAlignment (Qt::Alignment)

void	setWordWrap (bool on)

bool	wordWrap () const

int	indent () const

void	setIndent (int)

int	margin () const

void	setMargin (int)

bool	hasScaledContents () const

void	setScaledContents (bool)

QSize	sizeHint () const override

QSize	minimumSizeHint () const override

void	setBuddy (QWidget *)

QWidget *	buddy () const

int	heightForWidth (int) const override

bool	openExternalLinks () const

void	setOpenExternalLinks (bool open)

void	setTextInteractionFlags (Qt::TextInteractionFlags flags)

Qt::TextInteractionFlags	textInteractionFlags () const

void	setSelection (int, int)

bool	hasSelectedText () const

QString	selectedText () const

int	selectionStart () const

Public Member Functions inherited from QFrame
	QFrame (QWidget *parent=nullptr, Qt::WindowFlags f=Qt::WindowFlags())

	~QFrame ()

int	frameStyle () const

void	setFrameStyle (int)

int	frameWidth () const

Shape	frameShape () const

void	setFrameShape (Shape)

Shadow	frameShadow () const

void	setFrameShadow (Shadow)

int	lineWidth () const

void	setLineWidth (int)

int	midLineWidth () const

void	setMidLineWidth (int)

QRect	frameRect () const

void	setFrameRect (const QRect &)

Public Member Functions inherited from QWidget
	QWidget (QWidget *parent=nullptr, Qt::WindowFlags f=Qt::WindowFlags())

	~QWidget ()

int	devType () const override

WId	winId () const

void	createWinId ()

WId	internalWinId () const

WId	effectiveWinId () const

QStyle *	style () const

void	setStyle (QStyle *)

bool	isWindow () const

bool	isModal () const

Qt::WindowModality	windowModality () const

void	setWindowModality (Qt::WindowModality windowModality)

bool	isEnabled () const

bool	isEnabledTo (const QWidget *) const

QRect	frameGeometry () const

const QRect &	geometry () const

QRect	normalGeometry () const

int	x () const

int	y () const

QPoint	pos () const

QSize	frameSize () const

QSize	size () const

int	width () const

int	height () const

QRect	rect () const

QRect	childrenRect () const

QRegion	childrenRegion () const

QSize	minimumSize () const

QSize	maximumSize () const

int	minimumWidth () const

int	minimumHeight () const

int	maximumWidth () const

int	maximumHeight () const

void	setMinimumSize (const QSize &)

void	setMinimumSize (int minw, int minh)

void	setMaximumSize (const QSize &)

void	setMaximumSize (int maxw, int maxh)

void	setMinimumWidth (int minw)

void	setMinimumHeight (int minh)

void	setMaximumWidth (int maxw)

void	setMaximumHeight (int maxh)

QSize	sizeIncrement () const

void	setSizeIncrement (const QSize &)

void	setSizeIncrement (int w, int h)

QSize	baseSize () const

void	setBaseSize (const QSize &)

void	setBaseSize (int basew, int baseh)

void	setFixedSize (const QSize &)

void	setFixedSize (int w, int h)

void	setFixedWidth (int w)

void	setFixedHeight (int h)

QPointF	mapToGlobal (const QPointF &) const

QPoint	mapToGlobal (const QPoint &) const

QPointF	mapFromGlobal (const QPointF &) const

QPoint	mapFromGlobal (const QPoint &) const

QPointF	mapToParent (const QPointF &) const

QPoint	mapToParent (const QPoint &) const

QPointF	mapFromParent (const QPointF &) const

QPoint	mapFromParent (const QPoint &) const

QPointF	mapTo (const QWidget *, const QPointF &) const

QPoint	mapTo (const QWidget *, const QPoint &) const

QPointF	mapFrom (const QWidget *, const QPointF &) const

QPoint	mapFrom (const QWidget *, const QPoint &) const

QWidget *	window () const

QWidget *	nativeParentWidget () const

QWidget *	topLevelWidget () const

const QPalette &	palette () const

void	setPalette (const QPalette &)

void	setBackgroundRole (QPalette::ColorRole)

QPalette::ColorRole	backgroundRole () const

void	setForegroundRole (QPalette::ColorRole)

QPalette::ColorRole	foregroundRole () const

const QFont &	font () const

void	setFont (const QFont &)

QFontMetrics	fontMetrics () const

QFontInfo	fontInfo () const

QCursor	cursor () const

void	setCursor (const QCursor &)

void	unsetCursor ()

void	setMouseTracking (bool enable)

bool	hasMouseTracking () const

bool	underMouse () const

void	setTabletTracking (bool enable)

bool	hasTabletTracking () const

void	setMask (const QBitmap &)

void	setMask (const QRegion &)

QRegion	mask () const

void	clearMask ()

void	render (QPaintDevice *target, const QPoint &targetOffset=QPoint(), const QRegion &sourceRegion=QRegion(), RenderFlags renderFlags=RenderFlags(DrawWindowBackground\|DrawChildren))

void	render (QPainter *painter, const QPoint &targetOffset=QPoint(), const QRegion &sourceRegion=QRegion(), RenderFlags renderFlags=RenderFlags(DrawWindowBackground\|DrawChildren))

Q_INVOKABLE QPixmap	grab (const QRect &rectangle=QRect(QPoint(0, 0), QSize(-1, -1)))

void	grabGesture (Qt::GestureType type, Qt::GestureFlags flags=Qt::GestureFlags())

void	ungrabGesture (Qt::GestureType type)

QString	styleSheet () const

QString	windowTitle () const

void	setWindowIcon (const QIcon &icon)

QIcon	windowIcon () const

void	setWindowIconText (const QString &)

QString	windowIconText () const

void	setWindowRole (const QString &)

QString	windowRole () const

void	setWindowFilePath (const QString &filePath)

QString	windowFilePath () const

void	setWindowOpacity (qreal level)

qreal	windowOpacity () const

bool	isWindowModified () const

QString	accessibleName () const

void	setAccessibleName (const QString &name)

QString	accessibleDescription () const

void	setAccessibleDescription (const QString &description)

void	setLayoutDirection (Qt::LayoutDirection direction)

Qt::LayoutDirection	layoutDirection () const

void	unsetLayoutDirection ()

void	setLocale (const QLocale &locale)

QLocale	locale () const

void	unsetLocale ()

bool	isRightToLeft () const

bool	isLeftToRight () const

bool	isActiveWindow () const

void	activateWindow ()

void	clearFocus ()

void	setFocus (Qt::FocusReason reason)

Qt::FocusPolicy	focusPolicy () const

void	setFocusPolicy (Qt::FocusPolicy policy)

bool	hasFocus () const

void	setFocusProxy (QWidget *)

QWidget *	focusProxy () const

Qt::ContextMenuPolicy	contextMenuPolicy () const

void	setContextMenuPolicy (Qt::ContextMenuPolicy policy)

void	grabMouse ()

void	grabMouse (const QCursor &)

void	releaseMouse ()

void	grabKeyboard ()

void	releaseKeyboard ()

int	grabShortcut (const QKeySequence &key, Qt::ShortcutContext context=Qt::WindowShortcut)

void	releaseShortcut (int id)

void	setShortcutEnabled (int id, bool enable=true)

void	setShortcutAutoRepeat (int id, bool enable=true)

bool	updatesEnabled () const

void	setUpdatesEnabled (bool enable)

void	update (int x, int y, int w, int h)

void	update (const QRect &)

void	update (const QRegion &)

void	repaint (int x, int y, int w, int h)

void	repaint (const QRect &)

void	repaint (const QRegion &)

void	stackUnder (QWidget *)

void	move (int x, int y)

void	move (const QPoint &)

void	resize (int w, int h)

void	resize (const QSize &)

void	setGeometry (int x, int y, int w, int h)

void	setGeometry (const QRect &)

QByteArray	saveGeometry () const

bool	restoreGeometry (const QByteArray &geometry)

void	adjustSize ()

bool	isVisible () const

bool	isVisibleTo (const QWidget *) const

bool	isHidden () const

bool	isMinimized () const

bool	isMaximized () const

bool	isFullScreen () const

Qt::WindowStates	windowState () const

void	setWindowState (Qt::WindowStates state)

void	overrideWindowState (Qt::WindowStates state)

QSizePolicy	sizePolicy () const

void	setSizePolicy (QSizePolicy)

void	setSizePolicy (QSizePolicy::Policy horizontal, QSizePolicy::Policy vertical)

virtual bool	hasHeightForWidth () const

QRegion	visibleRegion () const

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

void	setContentsMargins (const QMargins &margins)
	The setContentsMargins function sets the margins around the widget's contents. More...

QMargins	contentsMargins () const
	The contentsMargins function returns the widget's contents margins. More...

QRect	contentsRect () const

QLayout *	layout () const

void	setLayout (QLayout *)

void	updateGeometry ()

void	setParent (QWidget *parent)

void	setParent (QWidget *parent, Qt::WindowFlags f)

void	scroll (int dx, int dy)

void	scroll (int dx, int dy, const QRect &)

QWidget *	focusWidget () const

QWidget *	nextInFocusChain () const

QWidget *	previousInFocusChain () const
	The previousInFocusChain function returns the previous widget in this widget's focus chain. More...

bool	acceptDrops () const

void	setAcceptDrops (bool on)

void	addAction (QAction *action)

void	addActions (const QList< QAction * > &actions)

void	insertActions (QAction before, const QList< QAction > &actions)

void	insertAction (QAction before, QAction action)

void	removeAction (QAction *action)

QList< QAction * >	actions () const

QAction *	addAction (const QString &text)

QAction *	addAction (const QIcon &icon, const QString &text)

QAction *	addAction (const QString &text, const QObject receiver, const char member, Qt::ConnectionType type=Qt::AutoConnection)

QAction *	addAction (const QIcon &icon, const QString &text, const QObject receiver, const char member, Qt::ConnectionType type=Qt::AutoConnection)

template<typename... Args, typename = compatible_action_slot_args<Args...>>
QAction *	addAction (const QString &text, Args &&...args)

template<typename... Args, typename = compatible_action_slot_args<Args...>>
QAction *	addAction (const QIcon &icon, const QString &text, Args &&...args)

QWidget *	parentWidget () const

void	setWindowFlags (Qt::WindowFlags type)

Qt::WindowFlags	windowFlags () const

void	setWindowFlag (Qt::WindowType, bool on=true)

void	overrideWindowFlags (Qt::WindowFlags type)

Qt::WindowType	windowType () const

QWidget *	childAt (int x, int y) const

QWidget *	childAt (const QPoint &p) const

void	setAttribute (Qt::WidgetAttribute, bool on=true)

bool	testAttribute (Qt::WidgetAttribute) const

QPaintEngine *	paintEngine () const override

void	ensurePolished () const

bool	isAncestorOf (const QWidget *child) const

bool	autoFillBackground () const

void	setAutoFillBackground (bool enabled)

QBackingStore *	backingStore () const

QWindow *	windowHandle () const

QScreen *	screen () const

void	setScreen (QScreen *)

virtual QVariant	inputMethodQuery (Qt::InputMethodQuery) const

Qt::InputMethodHints	inputMethodHints () const

void	setInputMethodHints (Qt::InputMethodHints hints)

Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)

virtual	~QObject ()

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 QPaintDevice
virtual	~QPaintDevice ()

bool	paintingActive () const

int	width () const

int	height () const

int	widthMM () const

int	heightMM () const

int	logicalDpiX () const

int	logicalDpiY () const

int	physicalDpiX () const

int	physicalDpiY () const

qreal	devicePixelRatio () const

qreal	devicePixelRatioF () const

int	colorCount () const

int	depth () const

Protected Member Functions
bool	event (QEvent *e) override

void	keyPressEvent (QKeyEvent *ev) override

void	paintEvent (QPaintEvent *) override

void	changeEvent (QEvent *) override

void	mousePressEvent (QMouseEvent *ev) override

void	mouseMoveEvent (QMouseEvent *ev) override

void	mouseReleaseEvent (QMouseEvent *ev) override

void	contextMenuEvent (QContextMenuEvent *ev) override

void	focusInEvent (QFocusEvent *ev) override

void	focusOutEvent (QFocusEvent *ev) override

bool	focusNextPrevChild (bool next) override

Protected Member Functions inherited from QFrame
void	drawFrame (QPainter *)

	QFrame (QFramePrivate &dd, QWidget *parent=nullptr, Qt::WindowFlags f=Qt::WindowFlags())

virtual void	initStyleOption (QStyleOptionFrame *option) const

Protected Member Functions inherited from QWidget
virtual void	mouseDoubleClickEvent (QMouseEvent *event)

virtual void	keyReleaseEvent (QKeyEvent *event)

virtual void	enterEvent (QEnterEvent *event)

virtual void	leaveEvent (QEvent *event)

virtual void	moveEvent (QMoveEvent *event)

virtual void	resizeEvent (QResizeEvent *event)

virtual void	closeEvent (QCloseEvent *event)

virtual void	actionEvent (QActionEvent *event)

virtual void	showEvent (QShowEvent *event)

virtual void	hideEvent (QHideEvent *event)

virtual bool	nativeEvent (const QByteArray &eventType, void message, qintptr result)

int	metric (PaintDeviceMetric) const override

void	initPainter (QPainter *painter) const override

QPaintDevice *	redirected (QPoint *offset) const override

QPainter *	sharedPainter () const override

virtual void	inputMethodEvent (QInputMethodEvent *)

void	create (WId=0, bool initializeWindow=true, bool destroyOldWindow=true)

void	destroy (bool destroyWindow=true, bool destroySubWindows=true)

bool	focusNextChild ()

bool	focusPreviousChild ()

	QWidget (QWidgetPrivate &d, QWidget *parent, Qt::WindowFlags f)

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	childEvent (QChildEvent *event)

virtual void	customEvent (QEvent *event)

virtual void	connectNotify (const QMetaMethod &signal)

virtual void	disconnectNotify (const QMetaMethod &signal)

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

Protected Member Functions inherited from QPaintDevice
	QPaintDevice () noexcept

Properties
QString	text
	the label's text More...

Qt::TextFormat	textFormat
	the label's text format More...

QPixmap	pixmap
	the label's pixmap. More...

bool	scaledContents
	whether the label will scale its contents to fill all available space. More...

Qt::Alignment	alignment
	the alignment of the label's contents More...

bool	wordWrap
	the label's word-wrapping policy More...

int	margin
	the width of the margin More...

int	indent
	the label's text indent in pixels More...

bool	openExternalLinks

Qt::TextInteractionFlags	textInteractionFlags

bool	hasSelectedText
	whether there is any text selected More...

QString	selectedText
	the selected text More...

Properties inherited from QFrame
Shape	frameShape
	the frame shape value from the frame style More...

Shadow	frameShadow
	the frame shadow value from the frame style More...

int	lineWidth
	the line width More...

int	midLineWidth
	the width of the mid-line More...

int	frameWidth
	the width of the frame that is drawn. More...

QRect	frameRect
	the frame's rectangle More...

Properties inherited from QWidget
bool	modal
	whether the widget is a modal widget More...

Qt::WindowModality	windowModality
	which windows are blocked by the modal widget More...

bool	enabled
	whether the widget is enabled More...

QRect	geometry
	the geometry of the widget relative to its parent and excluding the window frame More...

QRect	frameGeometry
	geometry of the widget relative to its parent including any window frame More...

QRect	normalGeometry
	the geometry of the widget as it will appear when shown as a normal (not maximized or full screen) top-level widget More...

int	x
	the x coordinate of the widget relative to its parent including any window frame More...

int	y
	the y coordinate of the widget relative to its parent and including any window frame More...

QPoint	pos
	the position of the widget within its parent widget More...

QSize	frameSize
	the size of the widget including any window frame More...

QSize	size
	the size of the widget excluding any window frame More...

int	width
	the width of the widget excluding any window frame More...

int	height
	the height of the widget excluding any window frame More...

QRect	rect
	the internal geometry of the widget excluding any window frame More...

QRect	childrenRect
	the bounding rectangle of the widget's children More...

QRegion	childrenRegion
	the combined region occupied by the widget's children More...

QSizePolicy	sizePolicy
	the default layout behavior of the widget More...

QSize	minimumSize
	the widget's minimum size More...

QSize	maximumSize
	the widget's maximum size in pixels More...

int	minimumWidth
	the widget's minimum width in pixels More...

int	minimumHeight
	the widget's minimum height in pixels More...

int	maximumWidth
	the widget's maximum width in pixels More...

int	maximumHeight
	the widget's maximum height in pixels More...

QSize	sizeIncrement
	the size increment of the widget More...

QSize	baseSize
	the base size of the widget More...

QPalette	palette
	the widget's palette More...

QFont	font
	the font currently set for the widget More...

QCursor	cursor
	the cursor shape for this widget More...

bool	mouseTracking
	whether mouse tracking is enabled for the widget More...

bool	tabletTracking
	whether tablet tracking is enabled for the widget More...

bool	isActiveWindow
	whether this widget's window is the active window More...

Qt::FocusPolicy	focusPolicy
	the way the widget accepts keyboard focus More...

bool	focus
	whether this widget (or its focus proxy) has the keyboard input focus More...

Qt::ContextMenuPolicy	contextMenuPolicy
	how the widget shows a context menu More...

bool	updatesEnabled
	whether updates are enabled More...

bool	visible
	whether the widget is visible More...

bool	minimized
	whether this widget is minimized (iconified) More...

bool	maximized
	whether this widget is maximized More...

bool	fullScreen
	whether the widget is shown in full screen mode More...

QSize	sizeHint
	the recommended size for the widget More...

QSize	minimumSizeHint
	the recommended minimum size for the widget More...

bool	acceptDrops
	whether drop events are enabled for this widget More...

QString	windowTitle
	the window title (caption) More...

QIcon	windowIcon
	the widget's icon More...

QString	windowIconText
	the text to be displayed on the icon of a minimized window More...

double	windowOpacity
	The level of opacity for the window. More...

bool	windowModified
	whether the document shown in the window has unsaved changes More...

QString	accessibleName
	the widget's name as seen by assistive technologies More...

QString	accessibleDescription
	the widget's description as seen by assistive technologies More...

Qt::LayoutDirection	layoutDirection
	the layout direction for this widget. More...

bool	autoFillBackground
	whether the widget background is filled automatically More...

QString	styleSheet
	the widget's style sheet More...

QLocale	locale
	the widget's locale More...

QString	windowFilePath
	the file path associated with a widget More...

Qt::InputMethodHints	inputMethodHints
	What input method specific hints the widget has. More...

Properties inherited from QObject
QString	objectName
	the name of this object More...

Friends
class	QMessageBoxPrivate

class	QBalloonTip

Additional Inherited Members
Public Types inherited from QFrame
enum	Shape { NoFrame = 0 , Box = 0x0001 , Panel = 0x0002 , WinPanel = 0x0003 , HLine = 0x0004 , VLine = 0x0005 , StyledPanel = 0x0006 }

enum	Shadow { Plain = 0x0010 , Raised = 0x0020 , Sunken = 0x0030 }

enum	StyleMask { Shadow_Mask = 0x00f0 , Shape_Mask = 0x000f }

Public Types inherited from QWidget
enum	RenderFlag { DrawWindowBackground = 0x1 , DrawChildren = 0x2 , IgnoreMask = 0x4 }

Public Types inherited from QPaintDevice
enum	PaintDeviceMetric { PdmWidth = 1 , PdmHeight , PdmWidthMM , PdmHeightMM , PdmNumColors , PdmDepth , PdmDpiX , PdmDpiY , PdmPhysicalDpiX , PdmPhysicalDpiY , PdmDevicePixelRatio , PdmDevicePixelRatioScaled }

Static Public Member Functions inherited from QWidget
static void	setTabOrder (QWidget , QWidget )

static QWidget *	mouseGrabber ()

static QWidget *	keyboardGrabber ()

static QWidget *	find (WId)

static QWidget *	createWindowContainer (QWindow window, QWidget parent=nullptr, Qt::WindowFlags flags=Qt::WindowFlags())

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)

Static Public Member Functions inherited from QPaintDevice
static qreal	devicePixelRatioFScale ()

Protected Slots inherited from QWidget
void	updateMicroFocus (Qt::InputMethodQuery query=Qt::ImQueryAll)

Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr

Protected Attributes inherited from QPaintDevice
ushort	painters

Related Functions inherited from QWidget
	setupUi (QWidget *widget)

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 QLabel widget provides a text or image display.

\inmodule QtWidgets

QLabel is used for displaying text or an image. No user interaction functionality is provided. The visual appearance of the label can be configured in various ways, and it can be used for specifying a focus mnemonic key for another widget.

A QLabel can contain any of the following content types:

\table \header

Content
Setting \row
Plain text
Pass a QString to setText(). \row
Rich text
Pass a QString that contains rich text to setText(). \row
A pixmap
Pass a QPixmap to setPixmap(). \row
A movie
Pass a QMovie to setMovie(). \row
A number
Pass an int or a double to setNum(), which converts the number to plain text. \row
Nothing
The same as an empty plain text. This is the default. Set by clear(). \endtable

Warning: When passing a QString to the constructor or calling setText(), make sure to sanitize your input, as QLabel tries to guess whether it displays the text as plain text or as rich text, a subset of HTML 4 markup. You may want to call setTextFormat() explicitly, e.g. in case you expect the text to be in plain format but cannot control the text source (for instance when displaying data loaded from the Web).

When the content is changed using any of these functions, any previous content is cleared.

By default, labels display \l{alignment}{left-aligned, vertically-centered} text and images, where any tabs in the text to be displayed are \l{Qt::TextExpandTabs}{automatically expanded}. However, the look of a QLabel can be adjusted and fine-tuned in several ways.

The positioning of the content within the QLabel widget area can be tuned with setAlignment() and setIndent(). Text content can also wrap lines along word boundaries with setWordWrap(). For example, this code sets up a sunken panel with a two-line text in the bottom right corner (both lines being flush with the right side of the label):

The properties and functions QLabel inherits from QFrame can also be used to specify the widget frame to be used for any given label.

A QLabel is often used as a label for an interactive widget. For this use QLabel provides a useful mechanism for adding an mnemonic (see QKeySequence) that will set the keyboard focus to the other widget (called the QLabel's "buddy"). For example:

In this example, keyboard focus is transferred to the label's buddy (the QLineEdit) when the user presses Alt+P. If the buddy was a button (inheriting from QAbstractButton), triggering the mnemonic would emulate a button click.

See also: QLineEdit, QTextEdit, QPixmap, QMovie

Definition at line 55 of file qlabel.h.

Constructor & Destructor Documentation

◆ QLabel() [1/2]

QLabel::QLabel	(	QWidget *	parent = `nullptr`,
		Qt::WindowFlags	f = `Qt::WindowFlags()`
	)

explicit

Constructs an empty label.

The parent and widget flag f, arguments are passed to the QFrame constructor.

See also: setAlignment(), setFrameStyle(), setIndent()

Definition at line 225 of file qlabel.cpp.

◆ QLabel() [2/2]

QLabel::QLabel	(	const QString &	text,
		QWidget *	parent = `nullptr`,
		Qt::WindowFlags	f = `Qt::WindowFlags()`
	)

explicit

Constructs a label that displays the text, text.

The parent and widget flag f, arguments are passed to the QFrame constructor.

See also: setText(), setAlignment(), setFrameStyle(), setIndent()

Definition at line 240 of file qlabel.cpp.

Here is the call graph for this function:

◆ ~QLabel()

QLabel::~QLabel ( )

Destroys the label.

Definition at line 252 of file qlabel.cpp.

Member Function Documentation

◆ alignment()

Qt::Alignment QLabel::alignment ( ) const

Definition at line 488 of file qlabel.cpp.

◆ buddy()

QWidget * QLabel::buddy ( ) const

Returns this label's buddy, or nullptr if no buddy is currently set.

See also: setBuddy()

Definition at line 1231 of file qlabel.cpp.

Here is the caller graph for this function:

◆ changeEvent()

void QLabel::changeEvent ( QEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QFrame.

Definition at line 1452 of file qlabel.cpp.

Here is the call graph for this function:

◆ clear

void QLabel::clear ( )

slot

Clears any label contents.

Definition at line 359 of file qlabel.cpp.

◆ contextMenuEvent()

void QLabel::contextMenuEvent ( QContextMenuEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Reimplemented in ContextMenuWidget.

Definition at line 918 of file qlabel.cpp.

Here is the call graph for this function:

◆ event()

bool QLabel::event ( QEvent * e )

overrideprotectedvirtual

\reimp

Reimplemented from QFrame.

Reimplemented in ContextMenuWidget.

Definition at line 990 of file qlabel.cpp.

Here is the call graph for this function:

◆ focusInEvent()

void QLabel::focusInEvent ( QFocusEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Definition at line 939 of file qlabel.cpp.

Here is the call graph for this function:

◆ focusNextPrevChild()

bool QLabel::focusNextPrevChild ( bool next )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Definition at line 972 of file qlabel.cpp.

Here is the call graph for this function:

◆ focusOutEvent()

void QLabel::focusOutEvent ( QFocusEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Definition at line 952 of file qlabel.cpp.

Here is the call graph for this function:

◆ hasScaledContents()

bool QLabel::hasScaledContents ( ) const

Definition at line 1479 of file qlabel.cpp.

◆ hasSelectedText()

bool QLabel::hasSelectedText ( ) const

Definition at line 801 of file qlabel.cpp.

◆ heightForWidth()

int QLabel::heightForWidth ( int w ) const

overridevirtual

\reimp

Reimplemented from QWidget.

Definition at line 684 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ indent()

int QLabel::indent ( ) const

Definition at line 551 of file qlabel.cpp.

◆ keyPressEvent()

void QLabel::keyPressEvent ( QKeyEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Definition at line 982 of file qlabel.cpp.

◆ linkActivated

void QLabel::linkActivated ( const QString & link )

signal

Since: 4.2

This signal is emitted when the user clicks a link. The URL referred to by the anchor is passed in link.

See also: linkHovered()

◆ linkHovered

void QLabel::linkHovered ( const QString & link )

signal

Since: 4.2

This signal is emitted when the user hovers over a link. The URL referred to by the anchor is passed in link.

See also: linkActivated()

◆ margin()

int QLabel::margin ( ) const

Definition at line 569 of file qlabel.cpp.

◆ minimumSizeHint()

QSize QLabel::minimumSizeHint ( ) const

overridevirtual

\reimp

Reimplemented from QWidget.

Definition at line 865 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ mouseMoveEvent()

void QLabel::mouseMoveEvent ( QMouseEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Reimplemented in MouseMonitor.

Definition at line 901 of file qlabel.cpp.

Here is the caller graph for this function:

◆ mousePressEvent()

void QLabel::mousePressEvent ( QMouseEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Reimplemented in DraggableLabel, MouseMonitor, and ClickableLabel.

Definition at line 893 of file qlabel.cpp.

Here is the caller graph for this function:

◆ mouseReleaseEvent()

void QLabel::mouseReleaseEvent ( QMouseEvent * ev )

overrideprotectedvirtual

\reimp

Reimplemented from QWidget.

Definition at line 909 of file qlabel.cpp.

◆ openExternalLinks()

bool QLabel::openExternalLinks ( ) const

Definition at line 707 of file qlabel.cpp.

◆ paintEvent()

void QLabel::paintEvent ( QPaintEvent * )

overrideprotectedvirtual

\reimp

Reimplemented from QFrame.

Definition at line 1035 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ picture()

QPicture QLabel::picture ( ) const

Deprecated:: Use the overload without argument instead.

Since: 5.15

Returns the label's picture.

Previously, Qt provided a version of picture() which returned the picture by-pointer. That version is now removed. This overload allowed to explicitly differentiate between the by-pointer function and the by-value.

Since: 6.0

Returns the label's picture.

Definition at line 207 of file qlabel.cpp.

◆ pixmap()

QPixmap QLabel::pixmap ( ) const

Definition at line 384 of file qlabel.cpp.

◆ resourceProvider()

QTextDocument::ResourceProvider QLabel::resourceProvider ( ) const

Since: 6.1

Returns the resource provider for rich text of this label.

Definition at line 1428 of file qlabel.cpp.

◆ selectedText()

QString QLabel::selectedText ( ) const

Definition at line 825 of file qlabel.cpp.

◆ selectionStart()

int QLabel::selectionStart ( ) const

selectionStart() returns the index of the first selected character in the label or -1 if no text is selected.

See also: selectedText()

{Note:} The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

Since: 4.7

Definition at line 844 of file qlabel.cpp.

◆ setAlignment()

void QLabel::setAlignment ( Qt::Alignment alignment )

Definition at line 476 of file qlabel.cpp.

Here is the caller graph for this function:

◆ setBuddy()

void QLabel::setBuddy ( QWidget * buddy )

Sets this label's buddy to buddy.

When the user presses the shortcut key indicated by this label, the keyboard focus is transferred to the label's buddy widget.

The buddy mechanism is only available for QLabels that contain text in which one character is prefixed with an ampersand, '&'. This character is set as the shortcut key. See the \l QKeySequence::mnemonic() documentation for details (to display an actual ampersand, use '&&').

In a dialog, you might create two data entry widgets and a label for each, and set up the geometry layout so each label is just to the left of its data entry widget (its "buddy"), for example:

With the code above, the focus jumps to the Name field when the user presses Alt+N, and to the Phone field when the user presses Alt+P.

To unset a previously set buddy, call this function with buddy set to nullptr.

See also: buddy(), setText(), QShortcut, setAlignment()

Definition at line 1201 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ setIndent()

void QLabel::setIndent ( int indent )

Definition at line 544 of file qlabel.cpp.

Here is the caller graph for this function:

◆ setMargin()

void QLabel::setMargin ( int margin )

Definition at line 575 of file qlabel.cpp.

Here is the caller graph for this function:

◆ setNum [1/2]

void QLabel::setNum ( double num )

slot

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

Sets the label contents to plain text containing the textual representation of double num. Any previous content is cleared. Does nothing if the double's string representation is the same as the current contents of the label.

The buddy shortcut, if any, is disabled.

See also: setText(), QString::setNum(), setBuddy()

Definition at line 460 of file qlabel.cpp.

Here is the call graph for this function:

◆ setNum [2/2]

void QLabel::setNum ( int num )

slot

Sets the label contents to plain text containing the textual representation of integer num. Any previous content is cleared. Does nothing if the integer's string representation is the same as the current contents of the label.

The buddy shortcut, if any, is disabled.

See also: setText(), QString::setNum(), setBuddy()

Definition at line 440 of file qlabel.cpp.

Here is the call graph for this function:

◆ setOpenExternalLinks()

void QLabel::setOpenExternalLinks ( bool open )

Definition at line 713 of file qlabel.cpp.

Here is the call graph for this function:

◆ setPicture

void QLabel::setPicture ( const QPicture & picture )

slot

Sets the label contents to picture. Any previous content is cleared.

The buddy shortcut, if any, is disabled.

See also: picture(), setBuddy()

Definition at line 419 of file qlabel.cpp.

◆ setPixmap

void QLabel::setPixmap ( const QPixmap & pixmap )

slot

Definition at line 373 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ setResourceProvider()

void QLabel::setResourceProvider ( const QTextDocument::ResourceProvider & provider )

Since: 6.1

Sets the provider of resources for rich text of this label.

Note: The label {does not} take ownership of the provider.

Definition at line 1441 of file qlabel.cpp.

◆ setScaledContents()

void QLabel::setScaledContents ( bool enable )

Definition at line 1485 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ setSelection()

void QLabel::setSelection	(	int	start,
		int	length
	)

Selects text from position start and for length characters.

See also: selectedText()

{Note:} The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

Since: 4.7

Definition at line 773 of file qlabel.cpp.

◆ setText

void QLabel::setText ( const QString & text )

slot

Definition at line 297 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ setTextFormat()

void QLabel::setTextFormat ( Qt::TextFormat format )

Definition at line 1410 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ setTextInteractionFlags()

void QLabel::setTextInteractionFlags ( Qt::TextInteractionFlags flags )

Definition at line 733 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ setWordWrap()

void QLabel::setWordWrap ( bool on )

Definition at line 506 of file qlabel.cpp.

Here is the caller graph for this function:

◆ sizeHint()

QSize QLabel::sizeHint ( ) const

overridevirtual

\reimp

Reimplemented from QFrame.

Definition at line 854 of file qlabel.cpp.

Here is the call graph for this function:

Here is the caller graph for this function:

◆ text()

QString QLabel::text ( ) const

Definition at line 349 of file qlabel.cpp.

Here is the caller graph for this function:

◆ textFormat()

Qt::TextFormat QLabel::textFormat ( ) const

Definition at line 1404 of file qlabel.cpp.

◆ textInteractionFlags()

Qt::TextInteractionFlags QLabel::textInteractionFlags ( ) const

Definition at line 757 of file qlabel.cpp.

◆ wordWrap()

bool QLabel::wordWrap ( ) const

Definition at line 517 of file qlabel.cpp.

Friends And Related Function Documentation

◆ QBalloonTip

friend class QBalloonTip

friend

Definition at line 180 of file qlabel.h.

◆ QMessageBoxPrivate

friend class QMessageBoxPrivate

friend

Definition at line 179 of file qlabel.h.

Property Documentation

◆ alignment

QLabel::alignment

readwrite

the alignment of the label's contents

By default, the contents of the label are left-aligned and vertically-centered.

See also: text

Definition at line 183 of file qlabel.h.

◆ hasSelectedText

QLabel::hasSelectedText

read

whether there is any text selected

hasSelectedText() returns true if some or all of the text has been selected by the user; otherwise returns false.

By default, this property is false.

See also: selectedText()

{Note:} The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

Since: 4.7

Definition at line 183 of file qlabel.h.

◆ indent

QLabel::indent

readwrite

the label's text indent in pixels

If a label displays text, the indent applies to the left edge if alignment() is Qt::AlignLeft, to the right edge if alignment() is Qt::AlignRight, to the top edge if alignment() is Qt::AlignTop, and to the bottom edge if alignment() is Qt::AlignBottom.

If indent is negative, or if no indent has been set, the label computes the effective indent as follows: If frameWidth() is 0, the effective indent becomes 0. If frameWidth() is greater than 0, the effective indent becomes half the width of the "x" character of the widget's current font().

By default, the indent is -1, meaning that an effective indent is calculating in the manner described above.

See also: alignment, margin, frameWidth(), font()

Definition at line 183 of file qlabel.h.

◆ margin

QLabel::margin

readwrite

the width of the margin

The margin is the distance between the innermost pixel of the frame and the outermost pixel of contents.

The default margin is 0.

See also: indent

Definition at line 183 of file qlabel.h.

◆ openExternalLinks

QLabel::openExternalLinks

readwrite

Since: 4.2

Specifies whether QLabel should automatically open links using QDesktopServices::openUrl() instead of emitting the linkActivated() signal.

{Note:} The textInteractionFlags set on the label need to include either LinksAccessibleByMouse or LinksAccessibleByKeyboard.

The default value is false.

See also: textInteractionFlags()

Definition at line 183 of file qlabel.h.

◆ pixmap

QLabel::pixmap

readwrite

the label's pixmap.

Setting the pixmap clears any previous content. The buddy shortcut, if any, is disabled.

Definition at line 183 of file qlabel.h.

◆ scaledContents

QLabel::scaledContents

readwrite

whether the label will scale its contents to fill all available space.

When enabled and the label shows a pixmap, it will scale the pixmap to fill the available space.

This property's default is false.

Definition at line 183 of file qlabel.h.

◆ selectedText

QLabel::selectedText

read

the selected text

If there is no selected text this property's value is an empty string.

By default, this property contains an empty string.

See also: hasSelectedText()

{Note:} The textInteractionFlags set on the label need to include either TextSelectableByMouse or TextSelectableByKeyboard.

Since: 4.7

Definition at line 183 of file qlabel.h.

◆ text

QLabel::text

readwrite

the label's text

If no text has been set this will return an empty string. Setting the text clears any previous content.

The text will be interpreted either as plain text or as rich text, depending on the text format setting; see setTextFormat(). The default setting is Qt::AutoText; i.e. QLabel will try to auto-detect the format of the text set. See \l {Supported HTML Subset} for the definition of rich text.

If a buddy has been set, the buddy mnemonic key is updated from the new text.

Note that QLabel is well-suited to display small rich text documents, such as small documents that get their document specific settings (font, text color, link color) from the label's palette and font properties. For large documents, use QTextEdit in read-only mode instead. QTextEdit can also provide a scroll bar when necessary.

Note: This function enables mouse tracking if text contains rich text.

See also: setTextFormat(), setBuddy(), alignment

Definition at line 183 of file qlabel.h.

◆ textFormat

QLabel::textFormat

readwrite

the label's text format

See the Qt::TextFormat enum for an explanation of the possible options.

The default format is Qt::AutoText.

See also: text()

Definition at line 183 of file qlabel.h.

◆ textInteractionFlags

QLabel::textInteractionFlags

readwrite

Since: 4.2

Specifies how the label should interact with user input if it displays text.

If the flags contain Qt::LinksAccessibleByKeyboard the focus policy is also automatically set to Qt::StrongFocus. If Qt::TextSelectableByKeyboard is set then the focus policy is set to Qt::ClickFocus.

The default value is Qt::LinksAccessibleByMouse.

Definition at line 183 of file qlabel.h.

◆ wordWrap

QLabel::wordWrap

readwrite

the label's word-wrapping policy

If this property is true then label text is wrapped where necessary at word-breaks; otherwise it is not wrapped at all.

By default, word wrap is disabled.

See also: text

Definition at line 183 of file qlabel.h.

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

src/widgets/widgets/qlabel.h
src/widgets/widgets/qlabel.cpp

Public Slots

Signals

Public Member Functions

Protected Member Functions

Properties

Friends

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QLabel() [1/2]

◆ QLabel() [2/2]

◆ ~QLabel()

Member Function Documentation

◆ alignment()

◆ buddy()

◆ changeEvent()

◆ clear

◆ contextMenuEvent()

◆ event()

◆ focusInEvent()

◆ focusNextPrevChild()

◆ focusOutEvent()

◆ hasScaledContents()

◆ hasSelectedText()

◆ heightForWidth()

◆ indent()

◆ keyPressEvent()

◆ linkActivated

◆ linkHovered

◆ margin()

◆ minimumSizeHint()

◆ mouseMoveEvent()

◆ mousePressEvent()

◆ mouseReleaseEvent()

◆ openExternalLinks()

◆ paintEvent()

◆ picture()

◆ pixmap()

◆ resourceProvider()

◆ selectedText()

◆ selectionStart()

◆ setAlignment()

◆ setBuddy()

◆ setIndent()

◆ setMargin()

◆ setNum [1/2]

◆ setNum [2/2]

◆ setOpenExternalLinks()

◆ setPicture

◆ setPixmap

◆ setResourceProvider()

◆ setScaledContents()

◆ setSelection()

◆ setText

◆ setTextFormat()

◆ setTextInteractionFlags()

◆ setWordWrap()

◆ sizeHint()

◆ text()

◆ textFormat()

◆ textInteractionFlags()

◆ wordWrap()

Friends And Related Function Documentation

◆ QBalloonTip

◆ QMessageBoxPrivate

Property Documentation

◆ alignment

◆ hasSelectedText

◆ indent

◆ margin

◆ openExternalLinks

◆ pixmap

◆ scaledContents

◆ selectedText

◆ text

◆ textFormat

◆ textInteractionFlags

◆ wordWrap