QScreen Class Reference

The QScreen class is used to query screen properties. \inmodule QtGui. More...

#include <qscreen.h>

Inheritance diagram for QScreen:

Collaboration diagram for QScreen:

Signals
void	geometryChanged (const QRect &geometry)
void	availableGeometryChanged (const QRect &geometry)
void	physicalSizeChanged (const QSizeF &size)
void	physicalDotsPerInchChanged (qreal dpi)
void	logicalDotsPerInchChanged (qreal dpi)
void	virtualGeometryChanged (const QRect &rect)
void	primaryOrientationChanged (Qt::ScreenOrientation orientation)
	This signal is emitted when the primary orientation of the screen changes with orientation as an argument.
void	orientationChanged (Qt::ScreenOrientation orientation)
	This signal is emitted when the orientation of the screen changes with orientation as an argument.
void	refreshRateChanged (qreal refreshRate)
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.

Public Member Functions
	~QScreen ()
	Destroys the screen.
QPlatformScreen *	handle () const
	Get the platform screen handle.
QString	name () const
QString	manufacturer () const
QString	model () const
QString	serialNumber () const
int	depth () const
QSize	size () const
QRect	geometry () const
QSizeF	physicalSize () const
qreal	physicalDotsPerInchX () const
qreal	physicalDotsPerInchY () const
qreal	physicalDotsPerInch () const
qreal	logicalDotsPerInchX () const
qreal	logicalDotsPerInchY () const
qreal	logicalDotsPerInch () const
qreal	devicePixelRatio () const
QSize	availableSize () const
QRect	availableGeometry () const
QList< QScreen * >	virtualSiblings () const
	Get the screen's virtual siblings.
QScreen *	virtualSiblingAt (QPoint point)
	Returns the screen at point within the set of \l QScreen::virtualSiblings(), or nullptr if outside of any screen.
QSize	virtualSize () const
QRect	virtualGeometry () const
QSize	availableVirtualSize () const
QRect	availableVirtualGeometry () const
Qt::ScreenOrientation	primaryOrientation () const
Qt::ScreenOrientation	orientation () const
Qt::ScreenOrientation	nativeOrientation () const
int	angleBetween (Qt::ScreenOrientation a, Qt::ScreenOrientation b) const
	Convenience function to compute the angle of rotation to get from rotation a to rotation b.
QTransform	transformBetween (Qt::ScreenOrientation a, Qt::ScreenOrientation b, const QRect &target) const
	Convenience function to compute a transform that maps from the coordinate system defined by orientation a into the coordinate system defined by orientation b and target dimensions target.
QRect	mapBetween (Qt::ScreenOrientation a, Qt::ScreenOrientation b, const QRect &rect) const
	Maps the rect between two screen orientations.
bool	isPortrait (Qt::ScreenOrientation orientation) const
	Convenience function that returns true if o is either portrait or inverted portrait; otherwise returns false.
bool	isLandscape (Qt::ScreenOrientation orientation) const
	Convenience function that returns true if o is either landscape or inverted landscape; otherwise returns false.
QPixmap	grabWindow (WId window=0, int x=0, int y=0, int w=-1, int h=-1)
	Creates and returns a pixmap constructed by grabbing the contents of the given window restricted by QRect(x, y, width, height).
qreal	refreshRate () const
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.
bool	moveToThread (QThread *thread QT6_DECL_NEW_OVERLOAD_TAIL)
	Changes the thread affinity for this object and its children and returns true on success.
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::nanoseconds time, Qt::TimerType timerType=Qt::CoarseTimer)
void	killTimer (int id)
	Kills the timer with timer identifier, id.
void	killTimer (Qt::TimerId id)
template<typename T >
T	findChild (QAnyStringView aName, 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 (QAnyStringView 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 >
T	findChild (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.
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.

Properties
QString	name
	a user presentable string representing the screen
QString	manufacturer
	the manufacturer of the screen
QString	model
	the model of the screen
QString	serialNumber
	the serial number of the screen
int	depth
	the color depth of the screen
QSize	size
	the pixel resolution of the screen
QSize	availableSize
	the screen's available size in pixels
QSize	virtualSize
	the pixel size of the virtual desktop to which this screen belongs
QSize	availableVirtualSize
	the available size of the virtual desktop to which this screen belongs
QRect	geometry
	the screen's geometry in pixels
QRect	availableGeometry
	the screen's available geometry in pixels
QRect	virtualGeometry
	the pixel geometry of the virtual desktop to which this screen belongs
QRect	availableVirtualGeometry
	the available geometry of the virtual desktop to which this screen belongs
QSizeF	physicalSize
	the screen's physical size (in millimeters)
qreal	physicalDotsPerInchX
	the number of physical dots or pixels per inch in the horizontal direction
qreal	physicalDotsPerInchY
	the number of physical dots or pixels per inch in the vertical direction
qreal	physicalDotsPerInch
	the number of physical dots or pixels per inch
qreal	logicalDotsPerInchX
	the number of logical dots or pixels per inch in the horizontal direction
qreal	logicalDotsPerInchY
	the number of logical dots or pixels per inch in the vertical direction
qreal	logicalDotsPerInch
	the number of logical dots or pixels per inch
qreal	devicePixelRatio
	the screen's ratio between physical pixels and device-independent pixels
Qt::ScreenOrientation	primaryOrientation
	the primary screen orientation
Qt::ScreenOrientation	orientation
	the screen orientation
Qt::ScreenOrientation	nativeOrientation
	the native screen orientation
qreal	refreshRate
	the approximate vertical refresh rate of the screen in Hz
Properties inherited from QObject
QString	objectName
	the name of this object

Friends
class	QGuiApplicationPrivate
class	QPlatformIntegration
class	QPlatformScreen
class	QHighDpiScaling
class	QWindowSystemInterface

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe
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 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
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 QScreen class is used to query screen properties. \inmodule QtGui.

Since

5.0

A note on logical vs physical dots per inch: physical DPI is based on the actual physical pixel sizes when available, and is useful for print preview and other cases where it's desirable to know the exact physical dimensions of screen displayed contents.

Logical dots per inch are used to convert font and user interface elements from point sizes to pixel sizes, and might be different from the physical dots per inch. The logical dots per inch are sometimes user-settable in the desktop environment's settings panel, to let the user globally control UI and font sizes in different applications.

Note

Both physical and logical DPI are expressed in device-independent dots. Multiply by QScreen::devicePixelRatio() to get device-dependent density.

\inmodule QtGui

Definition at line 31 of file qscreen.h.

Constructor & Destructor Documentation

~QScreen()

QScreen::~QScreen

(

)

Destroys the screen.

Definition at line 73 of file qscreen.cpp.

Member Function Documentation

angleBetween()

int QScreen::angleBetween	(	Qt::ScreenOrientation	a,
		Qt::ScreenOrientation	b ) const

Convenience function to compute the angle of rotation to get from rotation a to rotation b.

The result will be 0, 90, 180, or 270.

Qt::PrimaryOrientation is interpreted as the screen's primaryOrientation().

Definition at line 520 of file qscreen.cpp.

availableGeometry()

QRect QScreen::availableGeometry

(

)

const

Definition at line 345 of file qscreen.cpp.

availableGeometryChanged

void QScreen::availableGeometryChanged ( const QRect & geometry )

signal

availableSize()

QSize QScreen::availableSize

(

)

const

Definition at line 315 of file qscreen.cpp.

availableVirtualGeometry()

QRect QScreen::availableVirtualGeometry

(

)

const

Definition at line 431 of file qscreen.cpp.

availableVirtualSize()

QSize QScreen::availableVirtualSize

(

)

const

Definition at line 416 of file qscreen.cpp.

depth()

int QScreen::depth

(

)

const

Definition at line 147 of file qscreen.cpp.

devicePixelRatio()

qreal QScreen::devicePixelRatio

(

)

const

Definition at line 286 of file qscreen.cpp.

geometry()

QRect QScreen::geometry

(

)

const

Definition at line 328 of file qscreen.cpp.

geometryChanged

void QScreen::geometryChanged ( const QRect & geometry )

signal

grabWindow()

QPixmap QScreen::grabWindow	(	WId	window = 0,
		int	x = 0,
		int	y = 0,
		int	width = -1,
		int	height = -1 )

Creates and returns a pixmap constructed by grabbing the contents of the given window restricted by QRect(x, y, width, height).

If window is 0, then the entire screen will be grabbed.

The arguments ({x}, {y}) specify the offset in the window, whereas ({width}, {height}) specify the area to be copied. If width is negative, the function copies everything to the right border of the window. If height is negative, the function copies everything to the bottom of the window.

The offset and size arguments are specified in device independent pixels. The returned pixmap may be larger than the requested size when grabbing from a high-DPI screen. Call QPixmap::devicePixelRatio() to determine if this is the case.

The window system identifier (WId) can be retrieved using the QWidget::winId() function. The rationale for using a window identifier and not a QWidget, is to enable grabbing of windows that are not part of the application, window system frames, and so on.

Warning

Grabbing windows that are not part of the application is not supported on systems such as iOS, where sandboxing/security prevents reading pixels of windows not owned by the application.

The grabWindow() function grabs pixels from the screen, not from the window, i.e. if there is another window partially or entirely over the one you grab, you get pixels from the overlying window, too. The mouse cursor is generally not grabbed.

Note on X11 that if the given window doesn't have the same depth as the root window, and another window partially or entirely obscures the one you grab, you will not get pixels from the overlying window. The contents of the obscured areas in the pixmap will be undefined and uninitialized.

On Windows Vista and above grabbing a layered window, which is created by setting the Qt::WA_TranslucentBackground attribute, will not work. Instead grabbing the desktop widget should work.

Warning

In general, grabbing an area outside the screen is not safe. This depends on the underlying window system.

Definition at line 686 of file qscreen.cpp.

handle()

QPlatformScreen * QScreen::handle

(

)

const

Get the platform screen handle.

See also

{Qt Platform Abstraction}{Qt Platform Abstraction (QPA)}

Definition at line 84 of file qscreen.cpp.

isLandscape()

bool QScreen::isLandscape

(

Qt::ScreenOrientation

o

)

const

Convenience function that returns true if o is either landscape or inverted landscape; otherwise returns false.

Qt::PrimaryOrientation is interpreted as the screen's primaryOrientation().

Definition at line 592 of file qscreen.cpp.

isPortrait()

bool QScreen::isPortrait

(

Qt::ScreenOrientation

o

)

const

Convenience function that returns true if o is either portrait or inverted portrait; otherwise returns false.

Qt::PrimaryOrientation is interpreted as the screen's primaryOrientation().

Definition at line 580 of file qscreen.cpp.

logicalDotsPerInch()

qreal QScreen::logicalDotsPerInch

(

)

const

Definition at line 267 of file qscreen.cpp.

logicalDotsPerInchChanged

void QScreen::logicalDotsPerInchChanged ( qreal dpi )

signal

logicalDotsPerInchX()

qreal QScreen::logicalDotsPerInchX

(

)

const

Definition at line 231 of file qscreen.cpp.

logicalDotsPerInchY()

qreal QScreen::logicalDotsPerInchY

(

)

const

Definition at line 247 of file qscreen.cpp.

manufacturer()

QString QScreen::manufacturer

(

)

const

Definition at line 113 of file qscreen.cpp.

mapBetween()

QRect QScreen::mapBetween	(	Qt::ScreenOrientation	a,
		Qt::ScreenOrientation	b,
		const QRect &	rect ) const

Maps the rect between two screen orientations.

This will flip the x and y dimensions of the rectangle {rect} if the orientation {a} is Qt::PortraitOrientation or Qt::InvertedPortraitOrientation and orientation {b} is Qt::LandscapeOrientation or Qt::InvertedLandscapeOrientation, or vice versa.

Qt::PrimaryOrientation is interpreted as the screen's primaryOrientation().

Definition at line 563 of file qscreen.cpp.

model()

QString QScreen::model

(

)

const

Definition at line 125 of file qscreen.cpp.

name()

QString QScreen::name

(

)

const

Definition at line 101 of file qscreen.cpp.

Referenced by testing.tools.encode_pdf_filter._PdfStream::RegisterByName().

Here is the caller graph for this function:

nativeOrientation()

Qt::ScreenOrientation QScreen::nativeOrientation

(

)

const

Definition at line 506 of file qscreen.cpp.

orientation()

Qt::ScreenOrientation QScreen::orientation

(

)

const

Definition at line 455 of file qscreen.cpp.

orientationChanged

void QScreen::orientationChanged ( Qt::ScreenOrientation orientation )

signal

This signal is emitted when the orientation of the screen changes with orientation as an argument.

See also

orientation()

physicalDotsPerInch()

qreal QScreen::physicalDotsPerInch

(

)

const

Definition at line 216 of file qscreen.cpp.

physicalDotsPerInchChanged

void QScreen::physicalDotsPerInchChanged ( qreal dpi )

signal

physicalDotsPerInchX()

qreal QScreen::physicalDotsPerInchX

(

)

const

Definition at line 176 of file qscreen.cpp.

physicalDotsPerInchY()

qreal QScreen::physicalDotsPerInchY

(

)

const

Definition at line 194 of file qscreen.cpp.

physicalSize()

QSizeF QScreen::physicalSize

(

)

const

Definition at line 302 of file qscreen.cpp.

physicalSizeChanged

void QScreen::physicalSizeChanged ( const QSizeF & size )

signal

primaryOrientation()

Qt::ScreenOrientation QScreen::primaryOrientation

(

)

const

Definition at line 489 of file qscreen.cpp.

primaryOrientationChanged

void QScreen::primaryOrientationChanged ( Qt::ScreenOrientation orientation )

signal

This signal is emitted when the primary orientation of the screen changes with orientation as an argument.

See also

primaryOrientation()

refreshRate()

qreal QScreen::refreshRate

(

)

const

Definition at line 470 of file qscreen.cpp.

refreshRateChanged

void QScreen::refreshRateChanged ( qreal refreshRate )

signal

serialNumber()

QString QScreen::serialNumber

(

)

const

Definition at line 137 of file qscreen.cpp.

size()

QSize QScreen::size

(

)

const

Definition at line 157 of file qscreen.cpp.

transformBetween()

QTransform QScreen::transformBetween	(	Qt::ScreenOrientation	a,
		Qt::ScreenOrientation	b,
		const QRect &	target ) const

Convenience function to compute a transform that maps from the coordinate system defined by orientation a into the coordinate system defined by orientation b and target dimensions target.

Example, a is Qt::Landscape, b is Qt::Portrait, and target is QRect(0, 0, w, h) the resulting transform will be such that the point QPoint(0, 0) is mapped to QPoint(0, w), and QPoint(h, w) is mapped to QPoint(0, h). Thus, the landscape coordinate system QRect(0, 0, h, w) is mapped (with a 90 degree rotation) into the portrait coordinate system QRect(0, 0, w, h).

Qt::PrimaryOrientation is interpreted as the screen's primaryOrientation().

Definition at line 543 of file qscreen.cpp.

virtualGeometry()

QRect QScreen::virtualGeometry

(

)

const

Definition at line 397 of file qscreen.cpp.

virtualGeometryChanged

void QScreen::virtualGeometryChanged ( const QRect & rect )

signal

virtualSiblingAt()

QScreen * QScreen::virtualSiblingAt

(

QPoint

point

)

Returns the screen at point within the set of \l QScreen::virtualSiblings(), or nullptr if outside of any screen.

The point is in relation to the virtualGeometry() of each set of virtual siblings.

Since

5.15

Definition at line 630 of file qscreen.cpp.

virtualSiblings()

QList< QScreen * > QScreen::virtualSiblings

(

)

const

Get the screen's virtual siblings.

The virtual siblings are the screen instances sharing the same virtual desktop. They share a common coordinate system, and windows can freely be moved or positioned across them without having to be re-created.

Definition at line 358 of file qscreen.cpp.

virtualSize()

QSize QScreen::virtualSize

(

)

const

Definition at line 382 of file qscreen.cpp.

Friends And Related Symbol Documentation

QGuiApplicationPrivate

friend class QGuiApplicationPrivate

friend

Definition at line 137 of file qscreen.h.

QHighDpiScaling

friend class QHighDpiScaling

friend

Definition at line 140 of file qscreen.h.

QPlatformIntegration

friend class QPlatformIntegration

friend

Definition at line 138 of file qscreen.h.

QPlatformScreen

friend class QPlatformScreen

friend

Definition at line 139 of file qscreen.h.

QWindowSystemInterface

friend class QWindowSystemInterface

friend

Definition at line 141 of file qscreen.h.

Property Documentation

availableGeometry

QRect QScreen::availableGeometry

read

the screen's available geometry in pixels

The available geometry is the geometry excluding window manager reserved areas such as task bars and system menus.

Note, on X11 this will return the true available geometry only on systems with one monitor and if window manager has set _NET_WORKAREA atom. In all other cases this is equal to geometry(). This is a limitation in X11 window manager specification.

Definition at line 46 of file qscreen.h.

availableSize

QSize QScreen::availableSize

read

the screen's available size in pixels

The available size is the size excluding window manager reserved areas such as task bars and system menus.

Definition at line 42 of file qscreen.h.

availableVirtualGeometry

QRect QScreen::availableVirtualGeometry

read

the available geometry of the virtual desktop to which this screen belongs

Returns the available geometry of the virtual desktop corresponding to this screen.

This is the union of the virtual siblings' individual available geometries.

See also

availableGeometry(), virtualSiblings()

Definition at line 48 of file qscreen.h.

availableVirtualSize

QSize QScreen::availableVirtualSize

read

the available size of the virtual desktop to which this screen belongs

Returns the available pixel size of the virtual desktop corresponding to this screen.

This is the combined size of the virtual siblings' individual available geometries.

See also

availableSize(), virtualSiblings()

Definition at line 44 of file qscreen.h.

depth

int QScreen::depth

read

the color depth of the screen

Definition at line 40 of file qscreen.h.

devicePixelRatio

qreal QScreen::devicePixelRatio

read

the screen's ratio between physical pixels and device-independent pixels

Since

5.5

Returns the ratio between physical pixels and device-independent pixels for the screen.

Common values are 1.0 on normal displays and 2.0 on "retina" displays. Higher values are also possible.

See also

QWindow::devicePixelRatio(), QGuiApplication::devicePixelRatio()

Definition at line 59 of file qscreen.h.

geometry

QRect QScreen::geometry

read

the screen's geometry in pixels

As an example this might return QRect(0, 0, 1280, 1024), or in a virtual desktop setting QRect(1280, 0, 1280, 1024).

Definition at line 45 of file qscreen.h.

logicalDotsPerInch

qreal QScreen::logicalDotsPerInch

read

the number of logical dots or pixels per inch

This value can be used to convert font point sizes to pixel sizes.

This is a convenience property that's simply the average of the logicalDotsPerInchX and logicalDotsPerInchY properties.

See also

logicalDotsPerInchX()

logicalDotsPerInchY()

Definition at line 58 of file qscreen.h.

logicalDotsPerInchX

qreal QScreen::logicalDotsPerInchX

read

the number of logical dots or pixels per inch in the horizontal direction

This value is used to convert font point sizes to pixel sizes.

See also

logicalDotsPerInchY()

Definition at line 56 of file qscreen.h.

logicalDotsPerInchY

qreal QScreen::logicalDotsPerInchY

read

the number of logical dots or pixels per inch in the vertical direction

This value is used to convert font point sizes to pixel sizes.

See also

logicalDotsPerInchX()

Definition at line 57 of file qscreen.h.

manufacturer

QString QScreen::manufacturer

read

the manufacturer of the screen

Since

5.9

Definition at line 37 of file qscreen.h.

model

QString QScreen::model

read

the model of the screen

Since

5.9

Definition at line 38 of file qscreen.h.

name

QString QScreen::name

read

a user presentable string representing the screen

For example, on X11 these correspond to the XRandr screen names, typically "VGA1", "HDMI1", etc.

Note

The user presentable string is not guaranteed to match the result of any native APIs, and should not be used to uniquely identify a screen.

Definition at line 36 of file qscreen.h.

Referenced by testing.tools.encode_pdf_filter._PdfStream::RegisterByName().

nativeOrientation

Qt::ScreenOrientation QScreen::nativeOrientation

read

the native screen orientation

Since

5.2

The native orientation of the screen is the orientation where the logo sticker of the device appears the right way up, or Qt::PrimaryOrientation if the platform does not support this functionality.

The native orientation is a property of the hardware, and does not change.

Definition at line 63 of file qscreen.h.

orientation

Qt::ScreenOrientation QScreen::orientation

read

the screen orientation

The orientation property tells the orientation of the screen from the window system perspective.

Most mobile devices and tablet computers contain accelerometer sensors. The Qt Sensors module provides the ability to read this sensor directly. However, the windowing system may rotate the entire screen automatically based on how it is being held; in that case, this orientation property will change.

See also

primaryOrientation(), QWindow::contentOrientation()

Definition at line 62 of file qscreen.h.

physicalDotsPerInch

qreal QScreen::physicalDotsPerInch

read

the number of physical dots or pixels per inch

This value represents the pixel density on the screen's display. Depending on what information the underlying system provides the value might not be entirely accurate.

This is a convenience property that's simply the average of the physicalDotsPerInchX and physicalDotsPerInchY properties.

Note

Physical DPI is expressed in device-independent dots. Multiply by QScreen::devicePixelRatio() to get device-dependent density.

See also

physicalDotsPerInchX()

physicalDotsPerInchY()

Definition at line 55 of file qscreen.h.

physicalDotsPerInchX

qreal QScreen::physicalDotsPerInchX

read

the number of physical dots or pixels per inch in the horizontal direction

This value represents the actual horizontal pixel density on the screen's display. Depending on what information the underlying system provides the value might not be entirely accurate.

Note

Physical DPI is expressed in device-independent dots. Multiply by QScreen::devicePixelRatio() to get device-dependent density.

See also

physicalDotsPerInchY()

Definition at line 51 of file qscreen.h.

physicalDotsPerInchY

qreal QScreen::physicalDotsPerInchY

read

the number of physical dots or pixels per inch in the vertical direction

This value represents the actual vertical pixel density on the screen's display. Depending on what information the underlying system provides the value might not be entirely accurate.

Note

Physical DPI is expressed in device-independent dots. Multiply by QScreen::devicePixelRatio() to get device-dependent density.

See also

physicalDotsPerInchX()

Definition at line 53 of file qscreen.h.

physicalSize

QSizeF QScreen::physicalSize

read

the screen's physical size (in millimeters)

The physical size represents the actual physical dimensions of the screen's display.

Depending on what information the underlying system provides the value might not be entirely accurate.

Definition at line 50 of file qscreen.h.

primaryOrientation

Qt::ScreenOrientation QScreen::primaryOrientation

read

the primary screen orientation

The primary screen orientation is Qt::LandscapeOrientation if the screen geometry's width is greater than or equal to its height, or Qt::PortraitOrientation otherwise. This property might change when the screen orientation was changed (i.e. when the display is rotated). The behavior is however platform dependent and can often be specified in an application manifest file.

Definition at line 60 of file qscreen.h.

refreshRate

qreal QScreen::refreshRate

read

the approximate vertical refresh rate of the screen in Hz

Warning

Avoid using the screen's refresh rate to drive animations via a timer such as QChronoTimer. Instead use QWindow::requestUpdate().

See also

QWindow::requestUpdate()

Definition at line 64 of file qscreen.h.

serialNumber

QString QScreen::serialNumber

read

the serial number of the screen

Since

5.9

Definition at line 39 of file qscreen.h.

size

QSize QScreen::size

read

the pixel resolution of the screen

Definition at line 41 of file qscreen.h.

virtualGeometry

QRect QScreen::virtualGeometry

read

the pixel geometry of the virtual desktop to which this screen belongs

Returns the pixel geometry of the virtual desktop corresponding to this screen.

This is the union of the virtual siblings' individual geometries.

See also

virtualSiblings()

Definition at line 47 of file qscreen.h.

virtualSize

QSize QScreen::virtualSize

read

the pixel size of the virtual desktop to which this screen belongs

Returns the pixel size of the virtual desktop corresponding to this screen.

This is the combined size of the virtual siblings' individual geometries.

See also

virtualSiblings()

Definition at line 43 of file qscreen.h.

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

• qtbase/src/gui/kernel/qscreen.h (706dafe347528dbcbaaf3b4d75fa78bd633d876b)
• qtbase/src/gui/kernel/qscreen.cpp (a0f53ec9708dd8032b466b868883f8118ab7c7ef)