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QPaintDeviceWindow Class

Convenience subclass of QWindow that is also a QPaintDevice. More...

Header: #include <QPaintDeviceWindow>
CMake: find_package(Qt6 REQUIRED COMPONENTS Gui)
target_link_libraries(mytarget PRIVATE Qt6::Gui)
qmake: QT += gui
Inherits: QWindow and QPaintDevice
Inherited By:

QOpenGLWindow and QRasterWindow

Public Functions

void update(const QRect &rect)
void update(const QRegion &region)

Public Slots

void update()

Reimplemented Protected Functions

virtual void paintEvent(QPaintEvent *event) override

Detailed Description

QPaintDeviceWindow is like a regular QWindow, with the added functionality of being a paint device too. Whenever the content needs to be updated, the virtual paintEvent() function is called. Subclasses, that reimplement this function, can then simply open a QPainter on the window.

Note: This class cannot directly be used in applications. It rather serves as a base for subclasses like QOpenGLWindow.

See also QOpenGLWindow.

Member Function Documentation

[override virtual protected] void QPaintDeviceWindow::paintEvent(QPaintEvent *event)

Reimplements: QWindow::paintEvent(QPaintEvent *ev).

Handles paint events passed in the event parameter.

The default implementation does nothing. Reimplement this function to perform painting. If necessary, the dirty area is retrievable from the event.

[slot] void QPaintDeviceWindow::update()

Marks the entire window as dirty and schedules a repaint.

Note: Subsequent calls to this function before the next paint event will get ignored.

Note: For non-exposed windows the update is deferred until the window becomes exposed again.

void QPaintDeviceWindow::update(const QRect &rect)

Marks the rect of the window as dirty and schedules a repaint.

Note: Subsequent calls to this function before the next paint event will get ignored, but rect is added to the region to update.

Note: For non-exposed windows the update is deferred until the window becomes exposed again.

void QPaintDeviceWindow::update(const QRegion &region)

Marks the region of the window as dirty and schedules a repaint.

Note: Subsequent calls to this function before the next paint event will get ignored, but region is added to the region to update.

Note: For non-exposed windows the update is deferred until the window becomes exposed again.

© The Qt Company Ltd
Licensed under the GNU Free Documentation License, Version 1.3.
https://doc.qt.io/qt-6.9/qpaintdevicewindow.html