QBackingStore ¶

概要 ¶

详细描述 ¶

QBackingStore enables the use of QPainter to paint on a QWindow with type RasterSurface. The other way of rendering to a QWindow is through the use of OpenGL with QOpenGLContext .

A QBackingStore contains a buffered representation of the window contents, and thus supports partial updates by using QPainter to only update a sub region of the window contents.

QBackingStore might be used by an application that wants to use QPainter without OpenGL acceleration and without the extra overhead of using the QWidget or QGraphicsView UI stacks. For an example of how to use QBackingStore see the 光栅窗口范例 .

class QBackingStore ( window ) ¶

param window

QWindow

Constructs an empty surface for the given top-level window .

PySide2.QtGui.QBackingStore. beginPaint ( arg__1 ) ¶

参数

arg__1 – QRegion

Begins painting on the backing store surface in the given region .

You should call this function before using the paintDevice() to paint.

另请参阅

endPaint() paintDevice()

PySide2.QtGui.QBackingStore. endPaint ( ) ¶

Ends painting.

You should call this function after painting with the paintDevice() has ended.

另请参阅

beginPaint() paintDevice()

PySide2.QtGui.QBackingStore. flush ( region [ , window=None [ , offset=QPoint() ] ] ) ¶

参数

• region – QRegion

• window – QWindow

• offset – QPoint

Flushes the given region from the specified window onto the screen.

window must either be the top level window represented by this backingstore, or a non-transient child of that window. Passing None falls back to using the backingstore’s top level window.

若 window is a child window, the region should be in child window coordinates, and the offset should be the child window’s offset in relation to the backingstore’s top level window.

You should call this function after ending painting with endPaint() .

PySide2.QtGui.QBackingStore. hasStaticContents ( ) ¶

返回类型

bool

Returns a boolean indicating if this window has static contents or not.

PySide2.QtGui.QBackingStore. paintDevice ( ) ¶

返回类型

QPaintDevice

Returns the paint device for this surface.

警告

The device is only valid between calls to beginPaint() and endPaint() . You should not cache the returned value.

PySide2.QtGui.QBackingStore. resize ( size ) ¶

参数

size – QSize

Sets the size of the window surface to size .

另请参阅

size()

PySide2.QtGui.QBackingStore. scroll ( area , dx , dy ) ¶

参数

• area – QRegion

• dx – int

• dy – int

返回类型

bool

Scrolls the given area dx 像素到右侧和 dy downward; both dx and dy 可能为负值。

返回 true if the area was scrolled successfully; false otherwise.

PySide2.QtGui.QBackingStore. setStaticContents ( region ) ¶

参数

region – QRegion

Set region as the static contents of this window.

另请参阅

staticContents()

PySide2.QtGui.QBackingStore. size ( ) ¶

返回类型

QSize

Returns the current size of the window surface.

PySide2.QtGui.QBackingStore. staticContents ( ) ¶

返回类型

QRegion

返回 QRegion representing the area of the window that has static contents.

另请参阅

setStaticContents()

PySide2.QtGui.QBackingStore. window ( ) ¶

返回类型

QWindow

Returns a pointer to the top-level window associated with this surface.