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39
40#ifndef QPAINTDEVICEWINDOW_P_H
41#define QPAINTDEVICEWINDOW_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtGui/private/qtguiglobal_p.h>
55#include <QtGui/QPaintDeviceWindow>
56#include <QtCore/QCoreApplication>
57#include <QtGui/private/qwindow_p.h>
58#include <QtGui/QPaintEvent>
59
60QT_BEGIN_NAMESPACE
61
62class Q_GUI_EXPORT QPaintDeviceWindowPrivate : public QWindowPrivate
63{
64 Q_DECLARE_PUBLIC(QPaintDeviceWindow)
65
66public:
67 virtual void beginPaint(const QRegion &region)
68 {
69 Q_UNUSED(region);
70 }
71
72 virtual void endPaint()
73 {
74 }
75
76 virtual void flush(const QRegion &region)
77 {
78 Q_UNUSED(region);
79 }
80
81 bool paint(const QRegion &region)
82 {
83 Q_Q(QPaintDeviceWindow);
84 QRegion toPaint = region & dirtyRegion;
85 if (toPaint.isEmpty())
86 return false;
87
88 // Clear the region now. The overridden functions may call update().
89 dirtyRegion -= toPaint;
90
91 beginPaint(region: toPaint);
92
93 QPaintEvent paintEvent(toPaint);
94 q->paintEvent(event: &paintEvent);
95
96 endPaint();
97
98 return true;
99 }
100
101 void doFlush(const QRegion &region)
102 {
103 QRegion toFlush = region;
104 if (paint(region: toFlush))
105 flush(region: toFlush);
106 }
107
108 void handleUpdateEvent()
109 {
110 if (dirtyRegion.isEmpty())
111 return;
112 doFlush(region: dirtyRegion);
113 }
114
115 void markWindowAsDirty()
116 {
117 Q_Q(QPaintDeviceWindow);
118 dirtyRegion += QRect(QPoint(0, 0), q->size());
119 }
120
121private:
122 QRegion dirtyRegion;
123};
124
125
126QT_END_NAMESPACE
127
128#endif //QPAINTDEVICEWINDOW_P_H
129

source code of qtbase/src/gui/kernel/qpaintdevicewindow_p.h