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| |
| #include <QtGui> |
| #include <QtX11Extras/QX11Info> |
| |
| class IntensivePainter : public QWindow |
| { |
| public: |
| IntensivePainter() : m_backingStore(new QBackingStore(this)) |
| { setGeometry(100, 100, 900, 600); } |
| |
| protected: |
| bool interrupted() const { return m_stopPainting; } |
| void stopPainting() { m_stopPainting = true; } |
| void beginPaining() { m_stopPainting = false; } |
| |
| void exposeEvent(QExposeEvent *) |
| { |
| bool useGreenColor = false; |
| QRect rect(0, 0, width(), height()); |
| m_backingStore->resize(QSize(width(), height())); |
| |
| qint32 peekerId = QX11Info::generatePeekerId(); |
| if (peekerId == -1) { |
| qWarning() << "Internal error: QX11Info::generatePeekerId() returned -1"; |
| exit(EXIT_FAILURE); |
| } |
| |
| while (!interrupted()) { // Begin a long operation |
| m_backingStore->beginPaint(rect); |
| QPaintDevice *device = m_backingStore->paintDevice(); |
| QPainter painter(device); |
| painter.fillRect(rect, useGreenColor ? Qt::green : Qt::red); |
| useGreenColor = !useGreenColor; |
| painter.drawText(rect, Qt::AlignCenter, QStringLiteral("Press any key to exit.\n" |
| "(make sure the window is in focus when testing)\n\n If key press does not " |
| "immediately exit the application,\n then that should be considered a bug/regression." |
| "\n\n A demo might appear frozen to some window managers\n and therefore " |
| "might get grayed out (e.g Unity), this is the expected behavior.\n On KWin, for " |
| "example, this demo does not get grayed out.\n Resizing the window on any system will " |
| "cause rendering artefacts, that is not a bug,\n but simply the way the test is " |
| "implemented.")); |
| m_backingStore->endPaint(); |
| m_backingStore->flush(rect); |
| QThread::msleep(500); // Reduce the speed of re-painting (blinking) |
| |
| QX11Info::peekEventQueue([](xcb_generic_event_t *event, void *data) { |
| bool isKeyPress = (event->response_type & ~0x80) == XCB_KEY_PRESS; |
| if (isKeyPress) { |
| IntensivePainter *painter = static_cast<IntensivePainter *>(data); |
| painter->stopPainting(); |
| } |
| return isKeyPress; |
| }, this, QX11Info::PeekOption::PeekFromCachedIndex, peekerId); |
| } |
| |
| QX11Info::removePeekerId(peekerId); |
| exit(EXIT_SUCCESS); |
| } |
| |
| private: |
| QBackingStore *m_backingStore; |
| bool m_stopPainting = false; |
| }; |
| |
| int main(int argc, char** argv) |
| { |
| QGuiApplication app(argc, argv); |
| |
| IntensivePainter painterWindow; |
| painterWindow.show(); |
| |
| return app.exec(); |
| } |