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// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
#include <QtGui>
// This example demonstrates how to create QGuiApplication
// without calling exec(), and then exiting main() without
// shutting down the Qt event loop.
class ClickWindow: public QRasterWindow
{
public:
ClickWindow() {
qDebug() << "ClickWindow constructor";
}
~ClickWindow() {
qDebug() << "ClickWindow destructor";
}
void paintEvent(QPaintEvent *ev) override {
QPainter p(this);
p.fillRect(ev->rect(), QColorConstants::Svg::deepskyblue);
p.drawText(50, 100, "Application has started. See the developer tools console for debug output");
}
void mousePressEvent(QMouseEvent *) override {
qDebug() << "mousePressEvent(): calling QGuiApplication::quit()";
QGuiApplication::quit();
}
};
int main(int argc, char **argv)
{
qDebug() << "main(): Creating QGuiApplication object";
QGuiApplication *app = new QGuiApplication(argc, argv);
QObject::connect(app, &QCoreApplication::aboutToQuit, [](){
qDebug() << "QCoreApplication::aboutToQuit";
});
qDebug() << "main(): Creating ClickWindow object";
ClickWindow *window = new ClickWindow();
window->show();
// We can exit main; the Qt event loop and the emscripten runtime
// will keep running, as long as Emscriptens EXIT_RUNTIME option
// has not been enabled.
qDebug() << "main(): exit";
}
// Global variables are created before main() as usual, but not destroyed
class Global
{
public:
Global() {
qDebug() << "Global constructor";
}
~Global() {
qDebug() << "Global destructor"; // <- will not be printed
}
};
Global global;
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