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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
#include <QApplication>
#include <QGraphicsView>
#include <QGraphicsScene>
#include <QGraphicsItem>
#include <QMessageBox>
class MyObject : public QObject
{
public:
MyObject(QGraphicsItem *i, QObject *parent = nullptr) : QObject(parent), itemToToggle(i)
{
startTimer(500);
}
protected:
void timerEvent(QTimerEvent *)
{
itemToToggle->setVisible(!itemToToggle->isVisible());
}
private:
QGraphicsItem *itemToToggle;
};
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
QGraphicsView gv;
QGraphicsScene *scene = new QGraphicsScene(&gv);
gv.setScene(scene);
QGraphicsItem *rect = scene->addRect(0, 0, 200, 200, QPen(Qt::NoPen), QBrush(Qt::yellow));
rect->setFlag(QGraphicsItem::ItemHasNoContents);
rect->setFlag(QGraphicsItem::ItemClipsChildrenToShape);
QGraphicsItem *childRect = scene->addRect(0, 0, 100, 100, QPen(Qt::NoPen), QBrush(Qt::red));
childRect->setParentItem(rect);
gv.show();
MyObject o(rect);
QMessageBox::information(0, "What you should see",
"The red rectangle should toggle visibility, so you should see it flash on and off");
return a.exec();
}
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