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++ // Copyright (C) 2025 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
++
++ #include <QApplication>
++ #include <QPushButton>
++ #include "widgettest.h"
++
++ int main(int argc, char *argv[])
++ {
++ QApplication app(argc, argv);
++
++ HelloWidget *widget = new HelloWidget;
++ widget->resize(400, 400);
++
++ QWidget *tlw = nullptr;
++
++ QPushButton *btn = new QPushButton("Make it a child widget", widget);
++ QObject::connect(btn, &QPushButton::clicked, widget, [&] {
++ if (!tlw) {
++ btn->setText("Make it a top-level");
++ tlw = new QWidget;
++ tlw->resize(600, 600);
++ widget->setParent(tlw);
++ widget->move(0, 0); // why is this needed?
++ widget->show();
++ tlw->show();
++ widget->update();
++ } else {
++ btn->setText("Make it a child widget");
++ widget->setParent(nullptr);
++ widget->show();
++ delete tlw;
++ tlw = nullptr;
++ }
++ });
++
++ widget->show();
++
++ int r = app.exec();
++
++ if (!widget->parent())
++ delete widget;
++
++ return r;
++ }