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++ // Copyright (C) 2016 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++
++ #include "mainwindow.h"
++ #include "window.h"
++ #include <QApplication>
++ #include <QKeySequence>
++ #include <QMenuBar>
++ #include <QMenu>
++ #include <QMessageBox>
++
++ MainWindow::MainWindow()
++ {
++ #ifndef Q_OS_WASM
++ QMenu *menuWindow = menuBar()->addMenu(tr("&Window"));
++ menuWindow->addAction(tr("Add new"), QKeySequence(Qt::CTRL | Qt::Key_N),
++ this, &MainWindow::onAddNew);
++ menuWindow->addAction(tr("Quit"), QKeySequence(Qt::CTRL | Qt::Key_Q),
++ qApp, QApplication::closeAllWindows);
++ #endif
++ onAddNew();
++ }
++
++ void MainWindow::onAddNew()
++ {
++ if (!centralWidget())
++ setCentralWidget(new Window);
++ else
++ QMessageBox::information(this, tr("Cannot Add New Window"),
++ tr("Already occupied. Undock first."));
++ }