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++ // Copyright (C) 2023 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++
++ #include "widget.h"
++
++ #include <QApplication>
++ #include <QAudioDevice>
++ #include <QMediaDevices>
++ #include <QMessageBox>
++
++ int main(int argc, char *argv[])
++ {
++ QApplication a(argc, argv);
++ const QAudioDevice inputDevice = QMediaDevices::defaultAudioInput();
++ if (inputDevice.isNull()) {
++ QMessageBox::warning(nullptr, "audio",
++ "There is no audio input device available.");
++ return -1;
++ }
++
++ Widget w(inputDevice);
++ w.resize(800, 600);
++ w.show();
++
++ return a.exec();
++ }