qtbase/examples/widgets/desktop/systray/main.cpp

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#include <QApplication>

#ifndef QT_NO_SYSTEMTRAYICON

#include <QMessageBox>
#include "window.h"

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);

    if (!QSystemTrayIcon::isSystemTrayAvailable()) {
        QMessageBox::critical(nullptr, QObject::tr("Systray"),
                              QObject::tr("I couldn't detect any system tray "
                                          "on this system."));
        return 1;
    }
    QApplication::setQuitOnLastWindowClosed(false);

    Window window;
    window.show();
    return app.exec();
}

#else

#include <QLabel>
#include <QDebug>

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    QString text("QSystemTrayIcon is not supported on this platform");

    QLabel *label = new QLabel(text);
    label->setWordWrap(true);

    label->show();
    qDebug() << text;

    app.exec();
}

#endif