Setting main Window on top using flags parameter not working as I expected

[David A.]

Environment: Windows7 / Qt 5.4.2 with QtCreator 3.4.1 / MSVC2013

I'm having problem setting a qml window on top. I create a new QtQuick 2.4 project and set the flags property as follows:

import QtQuick 2.4
import QtQuick.Window 2.2

Window {
    visible: true
    flags: Qt.Window | Qt.WindowStaysOnTopHint
    MainForm {
        anchors.fill: parent
        mouseArea.onClicked: {
            Qt.quit();
        }
    }
}

The result is a window without title bar that stays on top.

I have managed to do what I needed using C++ code, but it'd be great if I can learn why the previous QML code doesn't work...

Just for completeness, you can do this in C++ (using Qt 5.4) as follows:

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

    QQmlApplicationEngine engine;
    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));

    QObject *topLevel = engine.rootObjects().value(0);
    QQuickWindow *window = qobject_cast<QQuickWindow *>(topLevel);
    Qt::WindowFlags flags = window->flags();
    window->setFlags(flags | Qt::WindowStaysOnTopHint);

    return app.exec();
}

References:

• Window QML Type
• Windows Flags example
• YARP qt viewer main.cpp

[p3c0]

@David-A. It works on Ubuntu with Qt 5.4.1. Result is a Window with title bar and stays on top as expected. Could be a bug on windows. Try searching on https://bugreports.qt.io