Fully transparent, dragable window

[Redar]

Hello,

I want to create an invisible, frameless, dragable window with two visible buttons.
Frameless an invisible works fine when I use:

setWindowFlags(Qt::FramelessWindowHint);
setAttribute(Qt::WA_TranslucentBackground);

setWindowFlags(Qt::FramelessWindowHint);
setAttribute(Qt::WA_TranslucentBackground);

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Added Buttons are visible.

But if I click around the buttons, where the invisible mainWindow should be, the click goes right through to whatever application there behind is.
I reimplemented the mouseMoveEvent and mousePressEvent, to drag the main window. When the window is visible this works great:

void MainWindow::mouseMoveEvent(QMouseEvent *event)
{
    move(event->globalX()-m_nMouseClick_X_Coordinate,event->globalY()-m_nMouseClick_Y_Coordinate);
}
 
void MainWindow::mousePressEvent(QMouseEvent *event)
{
    m_nMouseClick_X_Coordinate = event->x();
    m_nMouseClick_Y_Coordinate = event->y();
    qDebug() << "mouse press event" << endl;
}

void MainWindow::mouseMoveEvent(QMouseEvent *event)
{
    move(event->globalX()-m_nMouseClick_X_Coordinate,event->globalY()-m_nMouseClick_Y_Coordinate);
}

void MainWindow::mousePressEvent(QMouseEvent *event)
{
    m_nMouseClick_X_Coordinate = event->x();
    m_nMouseClick_Y_Coordinate = event->y();
    qDebug() << "mouse press event" << endl;
}

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If it is invisible nothing happens.

How can I make the invisible area of the mainwindow clickable, so i can drag it?

Regards

Redar

Edit: This program should run on windows