Solved... A Qwidget representing the screen fails between calls...

[tonnot]

I want to have a 'parent' reference .
I have a private QWidget * w_parent_destiny;

w_parent_destiny = QDesktopWidget().screen();

w_parent_destiny = QDesktopWidget().screen();

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This works only into the function it is created.
Any idea ? Thanks
Answering mysefl .....
.qApp->desktop()->screen();