Translucent top widget - mouse events

[Talei]

Hello,
I do have translucent widget (setAttribute( Qt::WA_TranslucentBackground, true);) with is top level widget and stays on top. Widget is transparent and everything do works (at least on Win) fine.

But there is one problem, I want to paint on that widget by mouse, so I do overrider mousePress/Move/Release but unfortunately, because widget is transparent, mouse events are not received by that widget.

Question: is there a clean way to force Qt to grab mouse inputs for that widget regardless of it's transparency, so if I do click on that transparent widget I will receive events for that widget (grabMouse don't work, tried that already).

Thanks for any suggestions.

UPDATE: Under that widget is just OS apps/background whatever this widget is covering and not another Qt widget.