[Qt-interest] Transparent QWidget

[matteo]

Hi,
I need create a transparent QWidget. I try with Api Windows

SetWindowLong(oHandle, GWL_EXSTYLE, GetWindowLong(oHandle, GWL_EXSTYLE) 
WS_EX_LAYERED);
SetLayeredWindowAttributes(oHandle, 0, (255 * 70) / 100, LWA_ALPHA);

but I would prefer to use portable instructions.
Is it possible?

Thanks
Teo