[Qt-interest] How to get window handle from QWidget

[Matthias Pospiech]

I have a camera library for windows which uses in its examples MFC. They 
have a function to automatically display
the camera image to a window by passing the pointer of the camera image 
memory and the window handle to a function

is_RenderBitmap( m_hCam, m_lMemoryId, m_hWndDisplay, m_nRenderMode );

the handle is retrieved in MFC using
m_hWndDisplay = GetDlgItem( IDC_DISPLAY )->m_hWnd; // set display window 
handle

Now I want to use this library in Qt. I now would like to know how to 
get the window handle (which I assume ever window
in a windows application has) so that I can work with the RenderBitmap 
function.
If this should not work/or work completely different I would as well 
like to know that.

Matthias