Making an owner-draw button transparent against its arbitrary background in WINCE
- by EndsOfInvention
Hi
I am trying to place an owner-draw button transparently onto a background. I have no trouble doing this when the background is a solid colour but if the background is an image I cannot seem to get the correct HDC (handle to device context) to Bitblt() the area that button covers.
The HDC that is passed as part of the DRAWITEMSTRUCT gives me a button-default-grey area. If I attempt to get the parent of the HWND and then the device context of that i.e
pdc = GetDC(GetParent(hWnd));
then the background that gets BitBlt'd is the background of the last painted window.
I hope this question makes sense.
this is the code I have:
pdis = (LPDRAWITEMSTRUCT)(lParam);
hdc = pdis->hDC;
button = pdis->CtlID - IDC_BUTOFFSET;
//pdc = GetDC((hWnd));
pdc = GetDC(GetParent(hWnd));
hbm = CreateCompatibleBitmap(pdc, Buttons_[button]->bc.Size.cx, Buttons_[button]->bc.Size.cy);
SelectObject(hdc, hbm);
BitBlt(hdc, 0, 0, Buttons_[button]->bc.Size.cx, Buttons_[button]->bc.Size.cy,
pdc, Buttons_[button]->bc.Position.x, Buttons_[button]->bc.Position.y, SRCCOPY);
TIA
Best regards
Ends
