Advanced MFC Programming

Chapter 10. Bitmap
Next we create a brush with standard button face color and used it to fill the grayed image (By default,
the standard button face color is light gray. It can also be customized to other colors):
……
……
brush.CreateSolidBrush(::GetSysColor(COLOR_BTNFACE));
pBrOld=dcColor.SelectObject(&brush);
dcColor.PatBlt
(
0, 0,
bm.bmWidth, bm.bmHeight,
PATCOPY
);
dcColor.SelectObject(pBrOld);
brush.DeleteObject();
dcColor.SetBkColor(RGB(255, 255, 255));
dcColor.SetTextColor(RGB(0, 0, 0));
The button face color is retrieved by calling ::GetSystColor(…) API function. Actually, all the
standard colors defined in the system can be retrieved by calling this function. Next, we draw the
highlighted outline of the grayed bitmap using the standard highlighted color:
……
……
brush.CreateSolidBrush(::GetSysColor(COLOR_BTNHIGHLIGHT));
pBrOld=dcColor.SelectObject(&brush);
pBmpHilightOld=dcMono.SelectObject(&bmpHilight);
dcColor.BitBlt
(
0, 0,
bm.bmWidth, bm.bmHeight,
&dcMono,
0, 0,
0x00B8074A
);
dcColor.SelectObject(pBrOld);
brush.DeleteObject();
dcMono.SelectObject(pBmpHilightOld);
Also, the shadowed outline is drawn on the grayed image in the same way:
……
brush.CreateSolidBrush(::GetSysColor(COLOR_BTNSHADOW));
pBrOld=dcColor.SelectObject(&brush);
pBmpShadowOld=dcMono.SelectObject(&bmpShadow);
dcColor.BitBlt
(
0, 0,
bm.bmWidth, bm.bmHeight,
&dcMono,
0, 0,
0x00B8074A
);
dcColor.SelectObject(pBrOld);
brush.DeleteObject();
dcMono.SelectObject(pBmpShadowOld);
dcColor.SelectObject(pBmpOld);
}
return (HBITMAP)bmpGray.Detach();
Finally, some clean up routines. Before this function exits, we call function CBitmap::Detach() to
detach HBITMAP type handle from CBitmap type variable. This is because we want to leave the HBITMAP
handle for further use. If we do not detach it, when CBitmap type variable goes out of scope, the destructor
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