CMDIChildWndEx::GetTaskbarThumbnailClipRect
Called by the framework when it needs to select a portion of a window's client area to display as that window's thumbnail in the taskbar.
virtual CRect GetTaskbarThumbnailClipRect() const;
Return Value
A rectangle in windows coordinates. This rectangle is mapped to the client area of the top level frame. The rectangle should be empty to clear the clipping rectangle.
Requirements
Header: afxmdichildwndex.h