The WM_ICONERASEBKGND message is sent to a minimized window when the background of the icon must be filled before painting the icon. A window receives this message only if a class icon is defined for the window; otherwise, WM_ERASEBKGND is sent.
WM_ICONERASEBKGND
hdc = (HDC) wParam; // handle of device context
Parameters
hdc
Value of wParam. Identifies the device context of the icon.
Return Values
An application should return nonzero if it processes this message.
Remarks
The DefWindowProc function fills the icon background with the class background brush of the parent window.
See Also