We can use the Invalidate in the WM_PAINT. - call Invalidate flag after invalidate no - - - - WM_PAINT check_invalidate=1; WM_PAINT 1 - WM_KEYUP check_invalidate=1; WM_PAINT 2 - 3 WM_KEYUP check_invalidate=1; WM_PAINT 4 -> WM_PAINT check_i…