Zitat:
WM_DRAWITEM
idCtl = (UINT) wParam; // control identifier
lpdis = (LPDRAWITEMSTRUCT) lParam; // item-drawing information
The WM_DRAWITEM message is sent to the owner window of an owner-drawn button, combo box, list box, or menu when a visual aspect of the button, combo box, list box, or menu has changed.
Parameters
idCtl
Value of wParam. Specifies the identifier of the control that sent the WM_DRAWITEM message. If the message was sent by a menu, this parameter is zero.
lpdis
Value of lParam. Points to a DRAWITEMSTRUCT structure containing information about the item to be drawn and the type of drawing required.
Return Value
If an application processes this message, it should return TRUE.
Das meinte er mit der 0