REFERENCE GUIDE

Return valueIParamContains the current caret position in its high-order word andthe window handle of the list box in its low-order word.The return value specifies the action which the application performed inresponse to the message. A return value of -2 indicates that theapplication handled all apsects of selecting the item and wants no furtheraction by the list box. A return value of -1 indicates that the list boxshould perform the default action in response to the key stroke. A returnvalue of zero or greater specifies the index of an item in the list box andindicates that the list box should perform the default action for the keystroke on the given item.WM_CHILDACTIVATEThis message is sent to a child window's parent window when theSetWindowPos function moves a child window.Parameters wParam Is not used.IParamIs not used.WM_CLEARThis message deletes the current selection.Parameters wParam Is not used.IParam Is not used.WM_CLOSEThis message occurs when a window is closed.Parameters wParam Is not used.Default actionCommentsIParamIs not used.The DefWindowProc function calls the DestroyWindow function todestroy the window.An application can prompt the user for confirmation, prior to destroying awindow, by processing the WM_CLOSE message and calling theDestroyWindow function only if the user confirms the choice.Chapter 6, Messages directory 643