Checks that the UI is in user mode, then activates the control.
LRESULT OnMouseActivate(
   UINT /* nMsg */,
   WPARAM /* wParam */,
   LPARAM /* lParam */,
   BOOL& bHandled 
);
Parameters
- nMsg 
 Reserved.
- wParam 
 Reserved.
- lParam 
 Reserved.
- bHandled 
 Flag that indicates whether the window message was successfully handled. The default is FALSE.
Return Value
Always returns 1.
Requirements
Header: atlctl.h