EVENT_SYSTEM_MENUPOPUPSTART Notes

[This is preliminary documentation and subject to change.]

For this event, the WinEventProc callback function's hwnd, idObject, and idChild parameters refer to the new pop-up menu being displayed, not the parent item. You can retrieve the parent or pop-up menu by calling the IAccessible::get_accParent method.

When an application displays a pop-up menu, the client will receive an EVENT_SYSTEM_MENUSTART event followed almost immediately by this event.