specifies the types of toplevel widgets to include. Allowed types are #GTK_UI_MANAGER_MENUBAR, #GTK_UI_MANAGER_TOOLBAR and #GTK_UI_MANAGER_POPUP.
a newly-allocated #GSList of all toplevel widgets of the requested types. Free the returned list with g_slist_free().
2.4
Obtains a list of all toplevel widgets of the requested types.