code: func (v *MenuItem) SetDetailedAction(act string) {
  	cstr1 := (*C.gchar)(C.CString(act))
  	defer C.free(unsafe.Pointer(cstr1))
  
  	C.g_menu_item_set_detailed_action(v.native(), cstr1)
  }
docs: //SetDetailedAction is a wrapper around g_menu_item_set_detailed_action().