Short answer: You shouldn't.
You class spielplan
(which should be renamed to PMGameBoard
) is probably a controller class that manages views, including the tableView. So it's the responsibility of this controller to reload the tableView's data should need be.
The external event from your app delegate, whatever it is, should be made available to the spielplan
instance by some means of notification. The exact method of communication depends on the type of event (NSNotification
, ...). See this objc.io article.