GKTurnBasedEventListener could not be set to delegate of my ViewController?
问题 In objC the syntax written by Rawendrich for GKTurnBasedEventListener , which was GKTurnBasedEventHandler there at that time, now changed by Apple is as below. if (!gameCenterAvailable) return; void (^setGKEventHandlerDelegate)(NSError *) = ^ (NSError *error) { GKTurnBasedEventHandler *ev = [GKTurnBasedEventHandler sharedTurnBasedEventHandler]; ev.delegate = self; }; NSLog(@"Authenticating local user..."); if ([GKLocalPlayer localPlayer].authenticated == NO) { [[GKLocalPlayer localPlayer]