Question

I am building a game in Cocos2d-iPhone, and while I was updating to iOS 6, I noticed that Apple changed the way Game Center authentication is done, using authenticateHandler instead of authenticateWithCompletionHandler.

I added the new authentication method, but the game now crashes if a player is not already logged in to Game Center. There is no problem authenticating if a user is already logged in.

Here is my code:

if(SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"6.0"))
{
    GKLocalPlayer *localPlayer = [GKLocalPlayer localPlayer];
    localPlayer.authenticateHandler = ^(UIViewController *viewController, NSError *error)
    {
        if (viewController != nil)
        {
            AppController *appDelegate = (AppController*)[UIApplication sharedApplication].delegate;

            [delegate.viewController presentViewController:viewController animated:YES completion:nil];
        }
        else if (localPlayer.isAuthenticated)
        {
            NSLog(@"Player authenticated");
        }
        else
        {
            NSLog(@"Player authentication failed");
        }
    };
}

It seems like it’s crashing when trying to present the Game Center viewController, even though I use the exact same code to present the GKTurnBasedMatchmakerViewController with no issues.

Any help would be much appreciated.

EDIT:
Here is the exception getting thrown on crash:

Uncaught Exception UIApplicationInvalidInterfaceOrientation: Supported orientations has no common orientation with the application, and shouldAutorotate is returning YES

Answer 1

Here you can find useful information about your crash, I think it is the underlying reason.
https://developer.apple.com/library/ios/#releasenotes/General/RN-iOSSDK-6_0/_index.html

Apps should provide the delegate method application:supportedIntefaceOrientationsForWindow and ensure that portrait is one of the returned mask values.

I added below code to fix this crash.

- (NSUInteger)application:(UIApplication*)application supportedInterfaceOrientationsForWindow:(UIWindow*)window
{
    return UIInterfaceOrientationMaskAllButUpsideDown;
}