Game Center Leaderboards with cocos2d Cause Unresponsive App - iphone

Question

OK, so I'm trying to show Apple Game Center Leaderboards called from within my cocos2d game.
I've had some trouble doing so.
I did eventually stumble upon this and I implemented the following in one of my CCScene classes (I slightly modified the original code to prevent a compiler warning).
- (void)showLeaderboardForCategory:(NSString *)category
{
// Create leaderboard view with default Game Center style
leaderboardController = [[GKLeaderboardViewController alloc] init];
// If view controller was successfully created...
if (leaderboardController != nil)
{
// Leaderboard config
leaderboardController.leaderboardDelegate = self; // leaderboardController will send messages to this object
leaderboardController.category = category;
leaderboardController.timeScope = GKLeaderboardTimeScopeAllTime;
// Create an additional UIViewController to attach the GKLeaderboardViewController to
vc = [[UIViewController alloc] init];
// Add the temporary UIViewController to the main view
[[CCDirector sharedDirector].view.window addSubview:vc.view];
// Tell UIViewController to present the leaderboard
[vc presentModalViewController:leaderboardController animated:YES];
}
}
- (void)leaderboardViewControllerDidFinish:(GKLeaderboardViewController *)viewController
{
[vc dismissViewControllerAnimated:YES completion:nil];
}
And, it works! At least when I call it, it does display the Leaderboard properly.
The only problem is, when I tap "Done" on the Leaderboard and the modal view dismisses, my CCScene no longer responds to tap events.
What do I need to do to regain responsiveness?

Answer 1

Refer sample plain cocos2d project:
-(void)showLeaderboard
{
GKLeaderboardViewController *leaderboardViewController = [[GKLeaderboardViewController alloc] init];
leaderboardViewController.leaderboardDelegate = self;
AppController *app = (AppController*) [[UIApplication sharedApplication] delegate];
[[app navController] presentModalViewController:leaderboardViewController animated:YES];
[leaderboardViewController release];
}
Delegate Function:
-(void) leaderboardViewControllerDidFinish:(GKLeaderboardViewController *)viewController
{
AppController *app = (AppController*) [[UIApplication sharedApplication] delegate];
[[app navController] dismissModalViewControllerAnimated:YES];
}