test create Game center

Game center .m

1) #import <GameKit/GameKit.h>
2)
    bool gameCenterEnabled;
    NSString *leaderboardIdentifier;

@property(nonatomic)bool gameCenterEnabled;
@property(strong,nonatomic)NSString *leaderboardIdentifier;
-(void)authenticateLocalPlayer;

3)@synthesize gameCenterEnabled , leaderboardIdentifier;

4)
-(void)authenticateLocalPlayer{
    GKLocalPlayer *localPlayer = [GKLocalPlayer localPlayer];

    localPlayer.authenticateHandler = ^(UIViewController *viewController, NSError *error){
        if (viewController != nil) {
            [self presentViewController:viewController animated:YES completion:nil];
        }
        else{
            if ([GKLocalPlayer localPlayer].authenticated) {
                gameCenterEnabled = YES;

                // Get the default leaderboard identifier.
                [[GKLocalPlayer localPlayer] loadDefaultLeaderboardIdentifierWithCompletionHandler:^(NSString *leaderboardIdentifier, NSError *error) {

                    if (error != nil) {
                        NSLog(@"%@", [error localizedDescription]);
                    }
                    else{
                        leaderboardIdentifier = leaderboardIdentifier;
                        NSLog(@"%@",leaderboardIdentifier);
                    }
                }];
            }

            else{
                gameCenterEnabled = NO;
            }
        }
    };

}

5) [self authenticateLocalPlayer];   // viewdidload