GameKit Framework

#import <UIKit/UIKit.h>
#import <GameKit/GameKit.h>

@interface ViewController : UIViewController<GKLeaderboardViewControllerDelegate>

-(IBAction)updateScore:(id)sender;
-(IBAction)showLeaderBoard:(id)sender;

@end


#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    if([GKLocalPlayer localPlayer].authenticated == NO)
    {
      [[GKLocalPlayer localPlayer]
      authenticateWithCompletionHandler:^(NSError *error)
      {
         NSLog(@"Error%@",error);
      }];
    }   
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
- (void) updateScore: (int64_t) score
forLeaderboardID: (NSString*) category
{
    GKScore *scoreObj = [[GKScore alloc]
    initWithCategory:category];
    scoreObj.value = score;
    scoreObj.context = 0;
    [scoreObj reportScoreWithCompletionHandler:^(NSError *error) {
        // Completion code can be added here
        UIAlertView *alert = [[UIAlertView alloc]
        initWithTitle:nil message:@"Score Updated Succesfully"
        delegate:self cancelButtonTitle:@"Ok" otherButtonTitles: nil];
        [alert show];

    }];
}
-(IBAction)updateScore:(id)sender{
    [self updateScore:200 forLeaderboardID:@"tutorialsPoint"];
}
-(IBAction)showLeaderBoard:(id)sender{
    GKLeaderboardViewController *leaderboardViewController =
    [[GKLeaderboardViewController alloc] init];
    leaderboardViewController.leaderboardDelegate = self;
    [self presentModalViewController:
    leaderboardViewController animated:YES];

}
#pragma mark - Gamekit delegates
- (void)leaderboardViewControllerDidFinish:
(GKLeaderboardViewController *)viewController{
    [self dismissModalViewControllerAnimated:YES];
}

@end