AppDelegate.m
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds]; UINavigationController *nav =[[UINavigationController alloc]initWithRootViewController:[[ViewController alloc]init]]; self.window.rootViewController =nav; [self.window makeKeyAndVisible]; return YES; }