在视图控制器上添加导航栏

我是 iOS 新手，我想在我的视图控制器上添加一个导航栏，左侧有 2 个按钮，右侧有订阅按钮。我不知道如何做到这一点..到目前为止，我刚刚从界面生成器添加了一个导航栏，在 .h 文件中为其创建了一个（强）引用，并进行了以下编码。

 navBar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 20, 1026, 50)];
[navBar setTintColor:[UIColor clearColor]];
[navBar setBackgroundColor:[UIColor redColor]];
[navBar setDelegate:self];
[self.view addSubview:navBar];
UIBarButtonItem *bi1 = [[UIBarButtonItem alloc] initWithTitle:@"subscribe" style:UIBarButtonItemStyleBordered target:self action:@selector(editBotton)];

bi1.style = UIBarButtonItemStyleBordered;

bi1.tintColor =[UIColor colorWithWhite:0.305f alpha:0.0f];

self.navigationItem.rightBarButtonItem = bi1;

但什么也没发生..请帮忙

您可以在AppDelegate中添加，

 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
    {
        UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:@"MainStoryboard_iPhone"
                                                                 bundle: nil];
     
        SampleViewController *mainViewController = (SampleViewController*)[mainStoryboard
                                                           instantiateViewControllerWithIdentifier: @"SampleViewController"];
     
        UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:mainViewController];
     
        self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
        [self.window setRootViewController:navigationController];
        [self.window setBackgroundColor:[UIColor whiteColor]];
        [self.window makeKeyAndVisible];
     
        return YES;
    }