title: The correct way of adding a UINavigationController to a existing UIViewController
body: <p>I'm trying to add a UINavigationController to my existing view controller by adding this in ViewDidLoad:</p>
  
  <pre><code>- (void)viewDidLoad
  {
      [super viewDidLoad];
  
      navController = [[UINavigationController alloc]init];
  
      [self.view addSubview:navController.view];
  }
  </code></pre>
  
  <p>But by doing it this way, it completely blocks my view. It puts a UINavigationBar on the top but the rest of the view doesn't respond to input.</p>
  
  <p>This is how I am presenting the view. The <strong><em>SecondViewController</em></strong> is the one I want to have a NavController: </p>
  
  <pre><code>UITabBarController *tabController = [[UITabBarController alloc] init];
  
  FirstViewController *viewController1 = [[FirstViewController alloc] initWithNibName:@"CardsViewController" bundle:nil];
  
  UITabBarItem *tab1 = [[UITabBarItem alloc] initWithTitle:@"First" 
                                                     image:[UIImage imageNamed:@"img1.png"] tag:1];
  [viewController1 setTabBarItem:tab1];    
  
  SecondViewController *viewController2 = [[SecondViewController alloc] initWithNibName:@"ShoppingViewController" bundle:nil];
  
  UINavigationController *SecondViewNavCont = [[UINavigationController alloc]initWithRootViewController:viewController2];
  
  UITabBarItem *tab2 = [[UITabBarItem alloc] initWithTitle:@"Second" 
                                                     image:[UIImage imageNamed:@"img2.png"] tag:2];
  [SecondViewNavCont setTabBarItem:tab2];
  
  UIViewController *viewController3 = [[UIViewController alloc] init];
  UITabBarItem *tab3 = [[UITabBarItem alloc] initWithTitle:@"Third" 
                                                     image:[UIImage imageNamed:@"img3.png"] tag:3];
  [viewController3 setTabBarItem:tab3];
  
  
  tabController.viewControllers = [NSArray arrayWithObjects:viewController1, 
                                   viewController2, 
                                   viewController3, 
                                   nil];
  
  [self.view addSubview:tabController.view];
  </code></pre>