title: [self.navigationController pushViewController:ngView animated:YES]; not working
body: <p>If i use </p>
  
  <pre><code> NGViewController *ngView = [[NGViewController alloc]initWithNibName:Nil bundle:Nil];
  [self presentViewController:ngView animated:NO completion:nil];
  </code></pre>
  
  <p>above code the controller will go to NGViewController page.</p>
  
  <p>But if I use this navigation controller </p>
  
  <pre><code>NGViewController *ngView = [[NGViewController alloc]initWithNibName:Nil bundle:Nil];
  [self.navigationController pushViewController:ngView animated:YES];
  </code></pre>
  
  <p>the Controller will be in same page.</p>
  
  <p>Can any one tell that what's the problem.</p>