title: How do I set a custom view back button
body: <p>In View Controller A, in viewDid Load I have this:</p>
  
  <pre><code>UIImage * backButtonImage = [UIImage imageNamed: @"bar-arrow"];
  UIBarButtonItem* b = [[UIBarButtonItem alloc] initWithImage:backButtonImage style:UIBarButtonItemStylePlain target:nil action:nil];
  self.navigationItem.backBarButtonItem = b;
  </code></pre>
  
  <p>Still In the next view controller's nav. bar I get this:</p>
  
  <p><img src="https://i.stack.imgur.com/zuwyS.png" alt="enter image description here"></p>
  
  <p>In other words - the original back arrow of IOS7 still shows. cannot get rid of it!!</p>