title: Problem over-riding the Back button in iOS
body: <p>I have a UITableViewController A that is pushing UITableViewController B onto the stack.</p>
  
  <p>In A i have the code:</p>
  
  <pre><code>self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Trending" 
                                                                                       style:UIBarButtonItemStylePlain 
                                                                                      target:self 
                                                                                      action:@selector(backButtonClicked:)];
  </code></pre>
  
  <p>backButtonClicked: is also implemented.</p>
  
  <p>B has the title Trending, but when I click it, it doesn't ever reach backButtonClicked:</p>
  
  <p>Why is this?</p>