title: How can I fix my navigation bar back button?
body: <p>Hi I've been trying to change my <em>back button</em> in my application's navigation bar. The problem is that I see the change when I load the view twice.</p>
  
  <p>I've searched for the answer several times but I don't see what I really want. In fact, I'm new at this language so it's difficult.</p>
  
  <p>What I tried is putting the following lines in the <code>viewWillAppear</code> method and others*:</p>
  
  <pre class="lang-swift prettyprint-override"><code>nav?.navigationBar.backItem?.title = "Messages"
  </code></pre>
  
  <p>The result is that when I enter the view I see the <em>back button's title</em> as <em>Back</em>. Then if I press on that button and enter the view again the title changes as I want. On the other hand, what I want is to change the title when I load the view first.</p>
  
  <p>*-> I've tried the same line in <code>viewDidLoad</code> too see if that does anything and in <code>viewWillDisappear</code> of the previous view, but nothing happens.</p>