title: How to change the text of a BarButtonItem on the NavigationBar?
body: <p>I am trying to create a list of items that can be edited.  Something like this:</p>
  
  <p><img src="https://i.stack.imgur.com/BirSR.png" alt="enter image description here"></p>
  
  <p>To that end, I added a NavigationBar to the top of the view, then added 2 Bar Button Items in XCode designer.  I set the identifier for the button on the left to Add, for the button on the right to Edit.</p>
  
  <p>When I click the Edit, I want to change the text to Done.  I've tried various ways, e.g. <code>btnEdit.Title = "Done"</code>, but it simply doesn't take.  </p>
  
  <p>I've seen several blog posts recommending .SetTitle, but UIButtonBarItem doesn't have that method (at least in MonoTouch).</p>
  
  <p>So, how can I change the title of the Edit button? </p>