title: What to do about "Finishing up a navigation transition in an unexpected state. Navigation Bar subview tree might get corrupted."
body: <p>I'm writing an iPhone app using Appcelerator Titanium Mobile.  I am hiding and showing the tab group based on what window has focus. </p>
  
  <pre><code>dashWin.addEventListener("focus",function(e) {
      if (dashWin.tabGroupVisible == true) {
          dashWin.tabGroupVisible=false;
          tabGroup.animate({bottom:-50,duration:500});
      }
  });
  </code></pre>
  
  <p>The code above hides the tab group when dashWin receives a focus event.  However, I see this message in the Titanium console when the event fires while running in the iPhone simulator:</p>
  
  <blockquote>
    <p>Finishing up a navigation transition in an unexpected state. Navigation Bar subview tree might get corrupted.</p>
  </blockquote>
  
  <p>A Google search turns up one result: <a href="https://stackoverflow.com/questions/5301014/ios-popviewcontroller-unexpected-behavior">Another StackOverflow question</a> that may have a hint as to what's going on.</p>