title: iOS UITextField changes position when text is changed
body: <p>I use this to center a text field over something relevant:</p>
  
  <pre><code>[textField setCenter:[someObject center]];
  [textField becomeFirstResponder];
  </code></pre>
  
  <p>This looks great, nice and centered over the object, ready to accept text. I'd like the text formated a certain way, so in the editing changed handler, I revise the text and set to the new text:</p>
  
  <pre><code>[textField setText:newText];
  </code></pre>
  
  <p>When I do this, the text field will jump to its the old position, from before it was centered. I'd like the text field to stay centered over the object.</p>
  
  <p>My experience is that there is likely a better way to do this, i.e. move the text field and dynamically change its contents, without have to work around various quirks. Any advice?</p>