title: How can I init a text field in a UIAlertView
body: <p>The updated <code>UIAlertView</code> now has a style which allows a Text input field in <code>UIAlertView</code> i.e.</p>
  
  <pre><code>alert.alertViewStyle = UIAlertViewStylePlainTextInput;
  </code></pre>
  
  <p>This works well but I wanted to init the input text with a defualt text like "sample".</p>
  
  <p>I see that folks in the past have used undocumented api like (which works great)</p>
  
  <pre><code>[alert addTextFieldWithValue:@"sample text" label:@"Text Field"];
  </code></pre>
  
  <p>but since this is still not an official Apple public API I can't use it.</p>
  
  <p>Any other way to handle this? I did try to init in <code>willPresentAlertView</code> but text field seem to be read-only.</p>
  
  <p>Thanks</p>