title: Twitter widget callback
body: <p>How do I call a callback when a <a href="https://twitter.com/about/resources/widgets/widget_search">Twitter widget</a> is rendered?</p>
  
  <p>Using the code they provided:</p>
  
  <pre><code>TWTR.Widget({data: something}).render().setUser('me').start();
  </code></pre>
  
  <p>Twitter has notoriously spotty service and frequent long load times. How do I add a callback on loading of the TWTR widget, so I can show my users a loader in the meantime?</p>