title: jQuery Mobile, transparent black overlay effect
body: <p>I am currently using jQuery Mobile for a Phonegap application and I was wondering how could I add a black overlay that is semi transparent over only the content of a page. I don't want it to cover the top and bottom navbars. This would happen while I place an AJAX call to the server.</p>
  
  <p>This effect is similar to the Twitter iOS app, when you are typing in the search bar.</p>
  
  <pre><code>$('#search').ajaxStart(function() {
    // what do I put here?
  });
  </code></pre>
  
  <p>Thank you for your help everyone! Much appreciated.</p>