title: How to refresh a panel after data is loaded?
body: <p>I have a extjs panel rendered inside a div like this:</p>
  
  <pre><code>panel = new Ext.Panel({
              layout : 'fit',
              renderTo: 'my_div',
              monitorResize: true, // relay on browser resize
              height: 500,
              autoWidth: true,
              items : [
                  centerPanel
              ],
              plain : true
          });
  </code></pre>
  
  <p>After the page has loaded the panel is empty, but when I resize the browser the contents appears by magic!</p>
  
  <p>I think the data has not finished loading when the panel is rendered the first time.</p>
  
  <p>How can I get the contents to show without resizing the browser?</p>