title: How to wait a ExtJS Panel to render before expand?
body: <p>I have an <code>infoContainer</code> extending an <code>Ext.panel.Panel</code> in ExtJS 4.0.7 with these properties (only relevant shown):</p>
  
  <ul>
  <li>collapsible: true</li>
  <li>collapsed: true</li>
  <li>disabled: true</li>
  <li>forceLayout: true</li>
  </ul>
  
  <p>I've some modifications (some render) to apply on components (like textfields, checkboxes, etc), so I do this in the <code>beforeexpand</code> of the panel.  But, when the panel expands, we clearly see modifications on components after the panel is visible.  So, I need this logic to be complete <strong>before</strong> we see the panel open.</p>
  
  <p>So, can I restrict the expand of the panel to happen only when the logic of <code>beforeexpand</code> is done? and how to do this?</p>