title: Adding ExtJS4 components to ExtJS3 components?
body: <p>I've got an ExtJS3 application which could benefit from the <a href="http://www.sencha.com/blog/ext-js-4-preview-drawing-and-charting/" rel="nofollow">ExtJS4 SVG stuffs</a>. Online there is an <a href="http://dev.sencha.com/deploy/ext-4.0.1/examples/sandbox/sandbox.html" rel="nofollow">example</a> of how to use sandbox mode to include ExtJS4 components in an ExtJS3 application... but in the example the ExtJS4 components are in their own floating <a href="http://docs.sencha.com/ext-js/4-0/#/api/Ext.window.Window" rel="nofollow">window</a>, so the ExtJS4 components aren't really added to ExtJS3 components; they just co-exist rather independently.</p>
  
  <p>Is there a way to add an ExtJS4 component to an ExtJS3 component while running in sandbox mode? For example:</p>
  
  <pre><code>var item = Ext4.create("Ext.panel.Panel", { // ExtJS4
      /* config */
  });
  var parent = new Ext.Panel({ // ExtJS3
      items:[item],
      /* more config */
  });
  </code></pre>
  
  <p>If I try something like this, I usually get an error like...</p>
  
  <pre><code>this.container is null (http://localhost:4000/path/ext-4.0.0/builds/ext-all-sandbox-debug.js:27723)
  </code></pre>