title: SortableAsyncListView sort
body: <pre><code>    &lt;s:DataGrid id="materialsList"&gt;
          &lt;s:dataProvider&gt;
              &lt;c:SortableAsyncListView list="{materials}" /&gt;
          &lt;/s:dataProvider&gt;
          ....
  </code></pre>
  
  <p>materials is PagedQuery.
  When I'm sorting by GridColumn with complex dataField ("group.name") I'll getting sort[0]=null and procedure on server-side can't order materials by this field. How to sort SortableAsyncListView by complex field?</p>