如何访问ArrayCollection数据

我知道这个可能很简单,但我想不通。

<s:List id="compList"
width="250"
height="350"
creationComplete="compList_creationCompleteHandler(event)"
itemRenderer="itemRenderer.compListItemRenderer"
change="compList_changeHandler(event)"  //when a user select a row, the datagrid will display the data.
>
<s:AsyncListView list="{compinfoResult.lastResult}"/>

</s:List>




<mx:DataGrid id="dataGrid" dataProvider="{compDetailinfoResult.lastResult}">      //The dataGrid display the data fine
<mx:columns>
<mx:DataGridColumn dataField="user" headerText="User"/>
<mx:DataGridColumn dataField="brand" headerText="Brand"/>
<mx:DataGridColumn dataField="compModel" headerText="Model"/>
<mx:DataGridColumn dataField="picture" headerText="Product Picture"/>
</mx:columns>
</mx:DataGrid>


<mx:Image source="??????" />   // I want to display productPicture here too but not sure what to add here.....