Nested Objects for a Data Provider in a Data Grid, not displaying data

Question

Hi, I have a datagrid and the dataprovider for this grid is the result of a RPC call. The result set has the following structure:
Array
[0]->Object #1
      [one] => 1
      [two] => 1
      [three] => Object #2
          [apple1] = > Object #3
              [color] =>    red
              [rate] => 20
          [apple2] => Object #4 ( the    number of apples is dynamic, apple3,apple4 .. and so on)
              [color] =>    blue
              [rate] => 100
and so on ... so the number of apple objects will vary since its
dynamic. How do I display this data in a datagrid ??? Please help!! I
saw many articles on creating the "Nested DataGridColumn " classes...
like this :
http://active.tutsplus.com/tutorials/flex/working-with-the-flex-datagrid-and-nested-data-structures/
it helps, but the problem with my data is that some of the indexes (like  apple1,apple2 etc) are dynamic.
Also, my flex application is a desktop application (in case that matters). Just to see whats going on, I
dropped all the nested arrays and used a plain simple one-dimensional array. Even in this case the data
isnt getting displayed.
I dont know what im doin wrong. the datafields, labels etc e'thing is correct. I even debugged and
im getting the result on the flex side. whats going on ?

Answer 1

No luck ... i converted the result set to a List, and even tried with an iList. Same problem -  nothing gets displayed...
I have no idea whats happening ....
This is my code :
[Bindable]private var privilegesArray:ArrayCollection = new ArrayCollection();
public function init():void{ // called on creation complete
                RO.getPrivileges.addEventListener(ResultEvent.RESULT,handleGetPrivileges);
                RO.getPrivileges();
protected function handleGetPrivileges(event:ResultEvent):void{
                privilegesArray = event.result as ArrayCollection;
<mx:DataGrid id="privilegesDG" dataProvider="{privilegesArray}" width="100%">
        <mx:columns>
            <mx:DataGridColumn headerText="Name" dataField="name" />
            <mx:DataGridColumn headerText="Alias" dataField="alias" />
        </mx:columns>
    </mx:DataGrid>
The data that gets returned is smthing like this : (for the moment I have removed all the nested objects and arrays and returning just a simple plain array)
Array => [0] => Object #1
                          [name] => some name
                          [alias] => alias