[flexcoders] AdvancedDataGrid: expandItem()

[fumeng5]

Hi,

I'm trying to expand the first row of my AdvancedDataGrid column when it is 
loaded with my XML data. I've found plenty of examples online that show how to 
do it from a click event, but nothing on init of the grid. I've tried the 
initialize method, the setter of my dataProvider method but they all give me a 
range out of bounds error. 

Here's my function:

private function expandRow():void{
                                // Expand the first row of the ADG
                                var obj:Object = gc.getRoot(); 
                                var temp:Object = 
ListCollectionView(obj).getItemAt(0); 
                                grid.expandItem(temp,true);
                                grid.validateNow();
                        }

Anyone know the proper event to trigger this? 

Thank you,

Matt