[flexcoders] how

[btc132]

hello all 
I coding in AdvandDatagrid, but i can't to get data from a column in it.

I wrote:
[Bindable]
private var npupdate:ArrayCollection;
for(var i:int = 0; i < nounphrasesArray.length; i++)
{
        var obj:Object = {object:nounphrasesArray[i]};  
        NPresults.addItem(obj);
}
var adg:AdvancedDataGrid = new AdvancedDataGrid;                        
        adg.dataProvider = NPresults;                   
        adg.editable = "true";
var col1:AdvancedDataGridColumn = new AdvancedDataGridColumn();
        col1.editable = false;
        col1.minWidth = 210;
        col1.headerText = "Obect";                                      
        col1.dataField = "object";
        col1.wordWrap = true;
var col2:AdvancedDataGridColumn = new AdvancedDataGridColumn();
        col2.minWidth = 450;
        col2.headerText = "DEFINITION";
        col2.dataField = "definition";
        col2.wordWrap = true;   
        col2.addEventListener(Event.CHANGE, selectedItemchanged);
adg.displayItemsExpanded = true;                        
adg.groupedColumns = [col1,col2];
private function selectedItemchanged(event:Event):void
{
                
}

 Now, i want that, after user edit data to column 2 (col2), data in column 2 
will store in a matrix that i declared.
 You can help me to process it
thanks