[flexcoders] Does Drag & Drop Only Update the DataProvider?

[Geoffrey]

I have a DataGrid that has a dataProvider bound to an ArrayCollection.

<code>
<mx:DataGrid id="dgEmployees"
   dataProvider="{__employees}"
   ...>
</code>

I also have another DataGrid (dgAllEmployees) that is within a popup,
which I use as a source for Drag & Drop operations to populate the
dgEmployee dataGrid.

What I've noticed is that when I drag & drop employees from the "all
employees" DataGrid to the "employees" DataGrid, it seems to only
update the dataProvider of dgEmployees, and not the ArrayCollection
__employees.  Why is this?

Below is a snip of my drag & drop code where it actually copies the
data.  This is a generic method that is used all over the application.
<code>
public static function doDragDrop( event:DragEvent ):void
{
        // Prevent the default event from happening.
        event.preventDefault();

        // Get drop target
        var dropTarget:DataGrid = DataGrid(event.currentTarget);
        
        // Get the dragged items from the drag initiator.
        var dropItems:Array = event.dragSource.dataForFormat("items") as Array;

        // Add each item to the drop target.
        for (var i:uint = 0; i < dropItems.length; i++)
        {
                var dest:IList = IList(dropTarget.dataProvider);
                if (!contains(dest, dropItems[i]))
                {
                        dest.addItem(dropItems[i]);
                }
        }
}
</code>

I think that I had event.preventDefault(); in there because it was
putting 2 of each dropped item in the dgEmployee DataGrid.  Might this
be messing something up?

Also, contains() is a custom method to compare the source items to
what's in the target's list to prevent duplicates.  Is there a better
way to do this?

Thanks in advance.
GT