Hi,

You could add an event handler to XamGrid's CellDoubleClicked event and expand the row:

        private void igGrid_CellDoubleClicked(object sender, CellClickedEventArgs e)
        {
            if (e.Cell is GroupByCell)
            {
                ExpandableRowBase row = ((ExpandableRowBase)e.Cell.Row);
                row.IsExpanded = !row.IsExpanded;
            }
        }

Hope this helps,