void fg_AfterDataRefresh(object sender, System.ComponentModel.ListChangedEventArgs e)
{
// total on Sale Amount
int totalOn = _flex.Cols["Sale Amount"].SafeIndex;
string caption = "Total for {0}";
// don't update the screen while calculating the totals
_flex.BeginUpdate();
// calculate three levels of totals
_flex.Subtotal(AggregateEnum.Sum, 0, 1, totalOn, caption);
_flex.Subtotal(AggregateEnum.Sum, 1, 2, totalOn, caption);
_flex.Subtotal(AggregateEnum.Sum, 2, 3, totalOn, caption);
_flex.Tree.Show(2);
// auto-size the grid to accommodate the tree
_flex.AutoSizeCols(1, 1, 1000, 3, 30, AutoSizeFlags.IgnoreHidden);
// restore screen updates
_flex.EndUpdate();
}