The GridControl allows you to display summary information about groups of rows or individual data columns. For example, you can display the number of records, the minimum or maximum value, etc. This summary information is called data summary.
Private Sub view_CellValueChanged(ByVal sender As Object, ByVal e As DevExpress.Xpf.Grid.CellValueChangedEventArgs)
The GridControl does not update its summaries if you modify the control's data source directly (without using the control's UI). Set the DataControlBase.AllowLiveDataShaping property to true to make the control recalculate summaries when the data source changes.
Optimized Summary Recalculation
The GridControl can use an optimized summary recalculation mechanism, which processes only changed data records if an update is needed. As a result, the time required to update summary values does not depend on the number of records.