mmihevc said:

Grouping information is contained in the SortedFields collection as part of the FieldLayout.  Once a sort has been added though, you can not change it so you will need to remove it and add a new instance.  

 

 if (!XamDataGrid1.FieldLayouts[0].SortedFields.Contains("Market Price"))
 {

               XamDataGrid1.FieldLayouts[0].SortedFields.Add(new FieldSortDescription
                                                                    {
                                                                        FieldName = "Market Price",
                                                                        IsGroupBy= true
                                                                    });

}
else
{
                XamDataGrid1.FieldLayouts[0].SortedFields.Remove(XamDataGrid1.FieldLayouts[0].SortedFields["Market Price"]);
                XamDataGrid1.FieldLayouts[0].SortedFields.Add(new FieldSortDescription
                                                                    {
                                                                        FieldName = "Market Price",
                                                                        IsGroupBy = true
                                                                    });
}

 

Are we sure this actually works?  Intellisense does not confirm the presence of ".SortedFields".   While converting to VB, I can not make this example work at all.  I am using the Express version, and I suppose it is possible that is the issue.  Can anyone confirm?

 yepp, it works, thx for posting