Programmatic Multi_Col Grouping Problem

[stephen]

hey! guys:
 I created a datatable by code and set it to gridView's itemsource, everything looks good ,I could grouping cols my drag it to group panel.
then I created a button, in button's behind code, I created some group descriptors and added them into grid's group descriptors, Oops,
the problem is coming , the grid is not grouped as I expected, some rows were missing. 
  After I deleted the group cols by closing the grouping button and drag cols into group panel, the group is ok again.

GroupDescriptor descriptor1 = new GroupDescriptor();
descriptor1.Member = "Country";
descriptor1.SortDirection = ListSortDirection.Ascending;
this.gridView.GroupDescriptors.Add(descriptor1) ;

GroupDescriptor descriptor2 = new GroupDescriptor();
descriptor2.Member = "Name";
descriptor2.SortDirection = ListSortDirection.Ascending;
this.gridView.GroupDescriptors.Add(descriptor2) ;

The codes is same as demo. Did I miss something ?

[stephen]

Resolved myself, just because I missed something.

            GroupDescriptor descriptor = new GroupDescriptor();

            descriptor.Member = "ContactName";

            descriptor.SortDirection = ListSortDirection.Ascending;

            descriptor.DisplayContent = "ContactName";

            descriptor.MemberType = typeof(string);

           // this.gvList.GroupDescriptors.Add(descriptor);

descriptor.MemberType = typeof(string);