I add some columns in Page_Load,and want to set multicolumn header in these columns.

in Page_load

var dr = db.ExecuteReader("select id,name from tb_warehouse");
                while (dr.Read())
                {
                    var col = new UltraGridColumn(true)
                                  {
                                      BaseColumnName = ("Quantity" + dr["id"]),
                                      Key = ("Quantity" + dr["id"]),
                                      HeaderText = dr["name"].ToString(),
                                      DataType = "System.Decimal",
                                      AllowUpdate = AllowUpdate.Yes,
                                      Format = "###,###,###.##",
                                      Width = Unit.Pixel(60)
                                  };
                    col.CellStyle.HorizontalAlign = HorizontalAlign.Right;
                    j += 1;
                    col.Header.RowLayoutColumnInfo.OriginX = j;
                    uwgList.Columns.Insert(j, col);

                }
                dr.Close();

in InitializeLayout
            foreach (UltraGridColumn c in uwgList.DisplayLayout.Bands[0].Columns)
            {
                c.Header.RowLayoutColumnInfo.OriginY = 1;
            }
            var ch = new ColumnHeader(true);
            ch.Caption = "test";
            ch.RowLayoutColumnInfo.OriginX = 4;
            ch.RowLayoutColumnInfo.OriginY = 0;
            ch.RowLayoutColumnInfo.SpanX = uwgList.Columns.FromKey("sumQuantity").Index -
                                           uwgList.Columns.FromKey("unit").Index;
            e.Layout.Bands[0].HeaderLayout.Add(ch);

foreach (UltraGridColumn c in e.Layout.Bands[0].Columns)
            {
                if ((c.Index <= uwgList.Columns.FromKey("unit").Index) ||
                    (c.Index >= uwgList.Columns.FromKey("sumQuantity").Index))

                {
                    c.Header.RowLayoutColumnInfo.OriginY = 0;
                    c.Header.RowLayoutColumnInfo.SpanY = 2;                

}
            }

but these columns's header caption didn't display the "test".

why??