public static void SetDataSource(ListView lv, DataSet ds)

        {

            DataSet preds = (DataSet)lv.DataContext;

            if (preds == null) // first set datacontext

            {

                preds = ds;

                lv.DataContext = preds;

            }

            else // reset data context, we don't change the datacontext object , but change data rows

            {

                DataTable tb = preds.Tables[0];

                tb.Clear();

                tb.Dispose();

                foreach (DataRow dr in ds.Tables[0].Rows)

                {

                    tb.ImportRow(dr);

                }

                lv.DataContext = preds;

                ds.Dispose();

                ds = null;

            }

        }

        public static void AddDataRowToDataSource(ListView lv, DataRow dr)

        {

            DataSet ds = (DataSet)lv.DataContext;

            if (ds == null)

            {

                return;

            }

            else

            {

                DataTable tb = ds.Tables[0];

                tb.ImportRow(dr);

                lv.DataContext = ds;

            }

        }