void atoz_order()
{
//this.activities_list._list.Items.SortDescriptions.Clear();
//this.activities_list._list.Items.SortDescriptions.Add(new SortDescription("username", ListSortDirection.Descending));
if (this.activities_list._list.Items.Count > 0)
configurations.SortItemGenericList(this.activities_list._list.Items,
true, false, false, configurations.activities_num_desc.Length, configurations.activities_date_desc.Length, atoz_asc, true);
//this.activities_list._list.Items.Refresh();
}