private ObservableCollection <WarehouseLocation> BuildWarehouseLocationDropDown()
        {
            List <WarehouseLocation> list = new List <WarehouseLocation>();

            list = _serviceAgent.GetWarehouseLocationsReadOnly(ClientSessionSingleton.Instance.CompanyID).ToList();
            list.Add(new WarehouseLocation());
            list.Sort((x, y) => string.Compare(x.Name, y.Name));

            return(new ObservableCollection <WarehouseLocation>(list));
        }