private void partName_listbox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (partName_listbox.SelectedIndex == -1)
            {
                MessageBox.Show("Select a Part Name!");
            }
            else
            {
                //pull batch names from the DB, then render the view for filtering
                SelectedPartName = partName_listbox.SelectedItem.ToString();
                GCIDB.Initialize();
                GCIDB.OpenConnection();
                batchNames = GCIDB.GetBatchNameList(SelectedPartName);
                batchName_listbox.ItemsSource = batchNames;

                System.ComponentModel.ICollectionView batchName_view = CollectionViewSource.GetDefaultView(batchName_listbox.ItemsSource);
                batchName_view.Filter = batchName_CustomFilter;
            }
        }