private void treeList1_ShowFilterPopupCheckedListBox(object sender, FilterPopupCheckedListBoxEventArgs e)
 {
     if (e.Column.FieldName != "Department")
     {
         return;
     }
     // disable "(Select All)" item
     e.CheckedComboBox.SelectAllItemVisible = false;
 }
        private void gvDrawings_ShowFilterPopupCheckedListBox(object sender, FilterPopupCheckedListBoxEventArgs e)
        {
            if (e.Column == colStandartSize)
            {
                var items = new List<CheckedListBoxItem>();

                for (int i = 0; i < e.CheckedComboBox.Items.Count; i++)
                {
                    var item = e.CheckedComboBox.Items[i];
                    if (item.Value != null)
                    {
                        items.Add(item);
                    }
                }

                items = items.OrderBy(item => item.Value.ToString(), new StandartSizeComparer()).ToList();
                e.CheckedComboBox.Items.Clear();
                e.CheckedComboBox.Items.AddRange(items.ToArray());
            }
        }