protected virtual void HandleItemChecked(object sender, ItemCheckEventArgs e)
{
ToolStripCheckedListBox checkedList = sender as ToolStripCheckedListBox;
if (checkedList == null) return;
OLVColumn column = checkedList.Tag as OLVColumn;
if (column == null) return;
ObjectListView listView = column.ListView as ObjectListView;
if (listView == null) return;
// Deal with the "Select All" item if there is one
int selectAllIndex = checkedList.Items.IndexOf(SELECT_ALL_LABEL);
if (selectAllIndex >= 0)
HandleSelectAllItem(e, checkedList, selectAllIndex);
}