private void settingSecondaryItemListBoxControl_MouseMove(object sender, MouseEventArgs e) { CheckedListBoxControl listBoxControl = sender as CheckedListBoxControl; int index = listBoxControl.IndexFromPoint(new Point(e.X, e.Y)); if (index != -1) { string item = listBoxControl.GetItem(index) as string; toolTipController1.ShowHint(item, listBoxControl.PointToScreen(new Point(e.X, e.Y))); } else { toolTipController1.HideHint(); } }