public ParentComboBox()
{
DrawMode = DrawMode.OwnerDrawFixed;
DropDownStyle = ComboBoxStyle.DropDownList;
this.DrawItem += new DrawItemEventHandler(this.comboBoxParents_DrawItem);
this.DropDownClosed += new System.EventHandler(this.comboBoxParents_DropDownClosed);
tt = new ToolTip();
}