protected virtual void OnPlusPaint(object sender, ItemPaintEventArgs e)
        {
            Rectangle r = e.ClipRectangle;

            r.Inflate(-4, -4);
            DrawPlusSign(e.Graphics, r, expandedIn != null && expandedIn.Contains(e.List));
        }
		protected virtual void OnPlusPaint(object sender, ItemPaintEventArgs e)
		{
			Rectangle r = e.ClipRectangle;
			r.Inflate(-4, -4);
			DrawPlusSign(e.Graphics, r, expandedIn != null && expandedIn.Contains(e.List));
		}
		void OnIconPaint(object sender, ItemPaintEventArgs e)
		{
			if (content.Image != null) {
				e.Graphics.DrawImageUnscaled(content.Image, e.ClipRectangle);
			}
		}