Bug 412728

Using the following code:

--- START ----

using System;
using System.Drawing;
using System.Windows.Forms;

class ListBoxBug : Form {

	public ListBoxBug () {
		ListBox list = new ListBox ();
		string []range = { "A", "B", "C", "D", "E", "F", "G","H", "I", "J", "K", "L", "M" };
        	list.Items.AddRange (range);
		list.Size = new Size (100, 100);
		list.Location = new Point (1, 1);

		Button button = new Button ();
		button.Text = "click me";
		button.Click += delegate (object sender, EventArgs args) {
			list.TopIndex = 10;
		};
		button.Size = new Size (100, 25);
		button.Location = new Point (110, 1);

		Controls.Add (list);
		Controls.Add (button);

		Size = new Size (250, 200);
	}

	public static void Main (string []args) {
		Application.Run (new ListBoxBug ());
	}
}

---- END ---

Clicking "click me" button will change TopIndex and the VScrollbar will be moved, however isn't updated correctly, see attached image for more information.

This seems to affect ListControl-based controls, such as ListBox and CheckedListBox.