Behavior Class

class MyGlyph : Glyph
{
    Control control;
    BehaviorService behaviorSvc;

    public MyGlyph(BehaviorService behaviorSvc, Control control) : 
        base(new MyBehavior())
    {
        this.behaviorSvc = behaviorSvc;
        this.control = control;
    }

    public override Rectangle Bounds
    {
        get
        {
            // Create a glyph that is 10x10 and sitting 
            // in the middle of the control.  Glyph coordinates 
            // are in adorner window coordinates, so we must map 
            // using the behavior service.
            Point edge = behaviorSvc.ControlToAdornerWindow(control);
            Size size = control.Size;
            Point center = new Point(edge.X + (size.Width / 2), 
                edge.Y + (size.Height / 2));

            Rectangle bounds = new Rectangle(
                center.X - 5,
                center.Y - 5,
                10,
                10);

            return bounds;
        }
    }

    public override Cursor GetHitTest(Point p)
    {
        // GetHitTest is called to see if the point is 
        // within this glyph.  This gives us a chance to decide 
        // what cursor to show.  Returning null from here means 
        // the mouse pointer is not currently inside of the glyph. 
        // Returning a valid cursor here indicates the pointer is 
        // inside the glyph, and also enables our Behavior property 
        // as the active behavior. 
        if (Bounds.Contains(p))
        {
            return Cursors.Hand;
        }

        return null;
    }

    public override void Paint(PaintEventArgs pe)
    {
        // Draw our glyph. It is simply a blue ellipse.
        pe.Graphics.FillEllipse(Brushes.Blue, Bounds);
    }

    // By providing our own behavior we can do something interesting 
    // when the user clicks or manipulates our glyph. 
    class MyBehavior : Behavior
    {
        public override bool OnMouseUp(Glyph g, MouseButtons button)
        {
            MessageBox.Show("Hey, you clicked the mouse here");
            return true; // indicating we processed this event.
        }
    }
}