Hi,

You won't find it on ScrollBarLook, because that area is not part of the scrollbars.

It doesn't look like the grid has any appearances that will affect this area, but it can by styled using AppStylist. This looks like something of an oversight to me. The grid should really have a property for this, so I'm going to forward this thread over to Infragistics Developer Support and ask them to write this up as a bug.

For now, if you just want to change the color of this area, the easiest thing to do would be to use AppStylist or a DrawFilter.

Here's a quick sample DrawFilter to show you how to do it:

    public class MyDrawFilter : IUIElementDrawFilter
    {
        #region IUIElementDrawFilter Members

        bool IUIElementDrawFilter.DrawElement(DrawPhase drawPhase, ref UIElementDrawParams drawParams)
        {
            switch (drawPhase)
            {
                case DrawPhase.BeforeDrawBackColor:
                    if (drawParams.Element is ScrollbarIntersectionUIElement)
                    {
                        drawParams.AppearanceData.BackColor = Color.Red;
                    }
                    break;
            }

            return false;
        }

        DrawPhase IUIElementDrawFilter.GetPhasesToFilter(ref UIElementDrawParams drawParams)
        {
            if (drawParams.Element is ScrollbarIntersectionUIElement)
            {
                return DrawPhase.BeforeDrawBackColor;
            }

            return DrawPhase.None;
        }

        #endregion
    }