/// <summary>
        /// Overrides should call RegisterHighlight to ensure proper registration of the Highlight.
        /// </summary>
        public override void AddHighlight(Run run, int index, int length)
        {
            HighlightAdorner adorner = new FlowDocumentScrollViewerHighlightAdorner(flowDocumentScrollViewer, run, index, length, scrollBarHighlightHandler.HorizontalScrollBarHeight, BodyHighlightAdornerBrush, BodyHighlightAdornerPen, BodyIterativeHighlightAdornerBrush, BodyIterativeHighlightAdornerPen);

            RegisterHighlight(new FlowDocumentScrollViewerHighlight(index, index + length, adorner, run));
        }
 /// <summary>
 /// Overrides should call RegisterHighlight to ensure proper registration of the Highlight.
 /// </summary>
 public override void AddHighlight(Run run, int index, int length)
 {
     HighlightAdorner adorner = new FlowDocumentScrollViewerHighlightAdorner(flowDocumentScrollViewer, run, index, length, scrollBarHighlightHandler.HorizontalScrollBarHeight, BodyHighlightAdornerBrush, BodyHighlightAdornerPen, BodyIterativeHighlightAdornerBrush, BodyIterativeHighlightAdornerPen);
     RegisterHighlight(new FlowDocumentScrollViewerHighlight(index, index + length, adorner, run));
 }