public override void LoadView()
        {
            base.LoadView();

            PDFView pv = (View as PDFView);

            if (pv != null)
            {
                pv.AnnotatedText = _text;
            }
        }
        public override void ViewDidLoad()
        {
            base.ViewDidLoad();

            // previous page
            pdfToolbar.Items[2].Clicked += delegate {
                PDFView pdfV = View as PDFView;
                pdfV.PageNumber--;
            };

            // next page
            pdfToolbar.Items[3].Clicked += delegate {
                PDFView pdfView = View as PDFView;
                pdfView.PageNumber++;
            };

            // close
            pdfToolbar.Items[0].Clicked += delegate {
                this.DismissModalViewControllerAnimated(true);
            };
        }