void InitOutlineViewAndButton()
{
// Extract the remaining views from our custom layout.
pdfOutlineView = FindViewById <PdfOutlineView> (Resource.Id.outlineView);
if (pdfOutlineView == null)
{
throw new IllegalStateException("Error while loading CustomFragmentActivity. The example layout was missing the outline view.");
}
var outlineViewListener = new DefaultOutlineViewListener(fragment);
pdfOutlineView.SetOnAnnotationTapListener(outlineViewListener);
pdfOutlineView.SetOnOutlineElementTapListener(outlineViewListener);
pdfOutlineView.SetBookmarkAdapter(new DefaultBookmarkAdapter(fragment));
var openOutlineButton = FindViewById <ImageView> (Resource.Id.openOutlineButton);
openOutlineButton.Click += (sender, e) => pdfOutlineView.Show();
openOutlineButton.SetImageDrawable(TintDrawable(openOutlineButton.Drawable, ContextCompat.GetColor(this, Resource.Color.pspdf__color_white)));
}
