private void updateImage()
{
var s = _urnList[_urnIndex];
var imageSource = new UriImageSource {
Uri = new Uri("http://www.loomisexpress.com/ca/SavedSigImg/" + s)
};
CurrentImage.Source = imageSource;
ImageString.Text = imageSource.ToString();
URIEntry.Text = imageSource.Uri.Segments.Last();
}
