AdaptiveImage.cs

private void ImageFailed(object sender, ExceptionRoutedEventArgs e)
{
    this.ProgressIndicator.IsActive = false;
}

private void ImageOpened(object sender, RoutedEventArgs e)
{
    if (this.HiResImage != null)
    {
        this.LayoutRoot.Children.Remove(this.LowResImage);
        this.HiResImage.Visibility = Visibility.Visible;

        this.ProgressIndicator.IsActive = false;
    }
}