//Show circular Progressing Indicator private void ShowProgressBar() { DoubleAnimation fadeOut = Animations.FadeOut; fadeOut.Completed += delegate { OkButton.Visibility = Visibility.Collapsed; CircularProgressBar.Visibility = Visibility.Visible; CircularProgressBar.BeginAnimation(OpacityProperty, Animations.FadeIn); }; OkButton.BeginAnimation(OpacityProperty, fadeOut); }