private void TransitionChanged(object sender, SelectionChangedEventArgs e)
{
switch (_transition.SelectedIndex)
{
case 0:
_carousel.Transition = null;
break;
case 1:
_carousel.Transition = new PageSlide(TimeSpan.FromSeconds(0.25));
break;
case 2:
_carousel.Transition = new CrossFade(TimeSpan.FromSeconds(0.25));
break;
}
}