private void LayoutRoot_ManipulationDelta(object sender, ManipulationDeltaRoutedEventArgs e)
{
// 2. Get the % value of how much the finger has moved based on the height of the root Grid.
var ratio = Math.Abs(e.Cumulative.Translation.Y) / LayoutRoot.ActualHeight;
var currentTime = SlideUpAnimation.Duration.TimeSpan.TotalMilliseconds * ratio;
// 3. 'Scrub' the animation - This is the Seek method that I think is missing in
// Composition's KeyFrameAnimation & CompositionScopedBatch.
SlideUpAnimation.Seek(TimeSpan.FromMilliseconds(currentTime));
}
private void LayoutRoot_ManipulationCompleted(object sender, ManipulationCompletedRoutedEventArgs e)
{
// 4. Resume the animation to finish it off smoothly.
SlideUpAnimation.Resume();
}
// The SlideUpAnimation Storyboard contains a number of keyframes that do the following -
// * Change the Offset Y of the TopPane;
// * Change the Opacity of the TopPane;
// * Change the Scale X & Y of the Marker;
// * Change the Color of the Marker.
private void LayoutRoot_ManipulationStarting(object sender, ManipulationStartingRoutedEventArgs e)
{
// 1. Start and pause the animation immediately.
SlideUpAnimation.Begin();
SlideUpAnimation.Pause();
}