protected override void OnNavigatedFrom(NavigationEventArgs e)
{
this.navigationHelper.OnNavigatedFrom(e);
// Prepare backward transition connected animation
if (e.NavigationMode == NavigationMode.Back)
{
// Pre-fall creator has different image loading order
// unable to share same connected animation code without breaking the UI
if (ApiInformation.IsApiContractPresent("Windows.Foundation.UniversalApiContract", 5))
{
if (FlipView.SelectedIndex >= 0)
{
try
{
var container = FlipView.ContainerFromIndex(FlipView.SelectedIndex) as FlipViewItem;
var mainPreview = container.ContentTemplateRoot as Grid;
var srollViewer = mainPreview.Children.First() as ScrollViewer;
var imageGrid = srollViewer.Content as Grid;
// Prepare backward connected animation
var grid = VisualTreeHelper.GetChild(FlipView, 0) as Grid;
var scrollingHost = grid.Children.FirstOrDefault(o => o is ScrollViewer) as UIElement;
ConnectedAnimationService.GetForCurrentView().PrepareToAnimate("PreviewImage", imageGrid);
}
catch (Exception ex)
{
}
}
}
}
}
private void HandleConnectedAnimation()
{
// Pre-fall creator has different image loading order
// unable to share same connected animation code without breaking the UI
if (!ApiInformation.IsApiContractPresent("Windows.Foundation.UniversalApiContract", 5))
{
return;
}
try
{
var container = FlipView.ContainerFromIndex(FlipView.SelectedIndex) as FlipViewItem;
// Do not play the animation if the target flipview item is not actually in the middle
// even if the SelectedIndex is pointing it, there are chance that the UI component is still not in the correct position
var transform = container.TransformToVisual(FlipView);
Point absolutePosition = transform.TransformPoint(new Point(0, 0));
if ((int)absolutePosition.X != 0)
{
return;
}
var animation = ConnectedAnimationService.GetForCurrentView().GetAnimation("PreviewImage");
if (animation != null)
{
if (FlipView.SelectedIndex >= 0)
{
var mainPreview = container.ContentTemplateRoot as Grid;
var srollViewer = mainPreview.Children.First() as ScrollViewer;
var imageGrid = srollViewer.Content as Grid;
// Prepare backward connected animation
if (!animation.TryStart(imageGrid))
{
readyForConnectedAnimation = false;
}
else
{
readyForConnectedAnimation = true;
}
}
}
}
catch (Exception ex)
{
}
}
public void InitAnimation(InitOption Option)
{
if (compositor != null)
{
if (Option == InitOption.AroundImage)
{
for (int i = Flip.SelectedIndex > 2 ? Flip.SelectedIndex - 2 : 0; i < Flip.SelectedIndex + 2 && i < Flip.Items.Count; i++)
{
if (Flip.ContainerFromIndex(i) is UIElement Element)
{
var Visual = ElementCompositionPreview.GetElementVisual(Element);
CenterPointAnimation.SetReferenceParameter("visual", Visual);
Visual.StartAnimation("CenterPoint", CenterPointAnimation);
Visual.StopAnimation("Scale.X");
ScaleAnimation.SetReferenceParameter("visual", Visual);
Visual.StartAnimation("Scale.X", ScaleAnimation);
Visual.StartAnimation("Scale.Y", ScaleAnimation);
}
}
}
else
{
foreach (var Visual in from Item in Flip.Items
let Element = Flip.ContainerFromItem(Item) as UIElement
where Element != null
select ElementCompositionPreview.GetElementVisual(Element))
{
CenterPointAnimation.SetReferenceParameter("visual", Visual);
Visual.StartAnimation("CenterPoint", CenterPointAnimation);
Visual.StopAnimation("Scale.X");
ScaleAnimation.SetReferenceParameter("visual", Visual);
Visual.StartAnimation("Scale.X", ScaleAnimation);
Visual.StartAnimation("Scale.Y", ScaleAnimation);
}
}
}
}