private void ItemContainer_Loaded(object sender, RoutedEventArgs e)
{
var itemsPanel = (ItemsStackPanel)ActivityList.ItemsPanelRoot;
var itemContainer = (ListViewItem)sender;
var itemIndex = ActivityList.IndexFromContainer(itemContainer);
var uc = itemContainer.ContentTemplateRoot as FrameworkElement;
var childPanel = uc.FindName("ActivityListItemPanel") as RelativePanel;
// Don't animate if we're not in the visible viewport
if (itemIndex >= itemsPanel.FirstVisibleIndex && itemIndex <= itemsPanel.LastVisibleIndex)
{
var itemVisual = ElementCompositionPreview.GetElementVisual(uc);
float width = (float)childPanel.RenderSize.Width;
float height = (float)childPanel.RenderSize.Height;
itemVisual.Size = new Vector2(width, height);
itemVisual.CenterPoint = new Vector3(width / 2, height / 2, 0f);
itemVisual.Scale = new Vector3(1, 1, 1); // new Vector3(0.25f, 0.25f, 0);
itemVisual.Opacity = 0f;
itemVisual.Offset = new Vector3(0, 100, 0);
var relativeIndex = itemIndex - itemsPanel.FirstVisibleIndex;
// Create KeyFrameAnimations
KeyFrameAnimation offsetAnimation = Compositor.CreateScalarKeyFrameAnimation();
offsetAnimation.InsertExpressionKeyFrame(1f, "0");
offsetAnimation.Duration = TimeSpan.FromMilliseconds(1250);
offsetAnimation.DelayTime = TimeSpan.FromMilliseconds(relativeIndex * 100);
Vector3KeyFrameAnimation scaleAnimation = Compositor.CreateVector3KeyFrameAnimation();
scaleAnimation.InsertKeyFrame(0, new Vector3(1f, 1f, 0f));
scaleAnimation.InsertKeyFrame(0.1f, new Vector3(0.05f, 0.05f, 0.05f));
scaleAnimation.InsertKeyFrame(1f, new Vector3(1f, 1f, 0f));
scaleAnimation.Duration = TimeSpan.FromMilliseconds(1000);
scaleAnimation.DelayTime = TimeSpan.FromMilliseconds(relativeIndex * 100);
KeyFrameAnimation fadeAnimation = Compositor.CreateScalarKeyFrameAnimation();
fadeAnimation.InsertExpressionKeyFrame(1f, "1");
fadeAnimation.Duration = TimeSpan.FromMilliseconds(500);
fadeAnimation.DelayTime = TimeSpan.FromMilliseconds(relativeIndex * 100);
// Start animations
itemVisual.StartAnimation("Offset.Y", offsetAnimation);
itemVisual.StartAnimation("Scale", scaleAnimation);
itemVisual.StartAnimation("Opacity", fadeAnimation);
}
itemContainer.Loaded -= ItemContainer_Loaded;
}