private static DoubleAnimation CreateAnimation(ViewFrame viewFrame, PageTransitionDirection direction)
{
var transitionTarget = viewFrame;
// 初始化 Effect
var effect = new TransitionSlideInEffect
{
Texture2 = new ImageBrush(TakeSnap(transitionTarget)),
Progress = 0
};
switch (direction)
{
case PageTransitionDirection.LeftToRight:
effect.SlideAmount = new Point(-1.0, 0.0);
break;
case PageTransitionDirection.RightToLeft:
effect.SlideAmount = new Point(1.0, 0.0);
break;
case PageTransitionDirection.TopToBottom:
effect.SlideAmount = new Point(0.0, -1.0);
break;
case PageTransitionDirection.BottomToTop:
effect.SlideAmount = new Point(0.0, 1.0);
break;
default:
throw new ArgumentOutOfRangeException(nameof(direction), direction, null);
}
transitionTarget.Effect = effect;
var doubleAnimation = new DoubleAnimation(0, 100, TimeSpan.FromMilliseconds(300))
{
EasingFunction = new PowerEase()
{
EasingMode = EasingMode.EaseOut
}
};
doubleAnimation.Completed += (sender, args) =>
{
transitionTarget.Effect = null;
};
return(doubleAnimation);
}
public static DoubleAnimation CheckOutAnimation([NotNull] this ViewFrame viewFrame, [CanBeNull] UIElement target)
{
if (viewFrame == null)
{
throw new ArgumentNullException(nameof(viewFrame));
}
// 如果 target 无法转换为 IPageTransitionAnimation，则表示其没有实现这个接口，返回空
// ReSharper disable once SuspiciousTypeConversion.Global
if (!(target is IPageTransitionAnimation animation))
{
return(null);
}
if (animation.InOutMode == PageTransitionMode.OnlyIn)
{
return(null);
}
return(CreateAnimation(viewFrame, animation.OutDirection));
}