如何：指定演示图板动画之间的 HandoffBehavior
本示例演示如何指定演示图板动画之间的切换行为。 BeginStoryboard 的 HandoffBehavior 属性指定新动画如何与已经应用于属性的任何现有动画交互。
示例
下面的示例创建两个按钮，当鼠标光标移到这两个按钮上时，它们将变大，当鼠标光标移开时，它们将变小。 如果将鼠标移到一个按钮上然后快速移走光标，则在第一个动画完成之前将应用第二个动画。 当两个动画像这样重叠时，您可以看到 Compose 和 SnapshotAndReplace 的 HandoffBehavior 值之间存在差异。 如果值为 Compose，在出现动画重叠时，动画之间的过渡将较为平滑，而如果值为 SnapshotAndReplace，则会使新动画立即取代之前的重叠动画。
<Page
xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml">
<Page.Resources>
<!-- This Style specifies mouseover and mouseout behaviors. The button gets larger when
the cursor moves over it and smaller when the cursor moves away. Note that the same Properties
(ScaleX and ScaleY) are being targeted by both animations. The BeginStoryboard for each animation
uses a HandoffBehavior of "Compose" which causes the old animation to interpolate more gradually into
the new one. -->
<Style x:Key="ButtonWithCompose" TargetType="{x:Type Button}">
<Setter Property="Button.RenderTransform">
<Setter.Value>
<ScaleTransform CenterX="50" CenterY="50" ScaleX="1" ScaleY="1" />
</Setter.Value>
</Setter>
<Style.Triggers>
<EventTrigger RoutedEvent="Mouse.MouseEnter">
<EventTrigger.Actions>
<BeginStoryboard >
<Storyboard>
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleX" To="3" />
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleY" To="3" />
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
<EventTrigger RoutedEvent="Mouse.MouseLeave">
<EventTrigger.Actions>
<BeginStoryboard HandoffBehavior="Compose">
<Storyboard>
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleX" />
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleY" />
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
</Style.Triggers>
</Style>
<!-- For this button style, BeginStoryboard uses the default HandoffBehavior of "SnapShotAndReplace" -->
<Style x:Key="ButtonWithSnapShotAndReplace" TargetType="{x:Type Button}">
<Setter Property="Button.RenderTransform">
<Setter.Value>
<ScaleTransform CenterX="50" CenterY="50" ScaleX="1" ScaleY="1" />
</Setter.Value>
</Setter>
<Style.Triggers>
<EventTrigger RoutedEvent="Mouse.MouseEnter">
<EventTrigger.Actions>
<BeginStoryboard >
<Storyboard>
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleX" To="3" />
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleY" To="3" />
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
<EventTrigger RoutedEvent="Mouse.MouseLeave">
<EventTrigger.Actions>
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleX" />
<DoubleAnimation Duration="0:0:2" Storyboard.TargetProperty="RenderTransform.ScaleY" />
</Storyboard>
</BeginStoryboard>
</EventTrigger.Actions>
</EventTrigger>
</Style.Triggers>
</Style>
</Page.Resources>
<Canvas>
<Button Style="{StaticResource ButtonWithSnapShotAndReplace}" Canvas.Top="200" Canvas.Left="200" Width="100" Height="100">
SnapShotAndReplace
</Button>
<Button Style="{StaticResource ButtonWithCompose}" Canvas.Top="200" Canvas.Left="400" Width="100" Height="100">
Compose
</Button>
</Canvas>
</Page>