HOW TO：設定動畫的持續時間

更新：2007 年 11 月

Timeline 代表一段時間，而這段時間的長度是由時刻表的 Duration 所決定。當 Timeline 過了持續期間後，就會停止播放。如果 Timeline 子時刻表，子時刻表也會停止播放。動畫的 Duration 會指定動畫從開始值轉換到結束值要用多少時間。

您可以將 Duration 指定為特定有限時間或是特殊值 (Automatic 或 Forever)。動畫的持續時間須為時間值，因為動畫必須永遠有定義的有限長度，否則動畫就不知道如何在其目標值之間轉換。容器時刻表 (TimelineGroup 物件，例如 Storyboard 和 ParallelTimeline) 的預設持續時間為 Automatic，這表示它們會在最後一個子系停止播放時自動結束。

在下列範例中，Rectangle 的寬度、高度和填滿色彩會顯示為動畫。持續時間會在動畫和容器時刻表上設定，所產生的動畫效果包括控制動畫的顯示速度以及使用容器時刻表的持續時間覆寫子時刻表的持續時間。

範例

<Page 
  xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation" 
  xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml">
  <StackPanel Margin="20">

    <Rectangle Width="100" Height="100" Name="myRectangle">
      <Rectangle.Fill>
        <SolidColorBrush x:Name="MyAnimatedBrush" Color="Black" />
      </Rectangle.Fill>
      <Rectangle.Triggers>

        <!-- Animates the rectangle fill to yellow and width to 300. -->
        <EventTrigger RoutedEvent="Rectangle.Loaded">
          <BeginStoryboard>

            <!-- By default, TimelineGroup objects like Storyboard and ParallelTimeline have 
            a Duration of "Automatic". A TimelineGroup's automatic duration encompasses its 
            last-ending child. In this example, there is only one child of the Storyboard, the
            ParallelTimeline, so when the ParallelTimeline ends, the Storyboard duration will
            automatically end. -->
            <Storyboard>

              <!-- This ParallelTimeline has overriden its default duration of "Automatic" with
              a finite duration of half a second. This will force this Timeline to end after half a
              second even though its child Timelines have a longer duration (2 and 4 seconds respectively). 
              This cuts off the animation prematurely and the rectangle's fill will not go all the way to 
              yellow nor will the rectangle width get all the way to 300. Again, the default duration of a
              ParallelTimeline is "Automatic" so if you remove the finite duration, the ParallelTimeline
              will wait for its child timelines to end before it ends. -->

              <!-- Note: To specify a finite time in XAML, use the syntax of "days:hours:seconds". As mentioned,
              this ParallelTimeline has a duration of half a second. -->
              <ParallelTimeline Duration="0:0:0.5">

                <!-- For Animation Timelines like DoubleAnimation, the duration is one factor that
                determines the rate at which an animation appears to progress. For example, the DoubleAnimation
                below that animates the rectangle height will complete in only one second while the animation
                that animates the width willwill complete in 2 seconds which is relatively fast compared to the DoubleAnimation
                which animates the rectangle width over 4 seconds. -->
                <DoubleAnimation
                  Storyboard.TargetName="myRectangle"
                  Storyboard.TargetProperty="Height"
                  To="300" Duration="0:0:1" />

                <DoubleAnimation
                  Storyboard.TargetName="myRectangle"
                  Storyboard.TargetProperty="Width"
                  To="300" Duration="0:0:4" />

                <ColorAnimation
                  Storyboard.TargetName="MyAnimatedBrush"
                  Storyboard.TargetProperty="Color"
                  To="Yellow" Duration="0:0:2" />

              </ParallelTimeline>
            </Storyboard>
          </BeginStoryboard>
        </EventTrigger>

      </Rectangle.Triggers>
    </Rectangle>
  </StackPanel>
</Page>

請參閱

概念

動畫概觀

參考

Duration