Timeline.DesiredFrameRate 附加屬性

定義

命名空間:

System.Windows.Media.Animation

組件:

PresentationCore.dll

取得或設定此時刻表及其子時刻表理想的畫面播放速率。

see GetDesiredFrameRate, and SetDesiredFrameRate

see GetDesiredFrameRate, and SetDesiredFrameRate

see GetDesiredFrameRate, and SetDesiredFrameRate

範例

下列範例使用 DesiredFrameRate 屬性，將數個動畫限制為每秒 10 個畫面。

<!-- DesiredFrameRateExample.xaml
     This example shows how to use the DesiredFrameRate property. 
     Two DrawingBrushes are animated. The desired frame rate is
     set on one group of animations but not the other, for comparison. -->
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  WindowTitle="DesiredFrameRate Example" Background="White">
  <Page.Resources>
  
    <!-- The Drawing used by the animated DrawingBrush. -->
    <DrawingGroup x:Key="CheckerDrawing">
      <GeometryDrawing Brush="White">
        <GeometryDrawing.Geometry>
          <RectangleGeometry Rect="0,0,100,100" />
        </GeometryDrawing.Geometry>
      </GeometryDrawing>
      <GeometryDrawing Brush="Gray">
        <GeometryDrawing.Geometry>
          <RectangleGeometry Rect="0,0,50,50" />
        </GeometryDrawing.Geometry>
      </GeometryDrawing>
      <GeometryDrawing Brush="Gray">
        <GeometryDrawing.Geometry>
          <RectangleGeometry Rect="50,50,50,50" />
        </GeometryDrawing.Geometry>
      </GeometryDrawing>        
    </DrawingGroup>
  </Page.Resources>

  <StackPanel Margin="10">  
    <Rectangle 
      Width="200" Height="200" Margin="10"
      Stroke="Black" StrokeThickness="1" >
      <Rectangle.Fill>
        <DrawingBrush 
          Drawing="{StaticResource CheckerDrawing}"
          Viewport="0,0,50,50" 
          ViewportUnits="Absolute"
          TileMode="Tile"> 
          <DrawingBrush.RelativeTransform>
            <TransformGroup>
              <RotateTransform 
                x:Name="AnimatedRotateTransform1"
                CenterX="0.5" CenterY="0.5" />
              <ScaleTransform
                x:Name="AnimatedScaleTransform1"
                CenterX="0.5" CenterY="0.5" />
            </TransformGroup>
          </DrawingBrush.RelativeTransform>
        </DrawingBrush> 
      </Rectangle.Fill>
      <Rectangle.Triggers>
        <EventTrigger RoutedEvent="Rectangle.Loaded">
          <BeginStoryboard>
          
            <!-- Set the desired framerate on the root timeline. 
                 The animations that belong to this storyboard
                 will be limited to 10 frames per second. -->
            <Storyboard Timeline.DesiredFrameRate="10">
              <DoubleAnimation 
                Storyboard.TargetName="AnimatedRotateTransform1"
                Storyboard.TargetProperty="Angle"
                From="0" To="360" 
                Duration="0:1:00" 
                AutoReverse="True"
                RepeatBehavior="Forever"
                />
              <DoubleAnimation 
                Storyboard.TargetName="AnimatedScaleTransform1"
                Storyboard.TargetProperty="ScaleX"
                From="1" To="5" 
                Duration="0:0:30" 
                AutoReverse="True"
                RepeatBehavior="Forever"
                />
              <DoubleAnimation 
                Storyboard.TargetName="AnimatedScaleTransform1"
                Storyboard.TargetProperty="ScaleY"
                From="1" To="5" 
                Duration="0:0:45" 
                AutoReverse="True"
                RepeatBehavior="Forever"
                />               
            </Storyboard>
          </BeginStoryboard>
        </EventTrigger>
      </Rectangle.Triggers>
    </Rectangle>
 
    <Rectangle 
      Width="200" Height="200" Margin="10"
      Stroke="Black" StrokeThickness="1">
      <Rectangle.Fill>
        <DrawingBrush 
          Drawing="{StaticResource CheckerDrawing}"
          Viewport="0,0,50,50" 
          ViewportUnits="Absolute"
          TileMode="Tile">
          <DrawingBrush.RelativeTransform>
            <TransformGroup>
              <RotateTransform 
                x:Name="AnimatedRotateTransform2"
                CenterX="0.5" CenterY="0.5" />
              <ScaleTransform
                x:Name="AnimatedScaleTransform2"
                CenterX="0.5" CenterY="0.5" />
            </TransformGroup>
          </DrawingBrush.RelativeTransform>
        </DrawingBrush> 
      </Rectangle.Fill>
      <Rectangle.Triggers>
        <EventTrigger RoutedEvent="Rectangle.Loaded">
          <BeginStoryboard>
          
            <!-- The animations that belong to this storyboard
                 will run at full speed. -->
            <Storyboard>
              <DoubleAnimation 
                Storyboard.TargetName="AnimatedRotateTransform2"
                Storyboard.TargetProperty="Angle"
                From="0" To="360" 
                Duration="0:1:00" 
                AutoReverse="True"
                RepeatBehavior="Forever"
                />
              <DoubleAnimation 
                Storyboard.TargetName="AnimatedScaleTransform2"
                Storyboard.TargetProperty="ScaleX"
                From="1" To="5" 
                Duration="0:0:30" 
                AutoReverse="True"
                RepeatBehavior="Forever"
                />
              <DoubleAnimation 
                Storyboard.TargetName="AnimatedScaleTransform2"
                Storyboard.TargetProperty="ScaleY"
                From="1" To="5" 
                Duration="0:0:45" 
                AutoReverse="True"
                RepeatBehavior="Forever"
                />               
            </Storyboard>
          </BeginStoryboard>
        </EventTrigger>
      </Rectangle.Triggers>      
    </Rectangle> 
  
  
  </StackPanel>
  
    


</Page>

備註

使用這個屬性來定義應該執行動畫的特定畫面播放速率。  這只是指導方針，而且不是保證的值。 此屬性有兩個主要用途：

• 限制緩慢移動的背景類型動畫處理資源數量，而不需要高度精確度的背景類型動畫。 這可藉由在時程表上設定小型畫面播放速率值來達成。

• 減少在快速移動水準動畫上卸載的視覺影響。 這可以藉由在時間軸上設定高畫面播放速率值來達成。

此屬性只能在根時程表上設定。

另請參閱

• 動畫概觀