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Timeline.DesiredFrameRate Attached Property

Definition

Gets or sets the desired frame rate for this timeline and its child timelines.

see GetDesiredFrameRate, and SetDesiredFrameRate
see GetDesiredFrameRate, and SetDesiredFrameRate
see GetDesiredFrameRate, and SetDesiredFrameRate

Examples

The following example uses the DesiredFrameRate property to limit several animations to 10 frames per second.

<!-- 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>

Remarks

Use this property to define a specific frame rate at which animations should run.  This is a guideline only, and is not a guaranteed value. This property has two primary uses:

  • Limiting the amount of processing resources for slow-moving, background type animations that do not require a high degree of fidelity. This can be achieved by setting a small frame rate value on the timeline.

  • Reducing the visual impact of tearing on fast-moving horizontal animations. This can be achieved by setting a high frame rate value on the timeline.

This property may only be set on a root timeline.

Applies to

See also