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PointAnimation

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Animates the value of a Point property between two target values by using linear interpolation over a specified Duration.

<PointAnimation   .../>

Managed Equivalent

PointAnimation

Remarks

An animation updates the value of a property over a period of time. An animation effect can be subtle, such as moving a Shape object a few pixels left or right, or dramatic, such as enlarging an object to 200 times its original size while spinning it and changing its color. To create an animation, you associate an animation with an object's property value.

The PointAnimation class creates a transition between two target values. To set the target values, use the object's From, To, and By properties. The following table summarizes how you can use the From, To, and By properties together or separately to determine an animation's target values.

Properties specified

Resulting behavior

From

The animation progresses from the value of the From property to the base value of the property being animated.

From and To

The animation progresses from the value of the From property to the value of the To property.

From and By

The animation progresses from the value of the From property to the value specified by the sum of the From and By properties.

To

The animation progresses from the animated property's base value or a previous animation's output value to the value of the To property.

By

The animation progresses from the base value of the property being animated or a previous animation's output value to the sum of that value and the value of the By property.

If you set both the To and By properties, the To property takes precedence and the By property is ignored.

To use other interpolation methods or to animate between more than two target values, use the PointAnimationUsingKeyFrames object.

For more information on basic concepts, see Animation Overview. Note that the Animation Overview topic is written primarily for users of the managed API, and may not have code examples or specific information that address the JavaScript model scenarios.

Example

The following example shows how to use a PointAnimation to animate the Center property of an EllipseGeometry object.

<Canvas
  xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
  Width="400" Height="300">
  <Path Fill="Blue">
    <Path.Data>

      <!-- Describes an ellipse. -->
      <EllipseGeometry x:Name="MyAnimatedEllipseGeometry"
       Center="200,100" RadiusX="15" RadiusY="15" />
    </Path.Data>

    <Path.Triggers>
      <EventTrigger RoutedEvent="Path.Loaded">
        <BeginStoryboard>
          <Storyboard>

            <!-- Animate the center point of the ellipse from 100,300
                 to 400,100 over 5 seconds. -->
            <PointAnimation
              Storyboard.TargetProperty="Center"
              Storyboard.TargetName="MyAnimatedEllipseGeometry"
              Duration="0:0:5" 
              From="100,300"
              To="400,100"
              RepeatBehavior="Forever" />

          </Storyboard>
        </BeginStoryboard>
      </EventTrigger>
    </Path.Triggers> 
  </Path>
</Canvas>

See Also

Reference

Point