PointAnimation class

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

Inheritance

Object

  DependencyObject

    Timeline

      PointAnimation

Syntax

public sealed class PointAnimation : Timeline

<PointAnimation .../>

Attributes

ActivatableAttribute(NTDDI_WIN8)

MarshalingBehaviorAttribute(Agile)

StaticAttribute(Windows.UI.Xaml.Media.Animation.IPointAnimationStatics, NTDDI_WIN8)

ThreadingAttribute(Both)

VersionAttribute(NTDDI_WIN8)

WebHostHiddenAttribute()

Members

The PointAnimation class has these types of members:

• Constructors
• Events
• Methods
• Properties

Constructors

The PointAnimation class has these constructors.

Events

The PointAnimation class has these events.

Methods

The PointAnimation class has these methods. It also inherits methods from the Object class.

Properties

The PointAnimation class has these properties.

Remarks

Use PointAnimation to animate the property value of any dependency property that is of type Point.

Linear interpolation for a Point means that X and Y values are treated as a number and the interpolation is simply a mathematical operation.

Sometimes you'll need to use indirect property targeting in order to target a sub-property of another object that's the value of a property on the target. For example, in order to animate parts of a PathGeometry, you need to reference some of the intermediate object-property values, until the last step in the indirect property path is truly a Point value. For more info on indirect property targeting and other storyboarded animation concepts, see Storyboarded animations or Property path syntax.

A PointAnimation typically has at least one of the From, By or To properties set, but never all three.

• From only: The animation progresses from the value specified by the From property to the base value of the property being animated.
• From and To: The animation progresses from the value specified by the From property to the value specified by the To property.
• From and By: The animation progresses from the value specified by the From property to the value specified by the sum of the From and By properties.
• To only: The animation progresses from the animated property's base value or a previous animation's output value to the value specified by the To property.
• By only: 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 specified by the By property.

The From, By or To properties of a PointAnimation aren't a Point value. Instead these are a Nullable for Point. The default value for these is null, not an uninitialized structure. That null value is how the animation system distinguishes that you haven't specifically set a value. Visual C++ component extensions (C++/CX) doesn't have a Nullable type, so it uses IReference instead.

Examples

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

<Canvas Width="450" Height="350">
    <Canvas.Resources>
        <Storyboard x:Name="myStoryboard">

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

        </Storyboard>
    </Canvas.Resources>
    <Path Fill="Blue" Loaded="Start_Animation">
        <Path.Data>

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

// Start the animation when the object loads
private void Start_Animation(object sender, RoutedEventArgs e)
{
    myStoryboard.Begin();
}

Requirements

See also

Storyboarded animations

XAML animation sample

Timeline

Point

PointAnimationUsingKeyFrames

Build date: 12/4/2012