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DiscreteColorKeyFrame Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Animates from the Color value of the previous key frame to its own Value using discrete values.

Inheritance Hierarchy

System.Object
  System.Windows.DependencyObject
    System.Windows.Media.Animation.ColorKeyFrame
      System.Windows.Media.Animation.DiscreteColorKeyFrame

Namespace:  System.Windows.Media.Animation
Assembly:  System.Windows (in System.Windows.dll)

Syntax

'Declaration
Public NotInheritable Class DiscreteColorKeyFrame _
    Inherits ColorKeyFrame

public sealed class DiscreteColorKeyFrame : ColorKeyFrame

<DiscreteColorKeyFrame .../>

The DiscreteColorKeyFrame type exposes the following members.

Constructors

  Name Description
Public methodSupported by Silverlight for Windows Phone DiscreteColorKeyFrame Initializes a new instance of the DiscreteColorKeyFrame class.

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Properties

  Name Description
Public propertySupported by Silverlight for Windows Phone Dispatcher Gets the Dispatcher this object is associated with. (Inherited from DependencyObject.)
Public propertySupported by Silverlight for Windows Phone KeyTime Gets or sets the time at which the key frame's target Value should be reached. (Inherited from ColorKeyFrame.)
Public propertySupported by Silverlight for Windows Phone Value Gets or sets the key frame's target value. (Inherited from ColorKeyFrame.)

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Methods

  Name Description
Public methodSupported by Silverlight for Windows Phone CheckAccess Determines whether the calling thread has access to this object. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ClearValue Clears the local value of a dependency property. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows Phone Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetAnimationBaseValue Returns any base value established for a Silverlight dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetType Gets the Type of the current instance. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetValue Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject.)
Protected methodSupported by Silverlight for Windows Phone MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone ReadLocalValue Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone SetValue Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ToString Returns a string that represents the current object. (Inherited from Object.)

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Remarks

This class is used as part of a ColorKeyFrameCollection in conjunction with a ColorAnimationUsingKeyFrames to animate a Color property value along a set of key frames.

A key frame defines a segment of the ColorAnimationUsingKeyFrames to which it belongs. Each key frame has a target Value and a KeyTime. The KeyTime specifies the time at which the key frame's Value should be reached. A key frame animates from the target value of the previous key frame to its own target value. It starts when the previous key frame ends and ends when its own key time is reached.

Discrete key frames such as DiscreteColorKeyFrame create sudden "jumps" between values (no interpolation). In other words, the animated property does not change until the key frame's key time is reached, at which point the animated property goes suddenly to the target value.

Examples

The following example uses the ColorAnimationUsingKeyFrames class to animate the Background property of a StackPanel. This animation uses three key frames in the following manner:

  1. During the first two seconds, LinearColorKeyFrame gradually changes the color from green to red. Linear key frames like LinearColorKeyFrame create a smooth linear transition between values.

  2. During the end of the next half second, DiscreteColorKeyFrame quickly changes the color from red to yellow. Discrete key frames like DiscreteColorKeyFrame create sudden changes between values; the animation occurs quickly and has no interpolation between values at all.

  3. During the final two seconds, SplineColorKeyFrame changes the color again, this time from yellow back to green. Spline key frames like SplineColorKeyFrame create a variable transition between values according to the values of the KeySpline property. A KeySpline provides a way to alter the relationship of time versus value during the animation duration to be nonlinear, and in particular the relationship can be a curve that would be difficult to produce with individual key frames. In this example, the change in color begins slowly and speeds up exponentially toward the end of the time segment.

Run this sample

<StackPanel Background="White" x:Name="myStackPanel"
            Loaded="Start_Animation">
    <StackPanel.Resources>
        <Storyboard x:Name="colorStoryboard">
            <ColorAnimationUsingKeyFrames BeginTime="00:00:00" 
             Storyboard.TargetName="myStackPanel" 
             Storyboard.TargetProperty="(Panel.Background).(SolidColorBrush.Color)">

                <!-- Go from green to red in the first 2 seconds. LinearColorKeyFrame creates
        a smooth, linear animation between values. -->
                <LinearColorKeyFrame Value="Red" KeyTime="00:00:02" />

                <!-- In the next half second, go to yellow. DiscreteColorKeyFrame creates a 
        sudden jump between values. -->
                <DiscreteColorKeyFrame Value="Yellow" KeyTime="00:00:2.5" />

                <!-- In the final 2 seconds of the animation, go from yellow back to green. SplineColorKeyFrame 
        creates a variable transition between values depending on the KeySpline property. In this example,
        the animation starts off slow but toward the end of the time segment, it speeds up exponentially.-->
                <SplineColorKeyFrame Value="Green" KeyTime="00:00:4.5" KeySpline="0.6,0.0 0.9,0.00" />

            </ColorAnimationUsingKeyFrames>
        </Storyboard>
    </StackPanel.Resources>
</StackPanel>

' Start the animation when the object loads
Private Sub Start_Animation(ByVal sender As Object, ByVal e As EventArgs)
    colorStoryboard.Begin()
End Sub

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

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.