BooleanAnimationUsingKeyFrames Class
Assembly: PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
'Declaration <ContentPropertyAttribute("KeyFrames")> _ Public Class BooleanAnimationUsingKeyFrames _ Inherits BooleanAnimationBase _ Implements IKeyFrameAnimation, IAddChild 'Usage Dim instance As BooleanAnimationUsingKeyFrames
<BooleanAnimationUsingKeyFrames> KeyFrames </BooleanAnimationUsingKeyFrames>
A key frame animation's target values are defined by its KeyFrames property, which contains a collection of BooleanKeyFrame objects. Each BooleanKeyFrame defines a segment of the animation with its own target Value and KeyTime. When the animation runs, it progresses from one key value to the next at the specified key times.
This example shows how to animate the Boolean property value of a Button control by using key frames.
The following example uses the BooleanAnimationUsingKeyFrames class to animate the IsEnabled property of a Button control. All the key frames in this example use an instance of the DiscreteBooleanKeyFrame class. Discrete key frames like DiscreteBooleanKeyFrame create sudden jumps between values, that is, the movement of the animation is jerky.
// Demonstrates a BooleanAnimationUsingKeyFrames. The animation is used to // animate the IsEnabled property of a button. using System; using System.Windows; using System.Windows.Controls; using System.Windows.Shapes; using System.Windows.Media.Animation; using System.Windows.Media; namespace Microsoft.Samples.KeyFrameExamples { public class BooleanAnimationUsingKeyFramesExample : Page { public BooleanAnimationUsingKeyFramesExample() { Title = "BooleanAnimationUsingKeyFrames Example"; Background = Brushes.White; Margin = new Thickness(20); // Create a NameScope for this page so that // Storyboards can be used. NameScope.SetNameScope(this, new NameScope()); StackPanel myStackPanel = new StackPanel(); myStackPanel.Orientation = Orientation.Vertical; myStackPanel.Margin = new Thickness(20); // Create a TextBlock to introduce the example. TextBlock myTextBlock = new TextBlock(); myTextBlock.Text = "Click the button to animate its IsEnabled property" + " with aBooleanAnimationUsingKeyFrames animation."; myStackPanel.Children.Add(myTextBlock); // Create the Button that is the target of the animation. Button myButton = new Button(); myButton.Margin = new Thickness(200); myButton.Content = "Click Me"; myStackPanel.Children.Add(myButton); // Assign the Button a name so that // it can be targeted by a Storyboard. this.RegisterName( "AnimatedButton", myButton); // Create a BooleanAnimationUsingKeyFrames to // animate the IsEnabled property of the Button. BooleanAnimationUsingKeyFrames booleanAnimation = new BooleanAnimationUsingKeyFrames(); booleanAnimation.Duration = TimeSpan.FromSeconds(4); // All the key frames defined below are DiscreteBooleanKeyFrames. // Discrete key frames create sudden "jumps" between values // (no interpolation). Only discrete key frames can be used // for Boolean key frame animations. // Value at the beginning is false booleanAnimation.KeyFrames.Add( new DiscreteBooleanKeyFrame( false, // Target value (KeyValue) KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0.0))) // KeyTime ); // Value becomes true after the first second. booleanAnimation.KeyFrames.Add( new DiscreteBooleanKeyFrame( true, // Target value (KeyValue) KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1.0))) // KeyTime ); // Value becomes false after the 2nd second. booleanAnimation.KeyFrames.Add( new DiscreteBooleanKeyFrame( false, // Target value (KeyValue) KeyTime.FromTimeSpan(TimeSpan.FromSeconds(2.0))) // KeyTime ); // Value becomes true after the third second. booleanAnimation.KeyFrames.Add( new DiscreteBooleanKeyFrame( true, // Target value (KeyValue) KeyTime.FromTimeSpan(TimeSpan.FromSeconds(3.0))) // KeyTime ); // Value becomes false after 3 and half seconds. booleanAnimation.KeyFrames.Add( new DiscreteBooleanKeyFrame( false, // Target value (KeyValue) KeyTime.FromTimeSpan(TimeSpan.FromSeconds(3.5))) // KeyTime ); // Value becomes true after the fourth second. booleanAnimation.KeyFrames.Add( new DiscreteBooleanKeyFrame( true, // Target value (KeyValue) KeyTime.FromTimeSpan(TimeSpan.FromSeconds(4.0))) // KeyTime ); // Set the animation to target the IsEnabled property // of the object named "AnimatedButton". Storyboard.SetTargetName(booleanAnimation, "AnimatedButton"); Storyboard.SetTargetProperty( booleanAnimation, new PropertyPath(Button.IsEnabledProperty)); // Create a storyboard to apply the animation. Storyboard myStoryboard = new Storyboard(); myStoryboard.Children.Add(booleanAnimation); // Start the storyboard when the button is clicked. myButton.Click += delegate(object sender, RoutedEventArgs e) { myStoryboard.Begin(this); }; Content = myStackPanel; } } }
<!-- Demonstrates a BooleanAnimationUsingKeyFrames. The animation is used to animate the IsEnabled property of a button. --> <Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" WindowTitle="KeyFrameBoolean Animation Example"> <StackPanel Orientation="Vertical" Margin="20"> <TextBlock> Click the button to animate its IsEnabled property with a BooleanAnimationUsingKeyFrames animation. </TextBlock> <Button Name="myAnimatedButton" Margin="200">Click Me <Button.Triggers> <EventTrigger RoutedEvent="Button.Click"> <BeginStoryboard> <Storyboard> <BooleanAnimationUsingKeyFrames Storyboard.TargetName="myAnimatedButton" Storyboard.TargetProperty="IsEnabled" Duration="0:0:4" FillBehavior="HoldEnd"> <!-- All the key frames below are DiscreteBooleanKeyFrames. Discrete key frames create sudden "jumps" between values (no interpolation). Only discrete key frames can be used for Boolean key frame animations. --> <DiscreteBooleanKeyFrame Value="False" KeyTime="0:0:0" /> <DiscreteBooleanKeyFrame Value="True" KeyTime="0:0:1" /> <DiscreteBooleanKeyFrame Value="False" KeyTime="0:0:2" /> <DiscreteBooleanKeyFrame Value="True" KeyTime="0:0:3" /> <DiscreteBooleanKeyFrame Value="False" KeyTime="0:0:3.5" /> <DiscreteBooleanKeyFrame Value="True" KeyTime="0:0:4" /> </BooleanAnimationUsingKeyFrames> </Storyboard> </BeginStoryboard> </EventTrigger> </Button.Triggers> </Button> </StackPanel> </Page>
For the complete sample, see KeyFrame Animation Sample.
System.Windows.Threading.DispatcherObject
System.Windows.DependencyObject
System.Windows.Freezable
System.Windows.Media.Animation.Animatable
System.Windows.Media.Animation.Timeline
System.Windows.Media.Animation.AnimationTimeline
System.Windows.Media.Animation.BooleanAnimationBase
System.Windows.Media.Animation.BooleanAnimationUsingKeyFrames
Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.