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title description ms.date ms.custom dev_langs helpviewer_keywords ms.assetid
Storyboards Overview
Organize and apply animations in storyboards. Use property-targeting syntax and combine timelines in Windows Presentation Foundation (WPF).
03/30/2017
devdivchpfy22
csharp
vb
Storyboard syntax [WPF]
syntax [WPF], Storyboard
timelines [WPF]
1a698c3c-30f1-4b30-ae56-57e8a39811bd

Storyboards Overview

This topic shows how to use xref:System.Windows.Media.Animation.Storyboard objects to organize and apply animations. It describes how to interactively manipulate xref:System.Windows.Media.Animation.Storyboard objects and describes indirect property targeting syntax.

Prerequisites

To understand this topic, you should be familiar with the different animation types and their basic features. For an introduction to animation, see the Animation Overview. You should also know how to use attached properties. For more information about attached properties, see the Attached Properties Overview.

What Is a Storyboard

Animations are not the only useful type of timeline. Other timeline classes are provided to help you organize sets of timelines, and to apply timelines to properties. Container timelines derive from the xref:System.Windows.Media.Animation.TimelineGroup class, and include xref:System.Windows.Media.Animation.ParallelTimeline and xref:System.Windows.Media.Animation.Storyboard.

A xref:System.Windows.Media.Animation.Storyboard is a type of container timeline that provides targeting information for the timelines it contains. A Storyboard can contain any type of xref:System.Windows.Media.Animation.Timeline, including other container timelines and animations. xref:System.Windows.Media.Animation.Storyboard objects enable you to combine timelines that affect a variety of objects and properties into a single timeline tree, making it easy to organize and control complex timing behaviors. For example, suppose you want a button that does these three things.

  • Grow and change color when the user selects the button.

  • Shrink away and then grow back to its original size when clicked.

  • Shrink and fade to 50 percent opacity when it becomes disabled.

In this case, you have multiple sets of animations that apply to the same object, and you want to play at different times, dependent on the state of the button. xref:System.Windows.Media.Animation.Storyboard objects enable you to organize animations and apply them in groups to one or more objects.

Where Can You Use a Storyboard

A xref:System.Windows.Media.Animation.Storyboard can be used to animate dependency properties of animatable classes (for more information about what makes a class animatable, see the Animation Overview). However, because storyboarding is a framework-level feature, the object must belong to the xref:System.Windows.NameScope of a xref:System.Windows.FrameworkElement or a xref:System.Windows.FrameworkContentElement.

For example, you could use a xref:System.Windows.Media.Animation.Storyboard to do the following:

  • Animate a xref:System.Windows.Media.SolidColorBrush (Non-framework element) that paints the Background of a Button (a type of xref:System.Windows.FrameworkElement),

  • Animate a xref:System.Windows.Media.SolidColorBrush (Non-framework element) that paints the fill of a xref:System.Windows.Media.GeometryDrawing (Non-framework element) displayed using an xref:System.Windows.Controls.Image (xref:System.Windows.FrameworkElement).

  • In code, animate a xref:System.Windows.Media.SolidColorBrush declared by a class that also contains a xref:System.Windows.FrameworkElement, if the xref:System.Windows.Media.SolidColorBrush registered its name with that xref:System.Windows.FrameworkElement.

However, you could not use a xref:System.Windows.Media.Animation.Storyboard to animate a xref:System.Windows.Media.SolidColorBrush that did not register its name with a xref:System.Windows.FrameworkElement or xref:System.Windows.FrameworkContentElement, or was not used to set a property of a xref:System.Windows.FrameworkElement or xref:System.Windows.FrameworkContentElement.

How to Apply Animations with a Storyboard

To use a xref:System.Windows.Media.Animation.Storyboard to organize and apply animations, you add the animations as child timelines of the xref:System.Windows.Media.Animation.Storyboard. The xref:System.Windows.Media.Animation.Storyboard class provides the xref:System.Windows.Media.Animation.Storyboard.TargetName%2A?displayProperty=nameWithType and xref:System.Windows.Media.Animation.Storyboard.TargetProperty?displayProperty=nameWithType attached properties. You set these properties on an animation to specify its target object and property.

To apply animations to their targets, you begin the xref:System.Windows.Media.Animation.Storyboard using a trigger action or a method. In XAML, you use a xref:System.Windows.Media.Animation.BeginStoryboard object with an xref:System.Windows.EventTrigger, xref:System.Windows.Trigger, or xref:System.Windows.DataTrigger. In code, you can also use the xref:System.Windows.Media.Animation.Storyboard.Begin%2A method.

The following table shows the different places where each xref:System.Windows.Media.Animation.Storyboard begin technique is supported: per-instance, style, control template, and data template. "Per-Instance" refers to the technique of applying an animation or storyboard directly to instances of an object, rather than in a style, control template, or data template.

Storyboard is begun using… Per-instance Style Control template Data template Example
xref:System.Windows.Media.Animation.BeginStoryboard and an xref:System.Windows.EventTrigger Yes Yes Yes Yes Animate a Property by Using a Storyboard
xref:System.Windows.Media.Animation.BeginStoryboard and a property xref:System.Windows.Trigger No Yes Yes Yes Trigger an Animation When a Property Value Changes
xref:System.Windows.Media.Animation.BeginStoryboard and a property xref:System.Windows.MultiTrigger No Yes Yes Yes MultiTrigger class example
xref:System.Windows.Media.Animation.BeginStoryboard and a xref:System.Windows.DataTrigger No Yes Yes Yes How to: Trigger an Animation When Data Changes
xref:System.Windows.Media.Animation.BeginStoryboard and a xref:System.Windows.MultiDataTrigger No Yes Yes Yes MultiDataTrigger class example
xref:System.Windows.Media.Animation.Storyboard.Begin%2A method Yes No No No Animate a Property by Using a Storyboard

The following example uses a xref:System.Windows.Media.Animation.Storyboard to animate the xref:System.Windows.FrameworkElement.Width%2A of a xref:System.Windows.Shapes.Rectangle element and the xref:System.Windows.Media.SolidColorBrush.Color%2A of a xref:System.Windows.Media.SolidColorBrush used to paint that xref:System.Windows.Shapes.Rectangle.

[!code-xamlstoryboards_ovw_snip_XAML#1]

[!code-csharpstoryboards_ovw_snip#100]

The following sections describe the xref:System.Windows.Media.Animation.Storyboard.TargetName%2A and xref:System.Windows.Media.Animation.Storyboard.TargetProperty attached properties in more detail.

Targeting Framework Elements, Framework Content Elements, and Freezables

The previous section mentioned that, for an animation to find its target, it must know the target's name and the property to animate. Specifying the property to animate is straight forward: simply set TargetProperty with the name of the property to animate. You specify the name of the object whose property you want to animate by setting the xref:System.Windows.Media.Animation.Storyboard.TargetName%2A?displayProperty=nameWithType property on the animation.

Caution

While you can use the Target property to bind directly to an object as an alternative to TargetName, it isn't serializable. There is no guaranteed that the Target object can be correctly referenced in XAML.

For the xref:System.Windows.Setter.TargetName%2A property to work, the targeted object must have a name. Assigning a name to a xref:System.Windows.FrameworkElement or a xref:System.Windows.FrameworkContentElement in XAML is different than assigning a name to a xref:System.Windows.Freezable object.

Framework elements are those classes that inherit from the xref:System.Windows.FrameworkElement class. Examples of framework elements include xref:System.Windows.Window, xref:System.Windows.Controls.DockPanel, xref:System.Windows.Controls.Button, and xref:System.Windows.Shapes.Rectangle. Essentially all windows, panels, and controls are elements. Framework content elements are those classes that inherit from the xref:System.Windows.FrameworkContentElement class. Examples of framework content elements include xref:System.Windows.Documents.FlowDocument and xref:System.Windows.Documents.Paragraph. If you're not sure whether a type is a framework element or a framework content element, check to see whether it has a Name property. If it does, it's probably a framework element or a framework content element. To be sure, check the Inheritance Hierarchy section of its type page.

To enable the targeting of a framework element or a framework content element in XAML, you set its xref:System.Windows.FrameworkElement.Name%2A property. In code, you also need to use the xref:System.Windows.NameScope.RegisterName%2A method to register the element's name with the element for which you've created a xref:System.Windows.NameScope.

The following example, taken from the preceding example, assigns the name MyRectangle a xref:System.Windows.Shapes.Rectangle, a type of xref:System.Windows.FrameworkElement.

[!code-xamlstoryboards_ovw_snip_XAML#2]

[!code-csharpstoryboards_ovw_snip#102]

After it has a name, you can animate a property of that element.

[!code-xamlstoryboards_ovw_snip_XAML#5]

[!code-csharpstoryboards_ovw_snip#105]

xref:System.Windows.Freezable types are those classes that inherit from the xref:System.Windows.Freezable class. Examples of xref:System.Windows.Freezable include xref:System.Windows.Media.SolidColorBrush, xref:System.Windows.Media.RotateTransform, and xref:System.Windows.Media.GradientStop.

To enable the targeting of a xref:System.Windows.Freezable by an animation in XAML, you use the x:Name Directive to assign it a name. In code, you use the xref:System.Windows.NameScope.RegisterName%2A method to register its name with the element for which you've created a xref:System.Windows.NameScope.

The following example assigns a name to a xref:System.Windows.Freezable object.

[!code-xamlstoryboards_ovw_snip_XAML#3]

[!code-csharpstoryboards_ovw_snip#103]

The object can then be targeted by an animation.

[!code-xamlstoryboards_ovw_snip_XAML#7]

[!code-csharpstoryboards_ovw_snip#107]

xref:System.Windows.Media.Animation.Storyboard objects use name scopes to resolve the xref:System.Windows.Media.Animation.Storyboard.TargetName%2A property. For more information about WPF name scopes, see WPF XAML Namescopes. If the xref:System.Windows.Media.Animation.Storyboard.TargetName%2A property is omitted, the animation targets the element on which it is defined, or, in the case of styles, the styled element.

Sometimes a name can't be assigned to a xref:System.Windows.Freezable object. For example, if a xref:System.Windows.Freezable is declared as a resource or used to set a property value in a style, it can't be given a name. Because it doesn't have a name, it can't be targeted directly—but it can be targeted indirectly. The following sections describe how to use indirect targeting.

Indirect Targeting

There are times a xref:System.Windows.Freezable can't be targeted directly by an animation, such as when the xref:System.Windows.Freezable is declared as a resource or used to set a property value in a style. In these cases, even though you can't target it directly, you can still animate the xref:System.Windows.Freezable object. Instead of setting the xref:System.Windows.Media.Animation.Storyboard.TargetName%2A property with the name of the xref:System.Windows.Freezable, you give it the name of the element to which the xref:System.Windows.Freezable "belongs." For example, a xref:System.Windows.Media.SolidColorBrush used to set the xref:System.Windows.Shapes.Shape.Fill%2A of a rectangle element belongs to that rectangle. To animate the brush, you would set the animation's xref:System.Windows.Media.Animation.Storyboard.TargetProperty with a chain of properties that starts at the property of the framework element or framework content element the xref:System.Windows.Freezable was used to set and ends with the xref:System.Windows.Freezable property to animate.

[!code-xamlstoryboards_ovw_snip_XAML#33]

[!code-csharpstoryboards_ovw_snip#134]

Note that, if the xref:System.Windows.Freezable is frozen, a clone will be made, and that clone will be animated. When this happens, the original object's xref:System.Windows.Media.Animation.Animatable.HasAnimatedProperties%2A property continues to return false, because the original object is not actually animated. For more information about cloning, see the Freezable Objects Overview.

Also note that, when using indirect property targeting, it's possible to target objects that don't exist. For example, you might assume that the xref:System.Windows.Controls.Control.Background%2A of a particular button was set with a xref:System.Windows.Media.SolidColorBrush and try to animate its Color, when in fact a xref:System.Windows.Media.LinearGradientBrush was used to set the button's Background. In these cases, no exception is thrown; the animation fails to have a visible effect because xref:System.Windows.Media.LinearGradientBrush does not react to changes to the xref:System.Windows.Media.SolidColorBrush.Color%2A property.

The following sections describe indirect property targeting syntax in more detail.

Indirectly Targeting a Property of a Freezable in XAML

To target a property of a freezable in XAML, use the following syntax.

Property syntax
ElementPropertyName . FreezablePropertyName

Where

  • ElementPropertyName is the property of the xref:System.Windows.FrameworkElement which the xref:System.Windows.Freezable is used to set, and

  • FreezablePropertyName is the property of the xref:System.Windows.Freezable to animate.

The following code shows how to animate the xref:System.Windows.Media.SolidColorBrush.Color%2A of a xref:System.Windows.Media.SolidColorBrush used to set the xref:System.Windows.Shapes.Shape.Fill%2A of a rectangle element.

[!code-xamlstoryboards_ovw_snip_XAML#32]

Sometimes you need to target a freezable contained in a collection or array.

To target a freezable contained in a collection, you use the following path syntax.

Path syntax
ElementPropertyName .Children[ CollectionIndex ]. FreezablePropertyName

Where CollectionIndex is the index of the object in its array or collection.

For example, suppose that a rectangle has a xref:System.Windows.Media.TransformGroup resource applied to its xref:System.Windows.UIElement.RenderTransform%2A property, and you want to animate one of the transforms it contains.

[!code-xamlstoryboards_ovw_snip_XAML#34]

The following code shows how to animate the xref:System.Windows.Media.RotateTransform.Angle%2A property of the xref:System.Windows.Media.RotateTransform shown in the previous example.

[!code-xamlstoryboards_ovw_snip_XAML#35]

Indirectly Targeting a Property of a Freezable in Code

In code, you create a xref:System.Windows.PropertyPath object. When you create the xref:System.Windows.PropertyPath, you specify a xref:System.Windows.PropertyPath.Path%2A and xref:System.Windows.PropertyPath.PathParameters%2A.

To create xref:System.Windows.PropertyPath.PathParameters%2A, you create an array of type xref:System.Windows.DependencyProperty that contains a list of dependency property identifier fields. The first identifier field is for the property of the xref:System.Windows.FrameworkElement or xref:System.Windows.FrameworkContentElement that the xref:System.Windows.Freezable is used to set. The next identifier field represents the property of the xref:System.Windows.Freezable to target. Think of it as a chain of properties that connects the xref:System.Windows.Freezable to the xref:System.Windows.FrameworkElement object.

The following is an example of a dependency property chain that targets the xref:System.Windows.Media.SolidColorBrush.Color%2A of a xref:System.Windows.Media.SolidColorBrush used to set the xref:System.Windows.Shapes.Shape.Fill%2A of a rectangle element.

[!code-csharpstoryboards_ovw_snip#135]

You also need to specify a xref:System.Windows.PropertyPath.Path%2A. A xref:System.Windows.PropertyPath.Path%2A is a xref:System.String that tells the xref:System.Windows.PropertyPath.Path%2A how to interpret its xref:System.Windows.PropertyPath.PathParameters%2A. It uses the following syntax.

Property path syntax
( OwnerPropertyArrayIndex ).( FreezablePropertyArrayIndex )

Where

  • OwnerPropertyArrayIndex is the index of the xref:System.Windows.DependencyProperty array that contains the identifier of the xref:System.Windows.FrameworkElement object's property that the xref:System.Windows.Freezable is used to set, and

  • FreezablePropertyArrayIndex is the index of the xref:System.Windows.DependencyProperty array that contains the identifier of property to target.

The following example shows the xref:System.Windows.PropertyPath.Path%2A that would accompany the xref:System.Windows.PropertyPath.PathParameters%2A defined in the preceding example.

[!code-csharpstoryboards_ovw_snip#PropertyChainAndPath]

The following example combines the code in the previous examples to animate the xref:System.Windows.Media.SolidColorBrush.Color%2A of a xref:System.Windows.Media.SolidColorBrush used to set the xref:System.Windows.Shapes.Shape.Fill%2A of a rectangle element.

[!code-csharpstoryboards_ovw_snip#137]

Sometimes you need to target a freezable contained in a collection or array. For example, suppose that a rectangle has a xref:System.Windows.Media.TransformGroup resource applied to its xref:System.Windows.UIElement.RenderTransform%2A property, and you want to animate one of the transforms it contains.

[!code-xamlstoryboards_ovw_snip#142]

To target a xref:System.Windows.Freezable contained in a collection, you use the following path syntax.

Path syntax
( OwnerPropertyArrayIndex ).( CollectionChildrenPropertyArrayIndex ) [ CollectionIndex ].( FreezablePropertyArrayIndex )

Where CollectionIndex is the index of the object in its array or collection.

To target the xref:System.Windows.Media.RotateTransform.Angle%2A property of the xref:System.Windows.Media.RotateTransform, the second transform in the xref:System.Windows.Media.TransformGroup, you would use the following xref:System.Windows.PropertyPath.Path%2A and xref:System.Windows.PropertyPath.PathParameters%2A.

[!code-csharpstoryboards_ovw_snip#139]

The following example shows the complete code for animating the xref:System.Windows.Media.RotateTransform.Angle%2A of a xref:System.Windows.Media.RotateTransform contained within a xref:System.Windows.Media.TransformGroup.

[!code-csharpstoryboards_ovw_snip#138]

Indirectly Targeting with a Freezable as the Starting Point

The previous sections described how to indirectly target a xref:System.Windows.Freezable by starting with a xref:System.Windows.FrameworkElement or xref:System.Windows.FrameworkContentElement and creating a property chain to a xref:System.Windows.Freezable sub-property. You can also use a xref:System.Windows.Freezable as a starting point and indirectly target one of its xref:System.Windows.Freezable sub-properties. One additional restriction applies when using a xref:System.Windows.Freezable as a starting point for indirect targeting: the starting xref:System.Windows.Freezable and every xref:System.Windows.Freezable between it and the indirectly targeted sub-property must not be frozen.

Interactively Controlling a Storyboard in XAML

To start a storyboard in Extensible Application Markup Language (XAML), you use a xref:System.Windows.Media.Animation.BeginStoryboard trigger action. xref:System.Windows.Media.Animation.BeginStoryboard distributes the animations to the objects and properties they animate, and starts the storyboard. (For details about this process, see the Animation and Timing System Overview.) If you give the xref:System.Windows.Media.Animation.BeginStoryboard a name by specifying its xref:System.Windows.Media.Animation.BeginStoryboard.Name%2A property, you make it a controllable storyboard. You can then interactively control the storyboard after it's started. The following is a list of controllable storyboard actions that you use with event triggers to control a storyboard.

  • xref:System.Windows.Media.Animation.PauseStoryboard: Pauses the storyboard.

  • xref:System.Windows.Media.Animation.ResumeStoryboard: Resumes a paused storyboard.

  • xref:System.Windows.Media.Animation.SetStoryboardSpeedRatio: Changes the storyboard's speed.

  • xref:System.Windows.Media.Animation.SkipStoryboardToFill: Advances a storyboard to the end of its fill period, if it has one.

  • xref:System.Windows.Media.Animation.StopStoryboard: Stops the storyboard.

  • xref:System.Windows.Media.Animation.RemoveStoryboard: Removes the storyboard.

In the following example, controllable storyboard actions are used to interactively control a storyboard.

[!code-xamlanimation_ovws_snip#ControllableStoryboardExampleWholePage]

Interactively Controlling a Storyboard by Using Code

The previous examples have shown how to animate using trigger actions. In code, you may also control a storyboard using interactive methods of the xref:System.Windows.Media.Animation.Storyboard class. For a xref:System.Windows.Media.Animation.Storyboard to be made interactive in code, you must use the appropriate overload of the storyboard's xref:System.Windows.Media.Animation.Storyboard.Begin%2A method and specify true to make it controllable. See the xref:System.Windows.Media.Animation.Storyboard.Begin%28System.Windows.FrameworkElement%2CSystem.Boolean%29 page for more information.

The following list shows the methods that can be used to manipulate a xref:System.Windows.Media.Animation.Storyboard after it has started:

  • xref:System.Windows.Media.Animation.Storyboard.Pause%2A

  • xref:System.Windows.Media.Animation.Storyboard.Resume%2A

  • xref:System.Windows.Media.Animation.Storyboard.Seek%2A

  • xref:System.Windows.Media.Animation.Storyboard.SkipToFill%2A

  • xref:System.Windows.Media.Animation.Storyboard.Stop%2A

  • xref:System.Windows.Media.Animation.Storyboard.Remove%2A

The advantage to using these methods is that you don't need to create xref:System.Windows.Trigger or xref:System.Windows.TriggerAction objects; you just need a reference to the controllable xref:System.Windows.Media.Animation.Storyboard you want to manipulate.

Note

All interactive actions taken on a xref:System.Windows.Media.Animation.Clock, and therefore also on a xref:System.Windows.Media.Animation.Storyboard will occur on the next tick of the timing engine which will happen shortly before the next render. For example, if you use the xref:System.Windows.Media.Animation.Storyboard.Seek%2A method to jump to another point in an animation, the property value does not change instantly, rather, the value changes on the next tick of the timing engine.

The following example shows how to apply and control animations using the interactive methods of the xref:System.Windows.Media.Animation.Storyboard class.

[!code-csharpanimation_ovws_procedural_snip#ControllableStoryboardExampleWholePage] [!code-vbanimation_ovws_procedural_snip#ControllableStoryboardExampleWholePage]

Animate in a Style

You can use xref:System.Windows.Media.Animation.Storyboard objects to define animations in a xref:System.Windows.Style. Animating with a xref:System.Windows.Media.Animation.Storyboard in a xref:System.Windows.Style is similar to using a xref:System.Windows.Media.Animation.Storyboard elsewhere, with the following three exceptions:

  • You don't specify a xref:System.Windows.Media.Animation.Storyboard.TargetName%2A; the xref:System.Windows.Media.Animation.Storyboard always targets the element to which the xref:System.Windows.Style is applied. To target xref:System.Windows.Freezable objects, you must use indirect targeting. For more information about indirect targeting, see the Indirect Targeting section.

  • You can't specify a xref:System.Windows.EventTrigger.SourceName%2A for an xref:System.Windows.EventTrigger or a xref:System.Windows.Trigger.

  • You can't use dynamic resource references or data binding expressions to set xref:System.Windows.Media.Animation.Storyboard or animation property values. That's because everything inside a xref:System.Windows.Style must be thread-safe, and the timing system must xref:System.Windows.Freezable.Freeze%2Axref:System.Windows.Media.Animation.Storyboard objects to make them thread-safe. A xref:System.Windows.Media.Animation.Storyboard cannot be frozen if it or its child timelines contain dynamic resource references or data binding expressions. For more information about freezing and other xref:System.Windows.Freezable features, see the Freezable Objects Overview.

  • In XAML, you can't declare event handlers for xref:System.Windows.Media.Animation.Storyboard or animation events.

For an example showing how to define a storyboard in a style, see the Animate in a Style example.

Animate in a ControlTemplate

You can use xref:System.Windows.Media.Animation.Storyboard objects to define animations in a xref:System.Windows.Controls.ControlTemplate. Animating with a xref:System.Windows.Media.Animation.Storyboard in a xref:System.Windows.Controls.ControlTemplate is similar to using a xref:System.Windows.Media.Animation.Storyboard elsewhere, with the following two exceptions:

  • The xref:System.Windows.Media.Animation.Storyboard.TargetName%2A may only refer to child objects of the xref:System.Windows.Controls.ControlTemplate. If xref:System.Windows.Media.Animation.Storyboard.TargetName%2A is not specified, the animation targets the element to which the xref:System.Windows.Controls.ControlTemplate is applied.

  • The xref:System.Windows.EventTrigger.SourceName%2A for an xref:System.Windows.EventTrigger or a xref:System.Windows.Trigger may only refer to child objects of the xref:System.Windows.Controls.ControlTemplate.

  • You can't use dynamic resource references or data binding expressions to set xref:System.Windows.Media.Animation.Storyboard or animation property values. That's because everything inside a xref:System.Windows.Controls.ControlTemplate must be thread-safe, and the timing system must xref:System.Windows.Freezable.Freeze%2Axref:System.Windows.Media.Animation.Storyboard objects to make them thread-safe. A xref:System.Windows.Media.Animation.Storyboard cannot be frozen if it or its child timelines contain dynamic resource references or data binding expressions. For more information about freezing and other xref:System.Windows.Freezable features, see the Freezable Objects Overview.

  • In XAML, you can't declare event handlers for xref:System.Windows.Media.Animation.Storyboard or animation events.

For an example showing how to define a storyboard in a xref:System.Windows.Controls.ControlTemplate, see the Animate in a ControlTemplate example.

Animate When a Property Value Changes

In styles and control templates, you can use Trigger objects to start a storyboard when a property changes. For examples, see Trigger an Animation When a Property Value Changes and Animate in a ControlTemplate.

Animations applied by property xref:System.Windows.Trigger objects behave in a more complex fashion than xref:System.Windows.EventTrigger animations or animations started using xref:System.Windows.Media.Animation.Storyboard methods. They "handoff" with animations defined by other xref:System.Windows.Trigger objects, but compose with xref:System.Windows.EventTrigger and method-triggered animations.

See also