Storyboards Overview
This topic shows how to use Storyboard objects to organize and apply animations. It describes how to interactively manipulate 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 TimelineGroup class, and include ParallelTimeline and Storyboard.
A Storyboard is a type of container timeline that provides targeting information for the timelines it contains. A Storyboard can contain any type of Timeline, including other container timelines and animations. 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. Storyboard objects enable you to organize animations and apply them in groups to one or more objects.
Where Can You Use a Storyboard?
A 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 NameScope of a FrameworkElement or a FrameworkContentElement.
For example, you could use a Storyboard to do the following:
Animate a SolidColorBrush (Non-framework element) that paints the Background of a Button (a type of FrameworkElement),
Animate a SolidColorBrush (Non-framework element) that paints the fill of a GeometryDrawing (Non-framework element) displayed using an Image (FrameworkElement).
In code, animate a SolidColorBrush declared by a class that also contains a FrameworkElement, if the SolidColorBrush registered its name with that FrameworkElement.
However, you could not use a Storyboard to animate a SolidColorBrush that did not register its name with a FrameworkElement or FrameworkContentElement, or was not used to set a property of a FrameworkElement or FrameworkContentElement.
How to Apply Animations with a Storyboard
To use a Storyboard to organize and apply animations, you add the animations as child timelines of the Storyboard. The Storyboard class provides the Storyboard.TargetName and Storyboard.TargetProperty 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 Storyboard using a trigger action or a method. In XAML, you use a BeginStoryboard object with an EventTrigger, Trigger, or DataTrigger. In code, you can also use the Begin method.
The following table shows the different places where each 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 |
|---|---|---|---|---|---|
BeginStoryboard and an EventTrigger |
Yes |
Yes |
Yes |
Yes |
|
BeginStoryboard and a property Trigger |
No |
Yes |
Yes |
Yes |
|
BeginStoryboard and a DataTrigger |
No |
Yes |
Yes |
Yes |
|
Begin method |
Yes |
No |
No |
No |
The following example uses a Storyboard to animate the Width of a Rectangle element and the Color of a SolidColorBrush used to paint that Rectangle.
<!-- This example shows how to animate with a storyboard.-->
<Page xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
x:Class="Microsoft.Samples.Animation.StoryboardsExample"
WindowTitle="Storyboards Example">
<StackPanel Margin="20">
<Rectangle Name="MyRectangle"
Width="100"
Height="100">
<Rectangle.Fill>
<SolidColorBrush x:Name="MySolidColorBrush" Color="Blue" />
</Rectangle.Fill>
<Rectangle.Triggers>
<EventTrigger RoutedEvent="Rectangle.MouseEnter">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation
Storyboard.TargetName="MyRectangle"
Storyboard.TargetProperty="Width"
From="100" To="200" Duration="0:0:1" />
<ColorAnimation
Storyboard.TargetName="MySolidColorBrush"
Storyboard.TargetProperty="Color"
From="Blue" To="Red" Duration="0:0:1" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Rectangle.Triggers>
</Rectangle>
</StackPanel>
</Page>
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Data;
using System.Windows.Shapes;
using System.Windows.Input;
namespace Microsoft.Samples.Animation
{
public class StoryboardsExample : Page
{
public StoryboardsExample()
{
this.WindowTitle = "Storyboards Example";
StackPanel myStackPanel = new StackPanel();
myStackPanel.Margin = new Thickness(20);
Rectangle myRectangle = new Rectangle();
myRectangle.Name = "MyRectangle";
// Create a name scope for the page.
NameScope.SetNameScope(this, new NameScope());
this.RegisterName(myRectangle.Name, myRectangle);
myRectangle.Width = 100;
myRectangle.Height = 100;
SolidColorBrush mySolidColorBrush = new SolidColorBrush(Colors.Blue);
this.RegisterName("MySolidColorBrush", mySolidColorBrush);
myRectangle.Fill = mySolidColorBrush;
DoubleAnimation myDoubleAnimation = new DoubleAnimation();
myDoubleAnimation.From = 100;
myDoubleAnimation.To = 200;
myDoubleAnimation.Duration = new Duration(TimeSpan.FromSeconds(1));
Storyboard.SetTargetName(myDoubleAnimation, myRectangle.Name);
Storyboard.SetTargetProperty(myDoubleAnimation,
new PropertyPath(Rectangle.WidthProperty));
ColorAnimation myColorAnimation = new ColorAnimation();
myColorAnimation.From = Colors.Blue;
myColorAnimation.To = Colors.Red;
myColorAnimation.Duration = new Duration(TimeSpan.FromSeconds(1));
Storyboard.SetTargetName(myColorAnimation, "MySolidColorBrush");
Storyboard.SetTargetProperty(myColorAnimation,
new PropertyPath(SolidColorBrush.ColorProperty));
Storyboard myStoryboard = new Storyboard();
myStoryboard.Children.Add(myDoubleAnimation);
myStoryboard.Children.Add(myColorAnimation);
myRectangle.MouseEnter += delegate(object sender, MouseEventArgs e)
{
myStoryboard.Begin(this);
};
myStackPanel.Children.Add(myRectangle);
this.Content = myStackPanel;
}
}
}
The following sections describe the TargetName and 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 Storyboard.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 Storyboard.TargetName property on the animation.
For the TargetName property to work, the targeted object must have a name. Assigning a name to a FrameworkElement or a FrameworkContentElement in XAML is different than assigning a name to a Freezable object.
Framework elements are those classes that inherit from the FrameworkElement class. Examples of framework elements include Window, DockPanel, Button, and Rectangle. Essentially all windows, panels, and controls are elements. Framework content elements are those classes that inherit from the FrameworkContentElement class. Examples of framework content elements include FlowDocument and 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 InheritanceHierarchy section of its type page.
To enable the targeting of a framework element or a framework content element in XAML, you set its Name property. In code, you also need to use the RegisterName method to register the element's name with the element for which you've created a NameScope.
The following example, taken from the preceding example, assigns the name MyRectangle a Rectangle, a type of FrameworkElement.
<Rectangle Name="MyRectangle"
Width="100"
Height="100">
Rectangle myRectangle = new Rectangle();
myRectangle.Name = "MyRectangle";
// Create a name scope for the page.
NameScope.SetNameScope(this, new NameScope());
this.RegisterName(myRectangle.Name, myRectangle);
After it has a name, you can animate a property of that element.
<DoubleAnimation
Storyboard.TargetName="MyRectangle"
Storyboard.TargetProperty="Width"
From="100" To="200" Duration="0:0:1" />
Storyboard.SetTargetName(myDoubleAnimation, myRectangle.Name);
Storyboard.SetTargetProperty(myDoubleAnimation,
new PropertyPath(Rectangle.WidthProperty));
Freezable types are those classes that inherit from the Freezable class. Examples of Freezable include SolidColorBrush, RotateTransform, and GradientStop.
To enable the targeting of a Freezable by an animation in XAML, you use the x:Name Attribute to assign it a name. In code, you use the RegisterName method to register its name with the element for which you've created a NameScope.
The following example assigns a name to a Freezable object.
<SolidColorBrush x:Name="MySolidColorBrush" Color="Blue" />
SolidColorBrush mySolidColorBrush = new SolidColorBrush(Colors.Blue);
this.RegisterName("MySolidColorBrush", mySolidColorBrush);
The object can then be targeted by an animation.
<ColorAnimation
Storyboard.TargetName="MySolidColorBrush"
Storyboard.TargetProperty="Color"
From="Blue" To="Red" Duration="0:0:1" />
Storyboard.SetTargetName(myColorAnimation, "MySolidColorBrush");
Storyboard.SetTargetProperty(myColorAnimation,
new PropertyPath(SolidColorBrush.ColorProperty));
Storyboard objects use name scopes to resolve the TargetName property. For more information about WPF name scopes, see WPF XAML Namescopes. If the TargetName 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 Freezable object. For example, if a 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 Freezable can't be targeted directly by an animation, such as when the 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 Freezable object. Instead of setting the TargetName property with the name of the Freezable, you give it the name of the element to which the Freezable "belongs." For example, a SolidColorBrush used to set the Fill of a rectangle element belongs to that rectangle. To animate the brush, you would set the animation's TargetProperty with a chain of properties that starts at the property of the framework element or framework content element the Freezable was used to set and ends with the Freezable property to animate.
<ColorAnimation
Storyboard.TargetName="Rectangle01"
Storyboard.TargetProperty="Fill.Color"
From="Blue" To="AliceBlue" Duration="0:0:1" />
DependencyProperty[] propertyChain =
new DependencyProperty[]
{Rectangle.FillProperty, SolidColorBrush.ColorProperty};
string thePath = "(0).(1)";
PropertyPath myPropertyPath = new PropertyPath(thePath, propertyChain);
Storyboard.SetTargetProperty(myColorAnimation, myPropertyPath);
Note that, if the Freezable is frozen, a clone will be made, and that clone will be animated. When this happens, the original object's HasAnimatedProperties 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 Background of a particular button was set with a SolidColorBrush and try to animate its Color, when in fact a 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 LinearGradientBrush does not react to changes to the Color 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.
ElementPropertyName.FreezablePropertyName |
Where
ElementPropertyName is the property of the FrameworkElement which the Freezable is used to set, and
FreezablePropertyName is the property of the Freezable to animate.
The following code shows how to animate the Color of a SolidColorBrush used to set the
Fill of a rectangle element.
<Rectangle
Name="Rectangle01"
Height="100"
Width="100"
Fill="{StaticResource MySolidColorBrushResource}">
<Rectangle.Triggers>
<EventTrigger RoutedEvent="Rectangle.MouseEnter">
<BeginStoryboard>
<Storyboard>
<ColorAnimation
Storyboard.TargetName="Rectangle01"
Storyboard.TargetProperty="Fill.Color"
From="Blue" To="AliceBlue" Duration="0:0:1" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Rectangle.Triggers>
</Rectangle>
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.
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 TransformGroup resource applied to its RenderTransform property, and you want to animate one of the transforms it contains.
<TransformGroup x:Key="MyTransformGroupResource"
x:Shared="False">
<ScaleTransform />
<RotateTransform />
</TransformGroup>
The following code shows how to animate the Angle property of the RotateTransform shown in the previous example.
<Rectangle
Name="Rectangle02"
Height="100"
Width="100"
Fill="Blue"
RenderTransform="{StaticResource MyTransformGroupResource}">
<Rectangle.Triggers>
<EventTrigger RoutedEvent="Rectangle.MouseEnter">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation
Storyboard.TargetName="Rectangle02"
Storyboard.TargetProperty="RenderTransform.Children[1].Angle"
From="0" To="360" Duration="0:0:1" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Rectangle.Triggers>
</Rectangle>
Indirectly Targeting a Property of a Freezable in Code
In code, you create a PropertyPath object. When you create the PropertyPath, you specify a Path and PathParameters.
To create PathParameters, you create an array of type DependencyProperty that contains a list of dependency property identifier fields. The first identifier field is for the property of the FrameworkElement or FrameworkContentElement that the Freezable is used to set. The next identifier field represents the property of the Freezable to target. Think of it as a chain of properties that connects the Freezable to the FrameworkElement object.
The following is an example of a dependency property chain that targets the Color of a SolidColorBrush used to set the Fill of a rectangle element.
DependencyProperty[] propertyChain =
new DependencyProperty[]
{Rectangle.FillProperty, SolidColorBrush.ColorProperty};
You also need to specify a Path. A Path is a String that tells the Path how to interpret its PathParameters. It uses the following syntax.
(OwnerPropertyArrayIndex).(FreezablePropertyArrayIndex) |
Where
OwnerPropertyArrayIndex is the index of the DependencyProperty array that contains the identifier of the FrameworkElement object's property that the Freezable is used to set, and
FreezablePropertyArrayIndex is the index of the DependencyProperty array that contains the identifier of property to target.
The following example shows the Path that would accompany the PathParameters defined in the preceding example.
DependencyProperty[] propertyChain =
new DependencyProperty[]
{Rectangle.FillProperty, SolidColorBrush.ColorProperty};
string thePath = "(0).(1)";
The following example combines the code in the previous examples to animate the Color of a SolidColorBrush used to set the Fill of a rectangle element.
// Create a name scope for the page.
NameScope.SetNameScope(this, new NameScope());
Rectangle rectangle01 = new Rectangle();
rectangle01.Name = "Rectangle01";
this.RegisterName(rectangle01.Name, rectangle01);
rectangle01.Width = 100;
rectangle01.Height = 100;
rectangle01.Fill =
(SolidColorBrush)this.Resources["MySolidColorBrushResource"];
ColorAnimation myColorAnimation = new ColorAnimation();
myColorAnimation.From = Colors.Blue;
myColorAnimation.To = Colors.AliceBlue;
myColorAnimation.Duration = new Duration(TimeSpan.FromSeconds(1));
Storyboard.SetTargetName(myColorAnimation, rectangle01.Name);
DependencyProperty[] propertyChain =
new DependencyProperty[]
{Rectangle.FillProperty, SolidColorBrush.ColorProperty};
string thePath = "(0).(1)";
PropertyPath myPropertyPath = new PropertyPath(thePath, propertyChain);
Storyboard.SetTargetProperty(myColorAnimation, myPropertyPath);
Storyboard myStoryboard = new Storyboard();
myStoryboard.Children.Add(myColorAnimation);
BeginStoryboard myBeginStoryboard = new BeginStoryboard();
myBeginStoryboard.Storyboard = myStoryboard;
EventTrigger myMouseEnterTrigger = new EventTrigger();
myMouseEnterTrigger.RoutedEvent = Rectangle.MouseEnterEvent;
myMouseEnterTrigger.Actions.Add(myBeginStoryboard);
rectangle01.Triggers.Add(myMouseEnterTrigger);
Sometimes you need to target a freezable contained in a collection or array. For example, suppose that a rectangle has a TransformGroup resource applied to its RenderTransform property, and you want to animate one of the transforms it contains.
<TransformGroup x:Key="MyTransformGroupResource"
x:Shared="False">
<ScaleTransform />
<RotateTransform />
</TransformGroup>
To target a Freezable contained in a collection, you use the following path syntax.
(OwnerPropertyArrayIndex).( CollectionChildrenPropertyArrayIndex) [CollectionIndex ].(FreezablePropertyArrayIndex) |
Where CollectionIndex is the index of the object in its array or collection.
To target the Angle property of the RotateTransform, the second transform in the TransformGroup, you would use the following Path and PathParameters.
DependencyProperty[] propertyChain =
new DependencyProperty[]
{
Rectangle.RenderTransformProperty,
TransformGroup.ChildrenProperty,
RotateTransform.AngleProperty
};
string thePath = "(0).(1)[1].(2)";
PropertyPath myPropertyPath = new PropertyPath(thePath, propertyChain);
Storyboard.SetTargetProperty(myDoubleAnimation, myPropertyPath);
The following example shows the complete code for animating the Angle of a RotateTransform contained within a TransformGroup.
Rectangle rectangle02 = new Rectangle();
rectangle02.Name = "Rectangle02";
this.RegisterName(rectangle02.Name, rectangle02);
rectangle02.Width = 100;
rectangle02.Height = 100;
rectangle02.Fill = Brushes.Blue;
rectangle02.RenderTransform =
(TransformGroup)this.Resources["MyTransformGroupResource"];
DoubleAnimation myDoubleAnimation = new DoubleAnimation();
myDoubleAnimation.From = 0;
myDoubleAnimation.To = 360;
myDoubleAnimation.Duration = new Duration(TimeSpan.FromSeconds(1));
Storyboard.SetTargetName(myDoubleAnimation, rectangle02.Name);
DependencyProperty[] propertyChain =
new DependencyProperty[]
{
Rectangle.RenderTransformProperty,
TransformGroup.ChildrenProperty,
RotateTransform.AngleProperty
};
string thePath = "(0).(1)[1].(2)";
PropertyPath myPropertyPath = new PropertyPath(thePath, propertyChain);
Storyboard.SetTargetProperty(myDoubleAnimation, myPropertyPath);
Storyboard myStoryboard = new Storyboard();
myStoryboard.Children.Add(myDoubleAnimation);
BeginStoryboard myBeginStoryboard = new BeginStoryboard();
myBeginStoryboard.Storyboard = myStoryboard;
EventTrigger myMouseEnterTrigger = new EventTrigger();
myMouseEnterTrigger.RoutedEvent = Rectangle.MouseEnterEvent;
myMouseEnterTrigger.Actions.Add(myBeginStoryboard);
rectangle02.Triggers.Add(myMouseEnterTrigger);
Indirectly Targeting with a Freezable as the Starting Point
The previous sections described how to indirectly target a Freezable by starting with a FrameworkElement or FrameworkContentElement and creating a property chain to a Freezable sub-property. You can also use a Freezable as a starting point and indirectly target one of its Freezable sub-properties. One additional restriction applies when using a Freezable as a starting point for indirect targeting: the starting Freezable and every 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 BeginStoryboard trigger action. 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 BeginStoryboard a name by specifying its Name 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.
PauseStoryboard: Pauses the storyboard.
ResumeStoryboard: Resumes a paused storyboard.
SetStoryboardSpeedRatio: Changes the storyboard's speed.
SkipStoryboardToFill: Advances a storyboard to the end of its fill period, if it has one.
StopStoryboard: Stops the storyboard.
RemoveStoryboard: Removes the storyboard.
In the following example, controllable storyboard actions are used to interactively control a storyboard.
<Page
xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
x:Class="Microsoft.SDK.Animation.ControllableStoryboardExample"
WindowTitle="Fading Rectangle Example">
<StackPanel Margin="10">
<Rectangle
Name="MyRectangle"
Width="100"
Height="100"
Fill="Blue">
</Rectangle>
<Button Name="BeginButton">Begin</Button>
<Button Name="PauseButton">Pause</Button>
<Button Name="ResumeButton">Resume</Button>
<Button Name="SkipToFillButton">Skip To Fill</Button>
<Button Name="StopButton">Stop</Button>
<StackPanel.Triggers>
<EventTrigger RoutedEvent="Button.Click" SourceName="BeginButton">
<BeginStoryboard Name="MyBeginStoryboard">
<Storyboard>
<DoubleAnimation
Storyboard.TargetName="MyRectangle"
Storyboard.TargetProperty="(Rectangle.Opacity)"
From="1.0" To="0.0" Duration="0:0:5" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<EventTrigger RoutedEvent="Button.Click" SourceName="PauseButton">
<PauseStoryboard BeginStoryboardName="MyBeginStoryboard" />
</EventTrigger>
<EventTrigger RoutedEvent="Button.Click" SourceName="ResumeButton">
<ResumeStoryboard BeginStoryboardName="MyBeginStoryboard" />
</EventTrigger>
<EventTrigger RoutedEvent="Button.Click" SourceName="SkipToFillButton">
<SkipStoryboardToFill BeginStoryboardName="MyBeginStoryboard" />
</EventTrigger>
<EventTrigger RoutedEvent="Button.Click" SourceName="StopButton">
<StopStoryboard BeginStoryboardName="MyBeginStoryboard" />
</EventTrigger>
</StackPanel.Triggers>
</StackPanel>
</Page>
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 Storyboard class. For a Storyboard to be made interactive in code, you must use the appropriate overload of the storyboard's Begin method and specify true to make it controllable. See the Begin(FrameworkElement, Boolean) page for more information.
The following list shows the methods that can be used to manipulate a Storyboard after it has started:
The advantage to using these methods is that you don't need to create Trigger or TriggerAction objects; you just need a reference to the controllable Storyboard you want to manipulate.
Note: All interactive actions taken on a Clock, and therefore also on a 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 Seek 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 Storyboard class.
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Shapes;
using System.Windows.Media;
using System.Windows.Media.Animation;
namespace SDKSample
{
public class ControllableStoryboardExample : Page
{
private Storyboard myStoryboard;
public ControllableStoryboardExample()
{
// Create a name scope for the page.
NameScope.SetNameScope(this, new NameScope());
this.WindowTitle = "Controllable Storyboard Example";
StackPanel myStackPanel = new StackPanel();
myStackPanel.Margin = new Thickness(10);
// Create a rectangle.
Rectangle myRectangle = new Rectangle();
myRectangle.Name = "myRectangle";
// Assign the rectangle a name by
// registering it with the page, so that
// it can be targeted by storyboard
// animations.
this.RegisterName(myRectangle.Name, myRectangle);
myRectangle.Width = 100;
myRectangle.Height = 100;
myRectangle.Fill = Brushes.Blue;
myStackPanel.Children.Add(myRectangle);
//
// Create an animation and a storyboard to animate the
// rectangle.
//
DoubleAnimation myDoubleAnimation = new DoubleAnimation();
myDoubleAnimation.From = 1.0;
myDoubleAnimation.To = 0.0;
myDoubleAnimation.Duration = new Duration(TimeSpan.FromMilliseconds(5000));
myDoubleAnimation.AutoReverse = true;
// Create the storyboard.
myStoryboard = new Storyboard();
myStoryboard.Children.Add(myDoubleAnimation);
Storyboard.SetTargetName(myDoubleAnimation, myRectangle.Name);
Storyboard.SetTargetProperty(myDoubleAnimation, new PropertyPath(Rectangle.OpacityProperty));
//
// Create some buttons to control the storyboard
// and a panel to contain them.
//
StackPanel buttonPanel = new StackPanel();
buttonPanel.Orientation = Orientation.Horizontal;
Button beginButton = new Button();
beginButton.Content = "Begin";
beginButton.Click += new RoutedEventHandler(beginButton_Clicked);
buttonPanel.Children.Add(beginButton);
Button pauseButton = new Button();
pauseButton.Content = "Pause";
pauseButton.Click += new RoutedEventHandler(pauseButton_Clicked);
buttonPanel.Children.Add(pauseButton);
Button resumeButton = new Button();
resumeButton.Content = "Resume";
resumeButton.Click += new RoutedEventHandler(resumeButton_Clicked);
buttonPanel.Children.Add(resumeButton);
Button skipToFillButton = new Button();
skipToFillButton.Content = "Skip to Fill";
skipToFillButton.Click += new RoutedEventHandler(skipToFillButton_Clicked);
buttonPanel.Children.Add(skipToFillButton);
Button setSpeedRatioButton = new Button();
setSpeedRatioButton.Content = "Triple Speed";
setSpeedRatioButton.Click += new RoutedEventHandler(setSpeedRatioButton_Clicked);
buttonPanel.Children.Add(setSpeedRatioButton);
Button stopButton = new Button();
stopButton.Content = "Stop";
stopButton.Click += new RoutedEventHandler(stopButton_Clicked);
buttonPanel.Children.Add(stopButton);
myStackPanel.Children.Add(buttonPanel);
this.Content = myStackPanel;
}
// Begins the storyboard.
private void beginButton_Clicked(object sender, RoutedEventArgs args)
{
// Specifying "true" as the second Begin parameter
// makes this storyboard controllable.
myStoryboard.Begin(this, true);
}
// Pauses the storyboard.
private void pauseButton_Clicked(object sender, RoutedEventArgs args)
{
myStoryboard.Pause(this);
}
// Resumes the storyboard.
private void resumeButton_Clicked(object sender, RoutedEventArgs args)
{
myStoryboard.Resume(this);
}
// Advances the storyboard to its fill period.
private void skipToFillButton_Clicked(object sender, RoutedEventArgs args)
{
myStoryboard.SkipToFill(this);
}
// Updates the storyboard's speed.
private void setSpeedRatioButton_Clicked(object sender, RoutedEventArgs args)
{
// Makes the storyboard progress three times as fast as normal.
myStoryboard.SetSpeedRatio(this, 3);
}
// Stops the storyboard.
private void stopButton_Clicked(object sender, RoutedEventArgs args)
{
myStoryboard.Stop(this);
}
}
}
Animate in a Style
You can use Storyboard objects to define animations in a Style. Animating with a Storyboard in a Style is similar to using a Storyboard elsewhere, with the following three exceptions:
You don't specify a TargetName; the Storyboard always targets the element to which the Style is applied. To target Freezable objects, you must use indirect targeting. For more information about indirect targeting, see the Indirect Targeting section.
You can't specify a SourceName for an EventTrigger or a Trigger.
You can't use dynamic resource references or data binding expressions to set Storyboard or animation property values. That's because everything inside a Style must be thread-safe, and the timing system must Freeze Storyboard objects to make them thread-safe. A 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 Freezable features, see the Freezable Objects Overview.
In XAML, you can't declare event handlers for Storyboard or animation events.
For an example showing how to define a storyboard in a style, see the How to: Animate in a Style example.
Animate in a ControlTemplate
You can use Storyboard objects to define animations in a ControlTemplate. Animating with a Storyboard in a ControlTemplate is similar to using a Storyboard elsewhere, with the following two exceptions:
The TargetName may only refer to child objects of the ControlTemplate. If TargetName is not specified, the animation targets the element to which the ControlTemplate is applied.
The SourceName for an EventTrigger or a Trigger may only refer to child objects of the ControlTemplate.
You can't use dynamic resource references or data binding expressions to set Storyboard or animation property values. That's because everything inside a ControlTemplate must be thread-safe, and the timing system must Freeze Storyboard objects to make them thread-safe. A 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 Freezable features, see the Freezable Objects Overview.
In XAML, you can't declare event handlers for Storyboard or animation events.
For an example showing how to define a storyboard in a ControlTemplate, see the How to: 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 How to: Trigger an Animation When a Property Value Changes and How to: Animate in a ControlTemplate.
Animations applied by property Trigger objects behave in a more complex fashion than EventTrigger animations or animations started using Storyboard methods. They "handoff" with animations defined by other Trigger objects, but compose with EventTrigger and method-triggered animations.