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BeginStoryboard Class

A trigger action that begins a Storyboard and distributes its animations to their targeted objects and properties.

Namespace:  System.Windows.Media.Animation
Assembly:  PresentationFramework (in PresentationFramework.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
[RuntimeNamePropertyAttribute("Name")]
[ContentPropertyAttribute("Storyboard")]
public sealed class BeginStoryboard : TriggerAction
<BeginStoryboard>
  Storyboard
</BeginStoryboard>

Use a BeginStoryboard action with an EventTrigger or a Trigger to apply animations to their target properties and start them. BeginStoryboard begins a Storyboard by calling Begin on its Storyboard reference when triggered.

When you begin a Storyboard on a property that is already being animated by another Storyboard, the HandoffBehavior property of BeginStoryboard determines how the animation proceeds.

Pause, Resume, Stop, or Otherwise Control a Storyboard Interactively

To be able to pause, resume, or otherwise control a Storyboard that was declared in markup interactively, you must set the Name property of its BeginStoryboard. You can then control the Storyboard by using a ControllableStoryboardAction object (such as PauseStoryboard, ResumeStoryboard, or StopStoryboard) to control it by referencing its Name. If the Name of BeginStoryboard is unspecified, the Storyboard cannot be interactively controlled after it is begun. See How to: Use Event Triggers to Control a Storyboard After It Starts for more information.

NoteNote:

In code, you may use the interactive methods of the Storyboard class to control a Storyboard that was applied using a BeginStoryboard. As is the case when using ControllableStoryboardAction objects, you must give the BeginStoryboard a name for its Storyboard to be interactively controllable.

This example shows how to use a Storyboard to animate properties. To animate a property by using a Storyboard, create an animation for each property that you want to animate and also create a Storyboard to contain the animations.

The type of property determines the type of animation to use. For example, to animate a property that takes Double values, use a DoubleAnimation. The TargetName and TargetProperty attached properties specify the object and property to which the animation is applied.

To start a storyboard in Extensible Application Markup Language (XAML), use a BeginStoryboard action and an EventTrigger. The EventTrigger begins the BeginStoryboard action when the event that is specified by its RoutedEvent property occurs. The BeginStoryboard action starts the Storyboard.

The following example uses Storyboard objects to animate two Button controls. To make the first button change in size, its Width is animated. To make the second button change color, the Color property of the SolidColorBrush is used to set the Background of the button that is animated.

<!-- StoryboardExample.xaml
     Uses storyboards to animate properties. -->
<Page
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  WindowTitle="Animate Properties with Storyboards">

  <Border Background="White">
    <StackPanel Margin="30" HorizontalAlignment="Left" MinWidth="500">

      <TextBlock>Storyboard Animation Example</TextBlock>

      <!-- The width of this button is animated. -->
      <Button Name="myWidthAnimatedButton"
        Height="30" Width="200" HorizontalAlignment="Left">
        A Button   
        <Button.Triggers>

          <!-- Animates the width of the first button 
               from 200 to 300. -->         
          <EventTrigger RoutedEvent="Button.Click">
            <BeginStoryboard>
              <Storyboard>           
                <DoubleAnimation Storyboard.TargetName="myWidthAnimatedButton"
                  Storyboard.TargetProperty="Width"
                  From="200" To="300" Duration="0:0:3" />
              </Storyboard>
            </BeginStoryboard>
          </EventTrigger>
        </Button.Triggers>
      </Button>

      <!-- The color of the brush used to paint this button is animated. -->
      <Button Height="30" Width="200" 
        HorizontalAlignment="Left">Another Button
        <Button.Background>
          <SolidColorBrush x:Name="myAnimatedBrush" Color="Blue" />
        </Button.Background>
        <Button.Triggers>

        <!-- Animates the color of the brush used to paint 
             the second button from red to blue . -->             
          <EventTrigger RoutedEvent="Button.Click">    
            <BeginStoryboard>
              <Storyboard>
                <ColorAnimation 
                  Storyboard.TargetName="myAnimatedBrush"
                  Storyboard.TargetProperty="Color"
                  From="Red" To="Blue" Duration="0:0:7" />
              </Storyboard>
            </BeginStoryboard>
          </EventTrigger>
        </Button.Triggers>
      </Button>
    </StackPanel>
  </Border>
</Page>
NoteNote:

Although animations can target both a FrameworkElement object, such as a Control or Panel, and a Freezable object, such as a Brush or Transform, only framework elements have a Name property. To assign a name to a freezable so that it can be targeted by an animation, use the x:Name Attribute, as the previous example shows.

If you use code, you must create a NameScope for a FrameworkElement and register the names of the objects to animate with that FrameworkElement. To start the animations in code, use a BeginStoryboard action with an EventTrigger. Optionally, you can use an event handler and the Begin method of Storyboard. The following example shows how to use the Begin method.

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;

namespace Microsoft.Samples.Animation.AnimatingWithStoryboards
{


    // Uses a storyboard to animate the properties 
    // of two buttons. 
    public class StoryboardExample : Page
    {

        public StoryboardExample()
        {
            // Create a name scope for the page.
            NameScope.SetNameScope(this, new NameScope());

            this.WindowTitle = "Animate Properties using Storyboards";
            StackPanel myStackPanel = new StackPanel();
            myStackPanel.MinWidth = 500;
            myStackPanel.Margin = new Thickness(30);
            myStackPanel.HorizontalAlignment = HorizontalAlignment.Left;
            TextBlock myTextBlock = new TextBlock();
            myTextBlock.Text = "Storyboard Animation Example";
            myStackPanel.Children.Add(myTextBlock);

            // 
            // Create and animate the first button. 
            // 

            // Create a button.
            Button myWidthAnimatedButton = new Button();
            myWidthAnimatedButton.Height = 30;
            myWidthAnimatedButton.Width = 200;
            myWidthAnimatedButton.HorizontalAlignment = HorizontalAlignment.Left;
            myWidthAnimatedButton.Content = "A Button";

            // Set the Name of the button so that it can be referred 
            // to in the storyboard that's created later. 
            // The ID doesn't have to match the variable name; 
            // it can be any unique identifier.
            myWidthAnimatedButton.Name = "myWidthAnimatedButton";

            // Register the name with the page to which the button belongs. 
            this.RegisterName(myWidthAnimatedButton.Name, myWidthAnimatedButton);

            // Create a DoubleAnimation to animate the width of the button.
            DoubleAnimation myDoubleAnimation = new DoubleAnimation();
            myDoubleAnimation.From = 200;
            myDoubleAnimation.To = 300;
            myDoubleAnimation.Duration = new Duration(TimeSpan.FromMilliseconds(3000));          

            // Configure the animation to target the button's Width property.
            Storyboard.SetTargetName(myDoubleAnimation, myWidthAnimatedButton.Name); 
            Storyboard.SetTargetProperty(myDoubleAnimation, new PropertyPath(Button.WidthProperty));

            // Create a storyboard to contain the animation.
            Storyboard myWidthAnimatedButtonStoryboard = new Storyboard();
            myWidthAnimatedButtonStoryboard.Children.Add(myDoubleAnimation);

            // Animate the button width when it's clicked.
            myWidthAnimatedButton.Click += delegate(object sender, RoutedEventArgs args)
                {
                    myWidthAnimatedButtonStoryboard.Begin(myWidthAnimatedButton);
                };


            myStackPanel.Children.Add(myWidthAnimatedButton);

            // 
            // Create and animate the second button. 
            // 

            // Create a second button.
            Button myColorAnimatedButton = new Button();
            myColorAnimatedButton.Height = 30;
            myColorAnimatedButton.Width = 200;
            myColorAnimatedButton.HorizontalAlignment = HorizontalAlignment.Left;
            myColorAnimatedButton.Content = "Another Button";

            // Create a SolidColorBrush to paint the button's background.
            SolidColorBrush myBackgroundBrush = new SolidColorBrush();
            myBackgroundBrush.Color = Colors.Blue;

            // Because a Brush isn't a FrameworkElement, it doesn't 
            // have a Name property to set. Instead, you just 
            // register a name for the SolidColorBrush with 
            // the page where it's used. 
            this.RegisterName("myAnimatedBrush", myBackgroundBrush);

            // Use the brush to paint the background of the button.
            myColorAnimatedButton.Background = myBackgroundBrush;

            // Create a ColorAnimation to animate the button's background.
            ColorAnimation myColorAnimation = new ColorAnimation();
            myColorAnimation.From = Colors.Red;
            myColorAnimation.To = Colors.Blue;
            myColorAnimation.Duration = new Duration(TimeSpan.FromMilliseconds(7000));    

            // Configure the animation to target the brush's Color property.
            Storyboard.SetTargetName(myColorAnimation, "myAnimatedBrush");                        
            Storyboard.SetTargetProperty(myColorAnimation, new PropertyPath(SolidColorBrush.ColorProperty));    

            // Create a storyboard to contain the animation.
            Storyboard myColorAnimatedButtonStoryboard = new Storyboard();
            myColorAnimatedButtonStoryboard.Children.Add(myColorAnimation);

            // Animate the button background color when it's clicked.
            myColorAnimatedButton.Click += delegate(object sender, RoutedEventArgs args)
                {
                    myColorAnimatedButtonStoryboard.Begin(myColorAnimatedButton);
                };


            myStackPanel.Children.Add(myColorAnimatedButton);
            this.Content = myStackPanel;

        }
    }
}

For the complete sample, see Property Animation Sample. For more information about animation and storyboards, see Animation Overview.

If you use code, you are not limited to using Storyboard objects in order to animate properties. For more information and examples, see How to: Animate a Property Without Using a Storyboard and How to: Animate a Property by Using an AnimationClock.

More Code

How to: Trigger an Animation When a Property Value Changes This example shows how to use a Trigger to start a Storyboard when a property value changes. You can use a Trigger inside a Style, ControlTemplate, or DataTemplate.
How to: Specify HandoffBehavior Between Storyboard Animations This example shows how to specify handoff behavior between storyboard animations. The HandoffBehavior property of BeginStoryboard specifies how new animations interact with any existing ones that are already applied to a property.
How to: Animate in a Style This example shows how to animate properties within a style. When animating within a style, only the framework element for which the style is defined can be targeted directly. To target a freezable object, you must "dot down" from a property of the styled element.
How to: Use Event Triggers to Control a Storyboard After It Starts This example shows how to control a Storyboard after it starts. To start a Storyboard by using XAML, use BeginStoryboard, which distributes the animations to the objects and properties they animate and then starts the storyboard. If you give BeginStoryboard a name by specifying its Name property, you make it a controllable storyboard. You can then interactively control the storyboard after it starts.
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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.

.NET Framework

Supported in: 3.5, 3.0

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