Guide pratique pour animer une propriété à l’aide d’un storyboard

Cet exemple montre comment utiliser un Storyboard pour animer des propriétés. Pour animer une propriété à l’aide d’un Storyboard, créez une animation pour chaque propriété que vous souhaitez animer et créez également un Storyboard pour contenir les animations.

Le type de propriété détermine le type d’animation à utiliser. Par exemple, pour animer une propriété qui prend des valeurs Double, utilisez une DoubleAnimation. Les propriétés jointes TargetName et TargetProperty spécifient l’objet et la propriété auxquels l’animation est appliquée.

Pour démarrer un storyboard en XAML (Extensible Application Markup Language), utilisez une action de BeginStoryboard et un EventTrigger. La EventTrigger commence l’action de BeginStoryboard lorsque l’événement spécifié par sa propriété RoutedEvent se produit. L’action BeginStoryboard démarre le Storyboard.

L’exemple suivant utilise Storyboard objets pour animer deux contrôles Button. Pour modifier la taille du premier bouton, sa Width est animée. Pour modifier la couleur du deuxième bouton, la propriété Color du SolidColorBrush est utilisée pour définir la Background du bouton animé.

Exemple :

<!-- 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>

Remarque

Bien que les animations puissent cibler à la fois un objet FrameworkElement, tel qu’un Control ou un Panel, et un objet Freezable, tel qu’un Brush ou un Transform, seuls les éléments de framework ont une propriété Name. Pour affecter un nom à un freezable afin qu’il puisse être ciblé par une animation, utilisez la directive x :Name, comme l’illustre l’exemple précédent.

Si vous utilisez du code, vous devez créer un NameScope pour un FrameworkElement et inscrire les noms des objets à animer avec ce FrameworkElement. Pour démarrer les animations dans le code, utilisez une action BeginStoryboard avec un EventTrigger. Si vous le souhaitez, vous pouvez utiliser un gestionnaire d’événements et la méthode Begin de Storyboard. L’exemple suivant montre comment utiliser la méthode Begin.

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;
        }
    }
}

Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Media.Animation

Namespace SDKSample


    ' Uses a storyboard to animate the properties
    ' of two buttons.
    Public Class StoryboardExample
        Inherits Page
        
        Private Dim WithEvents myWidthAnimatedButton As Button
        Private Dim WithEvents myColorAnimatedButton As Button        
        Private Dim myWidthAnimatedButtonStoryboard As Storyboard
        Private Dim myColorAnimatedButtonStoryboard As Storyboard
        

        Public Sub New()
            ' Create a name scope for the page.
            NameScope.SetNameScope(Me, New NameScope())

            Me.WindowTitle = "Animate Properties using Storyboards"
            Dim myStackPanel As New StackPanel()
            myStackPanel.MinWidth = 500
            myStackPanel.Margin = New Thickness(30)
            myStackPanel.HorizontalAlignment = HorizontalAlignment.Left
            Dim myTextBlock As New TextBlock()
            myTextBlock.Text = "Storyboard Animation Example"
            myStackPanel.Children.Add(myTextBlock)

            '
            ' Create and animate the first button.
            '

            ' Create a 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.
            Me.RegisterName(myWidthAnimatedButton.Name, myWidthAnimatedButton)

            ' Create a DoubleAnimation to animate the width of the button.
            Dim myDoubleAnimation As 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.
            myWidthAnimatedButtonStoryboard = New Storyboard()
            myWidthAnimatedButtonStoryboard.Children.Add(myDoubleAnimation)

            myStackPanel.Children.Add(myWidthAnimatedButton)

            '
            ' Create and animate the second button.
            '

            ' Create a second 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.
            Dim myBackgroundBrush As 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.
            Me.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.
            Dim myColorAnimation As 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.
            myColorAnimatedButtonStoryboard = New Storyboard()
            myColorAnimatedButtonStoryboard.Children.Add(myColorAnimation)

            myStackPanel.Children.Add(myColorAnimatedButton)
            Me.Content = myStackPanel

        End Sub
        
        ' Start the animation when the button is clicked.
        Private Sub myWidthAnimatedButton_Loaded(ByVal sender as object, ByVal args as RoutedEventArgs) Handles myWidthAnimatedButton.Click
        
            myWidthAnimatedButtonStoryboard.Begin(myWidthAnimatedButton)
        
        End Sub        
        
        ' Start the animation when the button is clicked.
        Private Sub myColorAnimatedButton_Loaded(ByVal sender as object, ByVal args as RoutedEventArgs) Handles myColorAnimatedButton.Click
        
            myColorAnimatedButtonStoryboard.Begin(myColorAnimatedButton)
        
        End Sub           
        
    End Class
End Namespace

Pour plus d’informations sur les animations et les storyboards, consultez Vue d’ensemble de l’animation.

Si vous utilisez du code, vous n’êtes pas limité à l’utilisation d’objets Storyboard afin d’animer les propriétés. Pour plus d’informations et d’exemples, consultez Animer une propriété sans utiliser de storyboard et Animer une propriété à l’aide d’un AnimationClock.