Procedura: animare una proprietà utilizzando uno storyboard

In questo esempio viene illustrato come usare un Storyboard oggetto per animare le proprietà. Per animare una proprietà usando un Storyboardoggetto , creare un'animazione per ogni proprietà che si desidera animare e creare un oggetto Storyboard per contenere le animazioni.

Il tipo di proprietà determina il tipo di animazione da usare. Ad esempio, per animare una proprietà che accetta Double valori, usare un oggetto DoubleAnimation. Le TargetName proprietà associate e TargetProperty specificano l'oggetto e la proprietà a cui viene applicata l'animazione.

Per avviare uno storyboard in Extensible Application Markup Language (XAML), usare un'azione BeginStoryboard e un oggetto EventTrigger. Inizia EventTrigger l'azione BeginStoryboard quando si verifica l'evento specificato dalla relativa RoutedEvent proprietà. L'azione BeginStoryboard avvia .Storyboard

Nell'esempio seguente vengono Storyboard utilizzati oggetti per animare due Button controlli. Per modificare le dimensioni del primo pulsante, viene Width animato. Per modificare il colore del secondo pulsante, la Color proprietà di SolidColorBrush viene utilizzata per impostare l'oggetto Background del pulsante animato.

Esempio

<!-- 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>

Nota

Anche se le animazioni possono essere destinate a entrambi gli FrameworkElement oggetti, ad esempio un Control oggetto o Panele un Freezable oggetto , ad esempio un Brush oggetto o Transform, solo gli elementi del framework dispongono di una Name proprietà . Per assegnare un nome a un oggetto freezable in modo che possa essere la destinazione di un'animazione, usare x:Name Directive, come illustrato nell'esempio precedente.

Se si usa il codice, è necessario creare un oggetto per un NameScopeFrameworkElement oggetto e registrare i nomi degli oggetti da animare con tale FrameworkElementoggetto . Per avviare le animazioni nel codice, usare un'azione BeginStoryboard con un oggetto EventTrigger. Facoltativamente, è possibile usare un gestore eventi e il Begin metodo di Storyboard. Nell'esempio seguente viene illustrato come utilizzare il metodo 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

Per altre informazioni sulle animazioni e storyboard, vedere Cenni preliminari sull'animazione.

Se si usa il codice, non ci si limita all'uso Storyboard di oggetti per animare le proprietà. Per altre informazioni ed esempi, vedere Animare una proprietà senza utilizzare uno Storyboard e Animare una proprietà utilizzando un oggetto AnimationClock.