Como controlar um storyboard depois de ter começado

Este exemplo mostra como usar o código para controlar um Storyboard depois que ele é iniciado. Para controlar um storyboard em XAML, use Trigger e TriggerAction objetos, por exemplo, consulte Usar gatilhos de eventos para controlar um storyboard depois que ele é iniciado.

Para iniciar um storyboard, use seu Begin método, que distribui as animações do storyboard para as propriedades que eles animam e inicia o storyboard.

Para tornar um storyboard controlável, use o método e especifique true como o Begin segundo parâmetro. Em seguida, use os métodos interativos do storyboard para pausar, retomar, procurar, parar, acelerar ou retardar o storyboard ou avançar para seu período de preenchimento. A seguir temos uma lista de métodos interativos de storyboard:

  • Pause: Pausa o storyboard.

  • Resume: Retoma um storyboard pausado.

  • SetSpeedRatio: Define a velocidade interativa do storyboard.

  • Seek: Procura o storyboard no local especificado.

  • SeekAlignedToLastTick: Busca o storyboard para o local especificado. Ao contrário do método, esta operação é processada antes do Seek próximo tick.

  • SkipToFill: Avança o storyboard para o seu período de preenchimento, se tiver um.

  • Stop: Interrompe o storyboard.

No exemplo a seguir, diversos métodos de storyboard são usados para controlar de forma interativa um storyboard.

Observação

Para ver um exemplo de controle de um storyboard usando gatilhos com XAML, consulte Usar gatilhos de eventos para controlar um storyboard depois que ele é iniciado.

Exemplo

/*
    This example shows how to control
    a storyboard after it has started.

*/

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

namespace Microsoft.Samples.Animation.TimingBehaviors
{
    public partial class ControlStoryboardExample : Page
    {

        private Storyboard myStoryboard;

        public ControlStoryboardExample()
        {

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

            this.WindowTitle = "Controlling a Storyboard";
            this.Background = Brushes.White;

            StackPanel myStackPanel = new StackPanel();
            myStackPanel.Margin = new Thickness(20);

            // Create a rectangle.
            Rectangle myRectangle = new Rectangle();
            myRectangle.Width = 100;
            myRectangle.Height = 20;
            myRectangle.Margin = new Thickness(12,0,0,5);
            myRectangle.Fill = new SolidColorBrush(Color.FromArgb(170, 51, 51, 255));
            myRectangle.HorizontalAlignment = HorizontalAlignment.Left;
            myStackPanel.Children.Add(myRectangle);

            // Assign the rectangle a name by
            // registering it with the page, so that
            // it can be targeted by storyboard
            // animations.
            this.RegisterName("myRectangle", myRectangle);

            //
            // Create an animation and a storyboard to animate the
            // rectangle.
            //
            DoubleAnimation myDoubleAnimation =
                new DoubleAnimation(100, 500, new Duration(TimeSpan.FromSeconds(5)));
            Storyboard.SetTargetName(myDoubleAnimation, "myRectangle");
            Storyboard.SetTargetProperty(myDoubleAnimation, new PropertyPath(Rectangle.WidthProperty));
            myStoryboard = new Storyboard();
            myStoryboard.Children.Add(myDoubleAnimation);

            //
            // 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);
        }
    }
}
'
'    This example shows how to control
'    a storyboard after it has started.
'
'


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


Namespace Microsoft.Samples.Animation.TimingBehaviors
    Partial Public Class ControlStoryboardExample
        Inherits Page

        Private ReadOnly myStoryboard As Storyboard

        Public Sub New()

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

            WindowTitle = "Controlling a Storyboard"
            Background = Brushes.White

            Dim myStackPanel As New StackPanel With {
                .Margin = New Thickness(20)
            }

                ' Create a rectangle.
            Dim myRectangle As New Rectangle With {
                .Width = 100,
                .Height = 20,
                .Margin = New Thickness(12, 0, 0, 5),
                .Fill = New SolidColorBrush(Color.FromArgb(170, 51, 51, 255)),
                .HorizontalAlignment = HorizontalAlignment.Left
            }
            myStackPanel.Children.Add(myRectangle)

            ' Assign the rectangle a name by 
            ' registering it with the page, so that
            ' it can be targeted by storyboard
            ' animations.
            RegisterName("myRectangle", myRectangle)

            '
            ' Create an animation and a storyboard to animate the
            ' rectangle.
            '
            Dim myDoubleAnimation As New DoubleAnimation(100, 500, New Duration(TimeSpan.FromSeconds(5)))
            Storyboard.SetTargetName(myDoubleAnimation, "myRectangle")
            Storyboard.SetTargetProperty(myDoubleAnimation, New PropertyPath(Rectangle.WidthProperty))
            myStoryboard = New Storyboard()
            myStoryboard.Children.Add(myDoubleAnimation)

            '
            ' Create some buttons to control the storyboard
            ' and a panel to contain them.
            '
            Dim buttonPanel As New StackPanel With {
                .Orientation = Orientation.Horizontal
            }
            Dim beginButton As New Button With {
                .Content = "Begin"
            }
            AddHandler beginButton.Click, AddressOf beginButton_Clicked
            buttonPanel.Children.Add(beginButton)
            Dim pauseButton As New Button With {
                .Content = "Pause"
            }
            AddHandler pauseButton.Click, AddressOf pauseButton_Clicked
            buttonPanel.Children.Add(pauseButton)
            Dim resumeButton As New Button With {
                .Content = "Resume"
            }
            AddHandler resumeButton.Click, AddressOf resumeButton_Clicked
            buttonPanel.Children.Add(resumeButton)
            Dim skipToFillButton As New Button With {
                .Content = "Skip to Fill"
            }
            AddHandler skipToFillButton.Click, AddressOf skipToFillButton_Clicked
            buttonPanel.Children.Add(skipToFillButton)
            Dim setSpeedRatioButton As New Button With {
                .Content = "Triple Speed"
            }
            AddHandler setSpeedRatioButton.Click, AddressOf setSpeedRatioButton_Clicked
            buttonPanel.Children.Add(setSpeedRatioButton)
            Dim stopButton As New Button With {
                .Content = "Stop"
            }
            AddHandler stopButton.Click, AddressOf stopButton_Clicked
            buttonPanel.Children.Add(stopButton)
            myStackPanel.Children.Add(buttonPanel)
            Content = myStackPanel
        End Sub

        ' Begins the storyboard.
        Private Sub beginButton_Clicked(sender As Object, args As RoutedEventArgs)
            ' Specifying "true" as the second Begin parameter
            ' makes this storyboard controllable.
            myStoryboard.Begin(Me, True)

        End Sub

        ' Pauses the storyboard.
        Private Sub pauseButton_Clicked(sender As Object, args As RoutedEventArgs)
            myStoryboard.Pause(Me)

        End Sub

        ' Resumes the storyboard.
        Private Sub resumeButton_Clicked(sender As Object, args As RoutedEventArgs)
            myStoryboard.Resume(Me)

        End Sub

        ' Advances the storyboard to its fill period.
        Private Sub skipToFillButton_Clicked(sender As Object, args As RoutedEventArgs)
            myStoryboard.SkipToFill(Me)

        End Sub

        ' Updates the storyboard's speed.
        Private Sub setSpeedRatioButton_Clicked(sender As Object, args As RoutedEventArgs)
            ' Makes the storyboard progress three times as fast as normal.
            myStoryboard.SetSpeedRatio(Me, 3)

        End Sub

        ' Stops the storyboard.
        Private Sub stopButton_Clicked(sender As Object, args As RoutedEventArgs)
            myStoryboard.Stop(Me)

        End Sub



    End Class
End Namespace

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