Procedura: cercare uno storyboard in modo sincrono

Aggiornamento: novembre 2007

Nell'esempio riportato di seguito viene illustrato come utilizzare il metodo SeekAlignedToLastTick di Storyboard per cercare in modo sincrono qualsiasi posizione dell'animazione di uno storyboard.

Esempio

Di seguito viene riportato il markup XAML per l'esempio.

<Page xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation" 
  xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="SDKSample.SeekStoryboardSynchronouslyExample">
  <StackPanel Margin="20" >

    <Rectangle Name="myRectangle"
      Width="10" Height="20" Fill="#AA3333FF" HorizontalAlignment="Left" >
      <Rectangle.Triggers>
        <EventTrigger RoutedEvent="Rectangle.Loaded">
          <BeginStoryboard Name="myBeginStoryboard">
            <Storyboard Name="myStoryboard" Duration="0:0:4">
              <DoubleAnimation 
                Storyboard.TargetName="myRectangle" 
                Storyboard.TargetProperty="Width" 
                Duration="0:0:4" From="10" To="500"/>
            </Storyboard>

          </BeginStoryboard>
        </EventTrigger>
      </Rectangle.Triggers>
    </Rectangle>

    <!-- Use this slider to seek to different points of the Storyboard Duration 
         (in milliseconds). -->
    <Slider Name="SeekSlider" ValueChanged="OnSliderValueChanged" Height="Auto" 
    Width="500" Minimum="0" Maximum="4000" HorizontalAlignment="Left" />

    <!-- TextBlock displays the current time position of the Storyboard in milliseconds. -->
    <TextBlock Name="PositionTextBlock"/>
  </StackPanel>
</Page>

Di seguito viene fornito il codice utilizzato con il codice XAML riportato sopra.

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

namespace SDKSample
{

    public partial class SeekStoryboardSynchronouslyExample : Page
    {
        private void OnSliderValueChanged(object sender, RoutedEventArgs e)
        {
            int sliderValue = (int)SeekSlider.Value;

            // The SeekAlignedToLastTick method should be used to seek a Storyboard synchronously.
            myStoryboard.SeekAlignedToLastTick(myRectangle, new TimeSpan(0, 0, 0, 0, sliderValue), TimeSeekOrigin.BeginTime);
            PositionTextBlock.Text = sliderValue.ToString();
        }
    }

}