Cómo: Recibir una notificación cuando se complete una escala de tiempo
Actualización: noviembre 2007
El evento Completed le avisa cuando se completa Timeline. Se considera que una escala de tiempo se ha completado después de haber alcanzado el fin de su período activo y no se va a reproducir a menos que se reinicie de manera interactiva. Observe que "completarse" no es lo mismo que "detener la reproducción": cuando se detiene la reproducción de una escala de tiempo, no se activa el evento Completed (en cambio, sí se activa si se salta hasta el período de relleno de la misma).
Ejemplo
En el ejemplo siguiente, dos objetos Storyboard se utilizan para crear una transición de animación entre dos imágenes, se almacenan mediante objetos ImageSource y se muestran mediante un control Image. Un guión gráfico reduce el control de imagen hasta que desaparece. Después de completarse, el objeto ImageSource anterior se intercambia con el otro objeto ImageSource y se utiliza un segundo guión gráfico que expande el control de imagen hasta que recupera su tamaño completo.
<!-- TimelineCompletedExample.xaml
This example creates an animated transition between
two images. When the user clicks the Start Transition button,
a storyboard shrinks an image until it disappears.
The Completed event is used to notify the class when this
storyboard has completed. The code behind file handles
this event by swapping the image and making it visible again.
-->
<Page xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml"
x:Class="SDKSample.TimelineCompletedExample"
WindowTitle="Timeline Completed Example"
Loaded="exampleLoaded">
<Page.Resources>
<!-- A simple picture of a rectangle. -->
<DrawingImage x:Key="RectangleDrawingImage">
<DrawingImage.Drawing>
<DrawingGroup>
<GeometryDrawing Brush="White">
<GeometryDrawing.Geometry>
<RectangleGeometry Rect="0,0,100,100" />
</GeometryDrawing.Geometry>
</GeometryDrawing>
<GeometryDrawing Brush="Orange">
<GeometryDrawing.Geometry>
<RectangleGeometry Rect="25,25,50,50" />
</GeometryDrawing.Geometry>
</GeometryDrawing>
</DrawingGroup>
</DrawingImage.Drawing>
</DrawingImage>
<!-- A simple picture of a cirlce. -->
<DrawingImage x:Key="CircleDrawingImage">
<DrawingImage.Drawing>
<DrawingGroup>
<GeometryDrawing Brush="White">
<GeometryDrawing.Geometry>
<RectangleGeometry Rect="0,0,100,100" />
</GeometryDrawing.Geometry>
</GeometryDrawing>
<GeometryDrawing>
<GeometryDrawing.Geometry>
<EllipseGeometry Center="50,50" RadiusX="25" RadiusY="25" />
</GeometryDrawing.Geometry>
<GeometryDrawing.Brush>
<RadialGradientBrush GradientOrigin="0.75,0.25" Center="0.75,0.25">
<GradientStop Offset="0.0" Color="White" />
<GradientStop Offset="1.0" Color="LimeGreen" />
</RadialGradientBrush>
</GeometryDrawing.Brush>
</GeometryDrawing>
</DrawingGroup>
</DrawingImage.Drawing>
</DrawingImage>
<!-- Define the storyboard that enlarges the image.
This storyboard is applied using code when
ZoomOutStoryboard completes. -->
<Storyboard x:Key="ZoomInStoryboardResource">
<DoubleAnimation
Storyboard.TargetName="AnimatedImageScaleTranform"
Storyboard.TargetProperty="ScaleX"
Duration="0:0:5" To="1" />
<DoubleAnimation
Storyboard.TargetName="AnimatedImageScaleTranform"
Storyboard.TargetProperty="ScaleY"
Duration="0:0:5" To="1" />
</Storyboard>
</Page.Resources>
<StackPanel Margin="20" >
<Border
BorderBrush="Gray" BorderThickness="2"
HorizontalAlignment="Center" VerticalAlignment="Center">
<!-- Displays the current ImageSource. -->
<Image
Name="AnimatedImage"
Width="200" Height="200"
RenderTransformOrigin="0.5,0.5">
<Image.RenderTransform>
<ScaleTransform x:Name="AnimatedImageScaleTranform"
ScaleX="1" ScaleY="1" />
</Image.RenderTransform>
</Image>
</Border>
<!-- This StackPanel contains buttons that control the storyboard. -->
<StackPanel Orientation="Horizontal" Margin="0,30,0,0">
<Button Name="BeginButton">Start Transition</Button>
<Button Name="SkipToFillButton">Skip To Fill</Button>
<Button Name="StopButton">Stop</Button>
<StackPanel.Triggers>
<!-- Begin the storyboard that shrinks the image. After the storyboard
completes, -->
<EventTrigger RoutedEvent="Button.Click" SourceName="BeginButton">
<BeginStoryboard Name="ZoomOutBeginStoryboard">
<Storyboard x:Name="ZoomOutStoryboard"
Completed="zoomOutStoryboardCompleted" FillBehavior="Stop">
<DoubleAnimation
Storyboard.TargetName="AnimatedImageScaleTranform"
Storyboard.TargetProperty="ScaleX"
Duration="0:0:5" To="0" FillBehavior="Stop" />
<DoubleAnimation
Storyboard.TargetName="AnimatedImageScaleTranform"
Storyboard.TargetProperty="ScaleY"
Duration="0:0:5" To="0" FillBehavior="Stop" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
<!-- Advances ZoomOutStoryboard to its fill period.
This action triggers the Completed event. -->
<EventTrigger RoutedEvent="Button.Click" SourceName="SkipToFillButton">
<SkipStoryboardToFill BeginStoryboardName="ZoomOutBeginStoryboard" />
</EventTrigger>
<!-- Stops the storyboard. This action does not
trigger the completed event. -->
<EventTrigger RoutedEvent="Button.Click" SourceName="StopButton">
<StopStoryboard BeginStoryboardName="ZoomOutBeginStoryboard" />
</EventTrigger>
</StackPanel.Triggers>
</StackPanel>
</StackPanel>
</Page>
// TimelineCompletedExample.xaml.cs
// Handles the ZoomOutStoryboard's Completed event.
// See the TimelienCompletedExample.xaml file
// for the markup that creates the images and storyboards.
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Navigation;
namespace SDKSample
{
public partial class TimelineCompletedExample : Page
{
private Storyboard zoomInStoryboard;
private ImageSource currentImageSource;
private ImageSource nextImageSource;
public TimelineCompletedExample()
{
InitializeComponent();
}
private void exampleLoaded(object sender, RoutedEventArgs e)
{
// Cache the zoom-out storyboard resource.
zoomInStoryboard =
(Storyboard) this.Resources["ZoomInStoryboardResource"];
// Cache the ImageSource resources.
currentImageSource =
(ImageSource) this.Resources["RectangleDrawingImage"];
nextImageSource =
(ImageSource) this.Resources["CircleDrawingImage"];
// Display the current image source.
AnimatedImage.Source = currentImageSource;
}
// Handles the zoom-out storyboard's completed event.
private void zoomOutStoryboardCompleted(object sender, EventArgs e)
{
AnimatedImage.Source = nextImageSource;
nextImageSource = currentImageSource;
currentImageSource = AnimatedImage.Source;
zoomInStoryboard.Begin(AnimatedImage, HandoffBehavior.SnapshotAndReplace);
}
}
}
Para obtener más información acerca de los eventos de control de tiempo, vea Información general sobre eventos de control de tiempo.