Cómo: Animar un objeto Double mediante fotogramas clave
En este ejemplo se muestra cómo animar el valor de una propiedad que adopta un objeto Double mediante fotogramas clave.
Ejemplo
En el ejemplo siguiente se mueve un rectángulo por una pantalla. En el ejemplo siguiente se usa la clase DoubleAnimationUsingKeyFrames para animar la propiedad X de un TranslateTransform aplicada a un Rectangle. Esta animación, que se repite indefinidamente, utiliza tres fotogramas clave de la manera siguiente:
Durante los primeros tres segundos, utiliza una instancia de la clase LinearDoubleKeyFrame para mover el rectángulo a lo largo de un trazado a ritmo constante desde su posición inicial hasta la posición 500. Los fotogramas clave lineales como LinearDoubleKeyFrame crean una transición lineal suave entre valores.
Al final del cuarto segundo, utiliza una instancia de la clase DiscreteDoubleKeyFrame para mover repentinamente el rectángulo a la posición siguiente. Los fotogramas clave discretos como DiscreteDoubleKeyFrame crean saltos repentinos entre valores. En este ejemplo, el rectángulo está en la posición inicial y aparece de pronto en la posición 500.
En los últimos dos segundos, utiliza una instancia de la clase SplineDoubleKeyFrame para mover el rectángulo de nuevo a su posición inicial. Los fotogramas clave de spline como SplineDoubleKeyFrame crean una transición variable entre valores según el valor de la propiedad KeySpline. En este ejemplo, el rectángulo comienza a moverse despacio y se acelera exponencialmente hacia el final del segmento temporal.
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Shapes;
using System.Windows.Media.Animation;
using System.Windows.Media;
namespace Microsoft.Samples.KeyFrameExamples
{
/// <summary>
/// This example shows how to use the DoubleAnimationUsingKeyFrames class to
/// animate the position of an object.
/// Key frame animations enable you to create complex animations
/// by specifying multiple destination values
/// and controlling the animation's interpolation method.
/// </summary>
public class AltDoubleAnimationUsingKeyFramesExample : Page
{
public AltDoubleAnimationUsingKeyFramesExample()
{
Title = "DoubleAnimationUsingKeyFrames Example";
Background = Brushes.White;
Margin = new Thickness(20);
// Create a NameScope for this page so that
// Storyboards can be used.
NameScope.SetNameScope(this, new NameScope());
// Create a rectangle.
Rectangle aRectangle = new Rectangle();
aRectangle.Width = 100;
aRectangle.Height = 100;
aRectangle.Stroke = Brushes.Black;
aRectangle.StrokeThickness = 5;
// Create a Canvas to contain and
// position the rectangle.
Canvas containerCanvas = new Canvas();
containerCanvas.Width = 610;
containerCanvas.Height = 300;
containerCanvas.Children.Add(aRectangle);
Canvas.SetTop(aRectangle, 100);
Canvas.SetLeft(aRectangle, 10);
// Create a TranslateTransform to
// move the rectangle.
TranslateTransform animatedTranslateTransform =
new TranslateTransform();
aRectangle.RenderTransform = animatedTranslateTransform;
// Assign the TranslateTransform a name so that
// it can be targeted by a Storyboard.
this.RegisterName(
"AnimatedTranslateTransform", animatedTranslateTransform);
// Create a DoubleAnimationUsingKeyFrames to
// animate the TranslateTransform.
DoubleAnimationUsingKeyFrames translationAnimation
= new DoubleAnimationUsingKeyFrames();
translationAnimation.Duration = TimeSpan.FromSeconds(6);
// Animate from the starting position to 500
// over the first second using linear
// interpolation.
translationAnimation.KeyFrames.Add(
new LinearDoubleKeyFrame(
500, // Target value (KeyValue)
KeyTime.FromTimeSpan(TimeSpan.FromSeconds(3))) // KeyTime
);
// Animate from 500 (the value of the previous key frame)
// to 400 at 4 seconds using discrete interpolation.
// Because the interpolation is discrete, the rectangle will appear
// to "jump" from 500 to 400.
translationAnimation.KeyFrames.Add(
new DiscreteDoubleKeyFrame(
400, // Target value (KeyValue)
KeyTime.FromTimeSpan(TimeSpan.FromSeconds(4))) // KeyTime
);
// Animate from 400 (the value of the previous key frame) to 0
// over two seconds, starting at 4 seconds (the key time of the
// last key frame) and ending at 6 seconds.
translationAnimation.KeyFrames.Add(
new SplineDoubleKeyFrame(
0, // Target value (KeyValue)
KeyTime.FromTimeSpan(TimeSpan.FromSeconds(6)), // KeyTime
new KeySpline(0.6,0.0,0.9,0.0) // KeySpline
)
);
// Set the animation to repeat forever.
translationAnimation.RepeatBehavior = RepeatBehavior.Forever;
// Set the animation to target the X property
// of the object named "AnimatedTranslateTransform."
Storyboard.SetTargetName(translationAnimation, "AnimatedTranslateTransform");
Storyboard.SetTargetProperty(
translationAnimation, new PropertyPath(TranslateTransform.XProperty));
// Create a storyboard to apply the animation.
Storyboard translationStoryboard = new Storyboard();
translationStoryboard.Children.Add(translationAnimation);
// Start the storyboard after the rectangle loads.
aRectangle.Loaded += delegate(object sender, RoutedEventArgs e)
{
translationStoryboard.Begin(this);
};
Content = containerCanvas;
}
}
}
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Shapes
Imports System.Windows.Media.Animation
Imports System.Windows.Media
Namespace Microsoft.Samples.KeyFrameExamples
''' <summary>
''' This example shows how to use the DoubleAnimationUsingKeyFrames class to
''' animate the position of an object.
''' Key frame animations enable you to create complex animations
''' by specifying multiple destination values
''' and controlling the animation's interpolation method.
''' </summary>
Public Class AltDoubleAnimationUsingKeyFramesExample
Inherits Page
Public Sub New()
Title = "DoubleAnimationUsingKeyFrames Example"
Background = Brushes.White
Margin = New Thickness(20)
' Create a NameScope for this page so that
' Storyboards can be used.
NameScope.SetNameScope(Me, New NameScope())
' Create a rectangle.
Dim aRectangle As New Rectangle()
aRectangle.Width = 100
aRectangle.Height = 100
aRectangle.Stroke = Brushes.Black
aRectangle.StrokeThickness = 5
' Create a Canvas to contain and
' position the rectangle.
Dim containerCanvas As New Canvas()
containerCanvas.Width = 610
containerCanvas.Height = 300
containerCanvas.Children.Add(aRectangle)
Canvas.SetTop(aRectangle, 100)
Canvas.SetLeft(aRectangle, 10)
' Create a TranslateTransform to
' move the rectangle.
Dim animatedTranslateTransform As New TranslateTransform()
aRectangle.RenderTransform = animatedTranslateTransform
' Assign the TranslateTransform a name so that
' it can be targeted by a Storyboard.
Me.RegisterName("AnimatedTranslateTransform", animatedTranslateTransform)
' Create a DoubleAnimationUsingKeyFrames to
' animate the TranslateTransform.
Dim translationAnimation As New DoubleAnimationUsingKeyFrames()
translationAnimation.Duration = TimeSpan.FromSeconds(6)
' Animate from the starting position to 500
' over the first second using linear
' interpolation.
translationAnimation.KeyFrames.Add(New LinearDoubleKeyFrame(500, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(3)))) ' KeyTime - Target value (KeyValue)
' Animate from 500 (the value of the previous key frame)
' to 400 at 4 seconds using discrete interpolation.
' Because the interpolation is discrete, the rectangle will appear
' to "jump" from 500 to 400.
translationAnimation.KeyFrames.Add(New DiscreteDoubleKeyFrame(400, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(4)))) ' KeyTime - Target value (KeyValue)
' Animate from 400 (the value of the previous key frame) to 0
' over two seconds, starting at 4 seconds (the key time of the
' last key frame) and ending at 6 seconds.
translationAnimation.KeyFrames.Add(New SplineDoubleKeyFrame(0, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(6)), New KeySpline(0.6,0.0,0.9,0.0))) ' KeySpline - KeyTime - Target value (KeyValue)
' Set the animation to repeat forever.
translationAnimation.RepeatBehavior = RepeatBehavior.Forever
' Set the animation to target the X property
' of the object named "AnimatedTranslateTransform."
Storyboard.SetTargetName(translationAnimation, "AnimatedTranslateTransform")
Storyboard.SetTargetProperty(translationAnimation, New PropertyPath(TranslateTransform.XProperty))
' Create a storyboard to apply the animation.
Dim translationStoryboard As New Storyboard()
translationStoryboard.Children.Add(translationAnimation)
' Start the storyboard after the rectangle loads.
AddHandler aRectangle.Loaded, Sub(sender As Object, e As RoutedEventArgs) translationStoryboard.Begin(Me)
Content = containerCanvas
End Sub
End Class
End Namespace
<!-- This example shows how to use the DoubleAnimationUsingKeyFrames to
animate the position of an object.
Key frame animations enable you to create complex animations
by specifying multiple destination values
and controlling the animation's interpolation method.
-->
<Page
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="DoubleAnimationUsingKeyFrames Example"
Background="White" Margin="20">
<Canvas Width="610" Height="300">
<!-- The position of this rectangle is animated using
a key frame animation. -->
<Rectangle
Canvas.Top="100"
Canvas.Left="10"
Height="100"
Width="100"
Stroke="Black"
StrokeThickness="5">
<Rectangle.RenderTransform>
<TranslateTransform x:Name="AnimatedTranslateTransform" />
</Rectangle.RenderTransform>
<Rectangle.Triggers>
<EventTrigger RoutedEvent="Rectangle.Loaded">
<BeginStoryboard>
<Storyboard>
<!-- Animate the TranslateTransform.X property using 3 KeyFrames
which animates the rectangle along a straight line.
This animation repeats indefinitely. -->
<DoubleAnimationUsingKeyFrames
Storyboard.TargetName="AnimatedTranslateTransform"
Storyboard.TargetProperty="X"
Duration="0:0:6"
RepeatBehavior="Forever">
<!-- Using a LinearDoubleKeyFrame, the rectangle moves
steadily from its starting position to 500 over
the first 3 seconds. -->
<LinearDoubleKeyFrame Value="500" KeyTime="0:0:3" />
<!-- Using a DiscreteDoubleKeyFrame, the rectangle suddenly
appears at 400 after the fourth second of the animation. -->
<DiscreteDoubleKeyFrame Value="400" KeyTime="0:0:4" />
<!-- Using a SplineDoubleKeyFrame, the rectangle moves
back to its starting point. The
animation starts out slowly at first and then speeds up.
This KeyFrame ends after the 6th
second. -->
<SplineDoubleKeyFrame KeySpline="0.6,0.0 0.9,0.00" Value="0" KeyTime="0:0:6" />
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Rectangle.Triggers>
</Rectangle>
</Canvas>
</Page>
Para consultar el ejemplo completo, vea Ejemplo de animación mediante fotogramas clave.
Para ofrecer coherencia con otros ejemplos de animación, en las versiones de código de este ejemplo se utiliza un objeto Storyboard para aplicar DoubleAnimationUsingKeyFrames. Pero, al aplicar una sola animación en el código, es más fácil usar el método BeginAnimation en vez de un Storyboard. Para obtener un ejemplo, vea Animar una propiedad sin utilizar un guión gráfico.
Vea también
Colaborar con nosotros en GitHub
El origen de este contenido se puede encontrar en GitHub, donde también puede crear y revisar problemas y solicitudes de incorporación de cambios. Para más información, consulte nuestra guía para colaboradores.
.NET Desktop feedback
Comentarios
Próximamente: A lo largo de 2024 iremos eliminando gradualmente GitHub Issues como mecanismo de comentarios sobre el contenido y lo sustituiremos por un nuevo sistema de comentarios. Para más información, vea: https://aka.ms/ContentUserFeedback.
Enviar y ver comentarios de