Procedura: animare un oggetto lungo un percorso (animazione Matrix con accumulazione offset)
In questo esempio viene illustrato come utilizzare la classe MatrixAnimationUsingPath per animare un oggetto lungo un percorso e fare in modo che l'animazione accumuli i valori di offset durante la ripetizione.
Esempio
Nell'esempio riportato di seguito viene utilizzato l'oggetto MatrixAnimationUsingPath per animare la proprietà Matrix di una classe MatrixTransform applicata a un pulsante. Di conseguenza, un pulsante viene spostato lungo un percorso curvo.
Inoltre, nell'esempio la proprietà IsOffsetCumulative viene impostata su true, così che l'offset della matrice animata si accumuli man mano che l'animazione viene ripetuta. Data l'accumulazione dell'offset, il pulsante viene spostato ulteriormente in avanti sullo schermo quando l'animazione viene ripetuta, anziché essere reimpostato sulla posizione iniziale.
<Page
xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml" Margin="20"
xmlns:PresentationOptions="https://schemas.microsoft.com/winfx/2006/xaml/presentation/options"
xmlns:mc="https://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="PresentationOptions">
<Canvas Width="400" Height="400">
<!-- The Button that is animated across the screen by animating
the MatrixTransform applied to the button. -->
<Button MinWidth="100" Content="A Button">
<Button.RenderTransform>
<MatrixTransform x:Name="myMatrixTransform">
<MatrixTransform.Matrix >
<Matrix />
</MatrixTransform.Matrix>
</MatrixTransform>
</Button.RenderTransform>
<Button.Triggers>
<EventTrigger RoutedEvent="Button.Click">
<BeginStoryboard>
<Storyboard>
<MatrixAnimationUsingPath
Storyboard.TargetName="myMatrixTransform"
Storyboard.TargetProperty="Matrix"
IsOffsetCumulative="True"
Duration="0:0:5"
RepeatBehavior="2x">
<MatrixAnimationUsingPath.PathGeometry>
<PathGeometry
Figures="M 10,100 C 35,0 135,0 160,100 180,190 285,200 310,100"
PresentationOptions:Freeze="True" />
</MatrixAnimationUsingPath.PathGeometry>
</MatrixAnimationUsingPath>
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Button.Triggers>
</Button>
</Canvas>
</Page>
Imports System
Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Media.Animation
Imports System.Windows.Navigation
Imports System.Windows.Shapes
Namespace SDKSample
''' <summary>
''' Shows how to use the MatrixAnimationUsingPath.IsOffsetCumulative
''' property to make a MatrixAnimatioinUsingPath accumulate
''' its values when it repeats.
''' </summary>
Public Class MatrixAnimationUsingPathExampleOffsetCumulative
Inherits Page
Public Sub New()
Me.Margin = New Thickness(20)
' Create a NameScope for the page so that
' we can use Storyboards.
NameScope.SetNameScope(Me, New NameScope())
' Create a button.
Dim aButton As New Button()
aButton.MinWidth = 100
aButton.Content = "A Button"
' Create a MatrixTransform. This transform
' will be used to move the button.
Dim buttonMatrixTransform As New MatrixTransform()
aButton.RenderTransform = buttonMatrixTransform
' Register the transform's name with the page
' so that it can be targeted by a Storyboard.
Me.RegisterName("ButtonMatrixTransform", buttonMatrixTransform)
' Create a Canvas to contain the button
' and add it to the page.
' Although this example uses a Canvas,
' any type of panel will work.
Dim mainPanel As New Canvas()
mainPanel.Width = 400
mainPanel.Height = 400
mainPanel.Children.Add(aButton)
Me.Content = mainPanel
' Create the animation path.
Dim animationPath As New PathGeometry()
Dim pFigure As New PathFigure()
pFigure.StartPoint = New Point(10, 100)
Dim pBezierSegment As New PolyBezierSegment()
pBezierSegment.Points.Add(New Point(35, 0))
pBezierSegment.Points.Add(New Point(135, 0))
pBezierSegment.Points.Add(New Point(160, 100))
pBezierSegment.Points.Add(New Point(180, 190))
pBezierSegment.Points.Add(New Point(285, 200))
pBezierSegment.Points.Add(New Point(310, 100))
pFigure.Segments.Add(pBezierSegment)
animationPath.Figures.Add(pFigure)
' Freeze the PathGeometry for performance benefits.
animationPath.Freeze()
' Create a MatrixAnimationUsingPath to move the
' button along the path by animating
' its MatrixTransform.
Dim matrixAnimation As New MatrixAnimationUsingPath()
matrixAnimation.PathGeometry = animationPath
' Set IsOffsetCumulative to true so that the animation
' values accumulate when its repeats.
matrixAnimation.IsOffsetCumulative = True
matrixAnimation.Duration = TimeSpan.FromSeconds(5)
matrixAnimation.RepeatBehavior = New RepeatBehavior(2)
' Set the animation to target the Matrix property
' of the MatrixTransform named "ButtonMatrixTransform".
Storyboard.SetTargetName(matrixAnimation, "ButtonMatrixTransform")
Storyboard.SetTargetProperty(matrixAnimation, New PropertyPath(MatrixTransform.MatrixProperty))
' Create a Storyboard to contain and apply the animation.
Dim pathAnimationStoryboard As New Storyboard()
pathAnimationStoryboard.Children.Add(matrixAnimation)
' Start the animation when the button is clicked.
AddHandler aButton.Click, Sub(sender As Object, e As RoutedEventArgs) pathAnimationStoryboard.Begin(Me)
End Sub
End Class
End Namespace
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace SDKSample
{
/// <summary>
/// Shows how to use the MatrixAnimationUsingPath.IsOffsetCumulative
/// property to make a MatrixAnimatioinUsingPath accumulate
/// its values when it repeats.
/// </summary>
public class MatrixAnimationUsingPathExampleOffsetCumulative : Page
{
public MatrixAnimationUsingPathExampleOffsetCumulative()
{
this.Margin = new Thickness(20);
// Create a NameScope for the page so that
// we can use Storyboards.
NameScope.SetNameScope(this, new NameScope());
// Create a button.
Button aButton = new Button();
aButton.MinWidth = 100;
aButton.Content = "A Button";
// Create a MatrixTransform. This transform
// will be used to move the button.
MatrixTransform buttonMatrixTransform = new MatrixTransform();
aButton.RenderTransform = buttonMatrixTransform;
// Register the transform's name with the page
// so that it can be targeted by a Storyboard.
this.RegisterName("ButtonMatrixTransform", buttonMatrixTransform);
// Create a Canvas to contain the button
// and add it to the page.
// Although this example uses a Canvas,
// any type of panel will work.
Canvas mainPanel = new Canvas();
mainPanel.Width = 400;
mainPanel.Height = 400;
mainPanel.Children.Add(aButton);
this.Content = mainPanel;
// Create the animation path.
PathGeometry animationPath = new PathGeometry();
PathFigure pFigure = new PathFigure();
pFigure.StartPoint = new Point(10, 100);
PolyBezierSegment pBezierSegment = new PolyBezierSegment();
pBezierSegment.Points.Add(new Point(35, 0));
pBezierSegment.Points.Add(new Point(135, 0));
pBezierSegment.Points.Add(new Point(160, 100));
pBezierSegment.Points.Add(new Point(180, 190));
pBezierSegment.Points.Add(new Point(285, 200));
pBezierSegment.Points.Add(new Point(310, 100));
pFigure.Segments.Add(pBezierSegment);
animationPath.Figures.Add(pFigure);
// Freeze the PathGeometry for performance benefits.
animationPath.Freeze();
// Create a MatrixAnimationUsingPath to move the
// button along the path by animating
// its MatrixTransform.
MatrixAnimationUsingPath matrixAnimation =
new MatrixAnimationUsingPath();
matrixAnimation.PathGeometry = animationPath;
// Set IsOffsetCumulative to true so that the animation
// values accumulate when its repeats.
matrixAnimation.IsOffsetCumulative = true;
matrixAnimation.Duration = TimeSpan.FromSeconds(5);
matrixAnimation.RepeatBehavior = new RepeatBehavior(2);
// Set the animation to target the Matrix property
// of the MatrixTransform named "ButtonMatrixTransform".
Storyboard.SetTargetName(matrixAnimation, "ButtonMatrixTransform");
Storyboard.SetTargetProperty(matrixAnimation,
new PropertyPath(MatrixTransform.MatrixProperty));
// Create a Storyboard to contain and apply the animation.
Storyboard pathAnimationStoryboard = new Storyboard();
pathAnimationStoryboard.Children.Add(matrixAnimation);
// Start the animation when the button is clicked.
aButton.Click += delegate(object sender, RoutedEventArgs e)
{
// Start the storyboard.
pathAnimationStoryboard.Begin(this);
};
}
}
}
Si noti che la proprietà IsOffsetCumulative causa l'accumulazione dei valori di offset nel corso delle ripetizioni, ma non l'accumulazione dei valori di rotazione. Per accumulare i valori di rotazione, impostare le proprietà DoesRotateWithTangent e IsAngleCumulative dell'animazione su true.
Per l'esempio completo, vedere Esempio di animazione percorso (la pagina potrebbe essere in inglese). Per un esempio relativo all'animazione di un valore Matrix lungo un percorso senza accumulazione offset, vedere Procedura: animare un oggetto lungo un percorso (animazione Matrix).
Vedere anche
Concetti
Cenni preliminari sull'animazione