如何:对 ArcSegment 的大小进行动画处理

更新:2007 年 11 月

此示例演示如何对 ArcSegmentSize 属性进行动画处理。

示例

下面的示例创建一个 ArcSegment,在屏幕上加载此类时,它会对其 Size 进行动画处理。

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

namespace SDKSamples
{
    public class SizeAnimationExample : Page
    {
        public SizeAnimationExample()
        {

            // Create a NameScope for this page so that
            // Storyboards can be used.
            NameScope.SetNameScope(this, new NameScope());

            // Create an ArcSegment to define the geometry of the path.
            // The Size property of this segment is animated.
            ArcSegment myArcSegment = new ArcSegment();
            myArcSegment.Size = new Size(90, 80);
            myArcSegment.SweepDirection = SweepDirection.Clockwise;
            myArcSegment.Point = new Point(500, 200);

            // Assign the segment a name so that
            // it can be targeted by a Storyboard.
            this.RegisterName(
                "myArcSegment", myArcSegment);

            PathSegmentCollection myPathSegmentCollection = new PathSegmentCollection();
            myPathSegmentCollection.Add(myArcSegment);

            // Create a PathFigure to be used for the PathGeometry of myPath.
            PathFigure myPathFigure = new PathFigure();

            // Set the starting point for the PathFigure specifying that the
            // geometry starts at point 100,200.
            myPathFigure.StartPoint = new Point(100, 200);

            myPathFigure.Segments = myPathSegmentCollection;

            PathFigureCollection myPathFigureCollection = new PathFigureCollection();
            myPathFigureCollection.Add(myPathFigure);

            PathGeometry myPathGeometry = new PathGeometry();
            myPathGeometry.Figures = myPathFigureCollection;

            // Create a path to draw a geometry with.
            Path myPath = new Path();
            myPath.Stroke = Brushes.Black;
            myPath.StrokeThickness = 1;

            // specify the shape of the path using the path geometry.
            myPath.Data = myPathGeometry;

            SizeAnimation mySizeAnimation = new SizeAnimation();
            mySizeAnimation.Duration = TimeSpan.FromSeconds(2);

            // Set the animation to repeat forever. 
            mySizeAnimation.RepeatBehavior = RepeatBehavior.Forever;

            // Set the From and To properties of the animation.
            mySizeAnimation.From = new Size(90, 80);
            mySizeAnimation.To = new Size(200, 200);

            // Set the animation to target the Size property
            // of the object named "myArcSegment."
            Storyboard.SetTargetName(mySizeAnimation, "myArcSegment");
            Storyboard.SetTargetProperty(
                mySizeAnimation, new PropertyPath(ArcSegment.SizeProperty));

            // Create a storyboard to apply the animation.
            Storyboard ellipseStoryboard = new Storyboard();
            ellipseStoryboard.Children.Add(mySizeAnimation);

            // Start the storyboard when the Path loads.
            myPath.Loaded += delegate(object sender, RoutedEventArgs e)
            {
                ellipseStoryboard.Begin(this);
            };

            Canvas containerCanvas = new Canvas();
            containerCanvas.Children.Add(myPath);

            Content = containerCanvas;
        }
    }
}
<Page xmlns="https://schemas.microsoft.com/winfx/2006/xaml/presentation" 
  xmlns:x="https://schemas.microsoft.com/winfx/2006/xaml" >
    <Canvas HorizontalAlignment="Left" Margin="0" >

      <!-- Create an arc on the screen that animates its size when it loads. -->
      <Path Stroke="Black" StrokeThickness="2" >
        <Path.Data>
          <PathGeometry>
            <PathGeometry.Figures>
              <PathFigureCollection>
                <PathFigure StartPoint="100,200">
                  <PathFigure.Segments>
                    <PathSegmentCollection>
                      <ArcSegment x:Name="myArcSegment" Size="90,80" 
                      SweepDirection="Clockwise"  Point="500,200" />
                    </PathSegmentCollection>
                  </PathFigure.Segments>
                </PathFigure>
              </PathFigureCollection>
            </PathGeometry.Figures>
          </PathGeometry>
        </Path.Data>
        <Path.Triggers>
          <EventTrigger RoutedEvent="Path.Loaded">
            <BeginStoryboard Name="myBeginStoryBoard">
              <Storyboard>

                <!-- Animate the size of the ArcSegment to a width and height of 200. -->
                <SizeAnimation
                Storyboard.TargetName="myArcSegment"
                Storyboard.TargetProperty="Size"
                From="90,80"
                To="200,200"
                Duration="0:0:2" />

              </Storyboard>
            </BeginStoryboard>
          </EventTrigger>
        </Path.Triggers>
      </Path>
    </Canvas>

</Page>

有关其他几何和动画示例,请参见几何图形示例

请参见

概念

动画概述

Geometry 概述

参考

Size

ArcSegment

其他资源

几何图形帮助主题

几何图形示例

动画和计时

动画和计时帮助主题

动画和计时示例