Silverlight 不透明动画无法以编程方式工作

Question

我是 Silverlight 的新手，正在尝试以编程方式为对象的不透明度设置动画的示例。

我想出了以下代码：

        MapShape myTestShape= RadMapInformationLayer.Items[0] as MapShape;
        SolidColorBrush brush = new SolidColorBrush();
        brush.Color = Colors.Purple;
        myTestShape.Fill = brush;

        //create a duration object
        Duration duration = new Duration(TimeSpan.FromSeconds(5));

        //create the storyboard
        Storyboard story = new Storyboard();

        //create double animation
        DoubleAnimation animation = new DoubleAnimation();

        //set the duration property
        animation.Duration = duration;

        //set the from and too values
        animation.From = 1.0;
        animation.To = 0.0;

        //add the duration to the storyboard
        story.Duration = duration;            

        //now set the target of the animation
        Storyboard.SetTarget(animation, myTestShape);

        //set the target property of this object
        Storyboard.SetTargetProperty(animation, new PropertyPath(UIElement.OpacityProperty));

        //add the double animations to the story board
        story.Children.Add(animation);            

        if (!LayoutRoot.Resources.Contains("story1"))
            LayoutRoot.Resources.Add("story1", story);

        story.Begin();

对于我也尝试过的属性路径：

1.  new PropertyPath("(FrameworkElement.Opacity)")

2.  new PropertyPath("(FrameworkElement.Opacity)")

3.  new PropertyPath("(Control.Opacity)")

还有其他一些人，我对此的运气为零。

谁能看出我哪里出错了？

谢谢， 雅克

Answer 1

我之前已经对 MapShape.FillProperty 进行了数据绑定。

试试：

        //create double animation
        ColorAnimation animation = new ColorAnimation();

        //set the duration property
        animation.Duration = duration;

        //set the from and too values
        animation.From = Colors.Purple;
        animation.To = Colors.Transparent;

        //add the duration to the storyboard
        story.Duration = duration;

        //now set the target of the animation
        Storyboard.SetTarget(animation, rect);

        //set the target property of this object
        Storyboard.SetTargetProperty(animation, new PropertyPath("(MapShape.Fill).Color"));

编辑：

至于为什么您的代码不工作 - 查看 MapShape.SetShapeFillStroke()，看来 Telerik 不会将 MapShape 的不透明度绑定到其内部原始形状的不透明度，除非您提供填充。您是否在 XAML 中定义了填充？如果没有，请尝试提供一个。否则，可能代码在 Shape 的生命周期中定义得太早（在 ReadCompleted 中或之后）？

<telerik:InformationLayer x:Name="StateLayer">
    <telerik:InformationLayer.Reader>
        ...
    </telerik:InformationLayer.Reader>
    <telerik:InformationLayer.ShapeFill>
        <telerik:MapShapeFill Fill="{StaticResource CommonBackgroundLightBrush}" Stroke="#5A636B" StrokeThickness="1" />
    </telerik:InformationLayer.ShapeFill>