动态添加的控件，出现时候添加动画

C# code

 Floor floor = new Floor();                                 floor.Height = 10;                floor.Width = 10;                double delt = 2 * i * Math.PI / buildings.Count;                this.LayoutRoot.Children.Add(floor);                double X = CenterX - floor.Width / 2 + 50 * Math.Cos(delt);                double Y = CenterY - floor.Height / 2 + 50 * Math.Sin(delt);                Canvas.SetLeft(floor, X);                Canvas.SetTop(floor, Y);

这个是我后台添加的一个小圈，如何在它加入的时候显示一些动画？

C# code

Storyboard storyboard = new Storyboard();                //storyboard.Duration = new Duration(TimeSpan.FromSeconds(0.5));                DoubleAnimation slideOut = new DoubleAnimation();                slideOut.SetValue(Storyboard.TargetNameProperty, "floor");                slideOut.SetValue(Storyboard.TargetPropertyProperty, new PropertyPath("(UIElement.Opacity)"));                                slideOut.Duration = new Duration(TimeSpan.FromSeconds(0.5));                slideOut.To = 0;                slideOut.From = 1;                storyboard.Children.Add(slideOut);                LayoutRoot.Resources.Add("Storyboard", storyboard);                storyboard.Begin();

我这样添加还是会报错，无法解析 TargetName

[解决办法]
把动画加到floor.Loaded的事件里。