没有适用的名称范围来解析名称'ellipse'

Question

我正在尝试WPF并在为我的“Othello Buttons”创建动画时遇到问题。

所以，我用一些属性创建了一个新的类Token : Button。我还添加了RessourceDictionary和StoryBoard。现在我想在Switch Case中启动它。当我这样做时，我收到以下错误：

  

没有适用的名称范围来解析名称'ellipse'。

 <!-- TOKEN TEMPLATE -->
<Style x:Key="Token" TargetType="{x:Type Button}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type Button}">
                <ControlTemplate.Resources>
                    <Storyboard x:Key="ToWhite">
                        <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="ellipse">
                            <EasingDoubleKeyFrame KeyTime="0" Value="0"/>
                            <EasingDoubleKeyFrame KeyTime="0:0:0.5" Value="1"/>
                        </DoubleAnimationUsingKeyFrames>
                        <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[0].(GradientStop.Color)" Storyboard.TargetName="ellipse">
                            <EasingColorKeyFrame KeyTime="0" Value="White"/>
                            <EasingColorKeyFrame KeyTime="0:0:0.5" Value="Black"/>
                        </ColorAnimationUsingKeyFrames>
                        <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="ellipse">
                            <EasingColorKeyFrame KeyTime="0" Value="Black"/>
                            <EasingColorKeyFrame KeyTime="0:0:0.5" Value="White"/>
                        </ColorAnimationUsingKeyFrames>
                    </Storyboard>
                    <Storyboard x:Key="ToBlack">
                        <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="ellipse">
                            <EasingDoubleKeyFrame KeyTime="0" Value="0"/>
                            <EasingDoubleKeyFrame KeyTime="0:0:0.5" Value="1"/>
                        </DoubleAnimationUsingKeyFrames>
                    </Storyboard>
                    <Storyboard x:Key="ToEnabled">
                        <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Shape.Fill).(GradientBrush.GradientStops)[1].(GradientStop.Color)" Storyboard.TargetName="ellipse">
                            <EasingColorKeyFrame KeyTime="0" Value="Black"/>
                            <EasingColorKeyFrame KeyTime="0:0:0.5" Value="White"/>
                        </ColorAnimationUsingKeyFrames>
                        <DoubleAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="ellipse">
                            <EasingDoubleKeyFrame KeyTime="0" Value="0"/>
                            <EasingDoubleKeyFrame KeyTime="0:0:0.5" Value="0.19"/>
                        </DoubleAnimationUsingKeyFrames>
                    </Storyboard>
                </ControlTemplate.Resources>

这是我的令牌类

public class Token : Button
{
    Storyboard sbToWhite = new Storyboard();
    Storyboard sbToBlack = new Storyboard();
    Storyboard sbToEnabled = new Storyboard();

    public Token()
    {
        BorderBrush = new SolidColorBrush(Colors.Gainsboro);

        sbToBlack = (Storyboard)TryFindResource("ToBlack");
        sbToEnabled = (Storyboard)TryFindResource("ToEnabled");;
    }

    private GameState.TokenState _status;

    public Point Point { get; set; }

    public GameState.TokenState Status { get { return _status; } 
    set
    {
        _status = value;
        switch (value)
        {
            case GameState.TokenState.NONE:
                IsSet = false;
                break;
            case GameState.TokenState.WHITE:
                ((Storyboard)TryFindResource("ToWhite")).Begin();
                IsSet = true;
                break;
            case GameState.TokenState.BLACK:
                sbToBlack.Begin();
                IsSet = true;
                break;
            case GameState.TokenState.ENABLED:
                sbToEnabled.Begin();
                IsSet = false;
                break;
        }
    }