WP8中的PropertyChangedTrigger不工作

Question

我需要创建一个百分比加载器控件。我创建了一个双弧控件。一个弧用于背景，一个弧用于前景。我将给出端点角作为弧的输入。我写了一个双动画类来执行加载动画。当我试图在代码中调用故事板时，动画工作了。

但是我的要求是，每当属性改变时，我需要加载加载器。所以我决定使用PropertyChangedBehaviour。但动画并不奏效。请建议最好的方法来做这件事

下面是xaml代码:

<VisualStateManager.VisualStateGroups>
        <VisualStateGroup x:Name="ValueStates">
            <VisualState x:Name="On">
                <Storyboard x:Name="storyBoard2">
                    <DoubleAnimation Duration="0:0:9" To="270" Storyboard.TargetProperty="(Arc.EndAngle)" Storyboard.TargetName="TimerProgressBar">
                        <DoubleAnimation.EasingFunction>
                            <ExponentialEase EasingMode="EaseOut"/>
                        </DoubleAnimation.EasingFunction>
                    </DoubleAnimation>
                </Storyboard>
            </VisualState>
        </VisualStateGroup>
    </VisualStateManager.VisualStateGroups>
            <Grid Grid.Row="1"
                  Background="Transparent"
                  HorizontalAlignment="Center"
                  VerticalAlignment="Top"
                  Margin="0 40 0 0">
                <i:Interaction.Triggers>
                    <ec:PropertyChangedTrigger Binding="{Binding EndAngleValue}">
                        <ec:GoToStateAction StateName="On"/>
                    </ec:PropertyChangedTrigger>
                </i:Interaction.Triggers>
                <es:Arc ArcThickness="1"
                        Fill="{StaticResource OlaTextLightGrayBrush}"
                        ArcThicknessUnit="Pixel"
                        Stretch="None"
                        Stroke="{StaticResource OlaTextLightGrayBrush}"
                        StartAngle="0"
                        EndAngle="360"
                        UseLayoutRounding="False"
                        Width="297"
                        Height="297" />
                <es:Arc ArcThickness="4"
                        Fill="{StaticResource OlaGreenBrush}"
                        x:Name="TimerProgressBar"
                        ArcThicknessUnit="Pixel"
                        Stretch="None"
                        StartAngle="0"
                        UseLayoutRounding="False"
                        Width="300"
                        Height="300" VerticalAlignment="Bottom" d:LayoutOverrides="Height" >
                    <es:Arc.Stroke>
                        <SolidColorBrush 
                            Color="{StaticResource OlaGreen}"/>
                    </es:Arc.Stroke>
                </es:Arc>

My View Model:

public double EndAngleValue
    {
        get
        {
            return _EndAngleValue;
        }
        set
        {
            SetProperty(ref _EndAngleValue, value);
        }
    }

当属性'危害值'改变时，我需要执行动画。

欢迎提出建议

Answer 1

如果你已经实现了，那么你应该能够这样做:

public double EndAngleValue
{
    get
    {
        return _EndAngleValue;
    }
    set
    {
        SetProperty(ref _EndAngleValue, value);
        OnPropertyChanged("EndAngleValue");
    }
}
private OnPropertyChanged(string propertyName)
{
    if(PropertyChanged != null)
    {
        PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
    }
}