如何创建基于BindableProperty变化的FadeTo()动画，MVVM风格？

// ViewModel定义
public class MyViewModel : BindableObject
{
    public static readonly BindableProperty OpacityProperty =
        BindableProperty.Create(nameof(Opacity), typeof(double), typeof(MyViewModel), default(double));

    public double Opacity
    {
        get { return (double)GetValue(OpacityProperty); }
        set { SetValue(OpacityProperty, value); }
    }
}

// XAML视图
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:YourNamespace"
             x:Class="YourNamespace.YourPage">
    <ContentPage.BindingContext>
        <local:MyViewModel/>
    </ContentPage.BindingContext>

    <ContentPage.Triggers>
        <EventTrigger Event="PropertyChanged">
            <EventTrigger.Actions>
                <local:FadeToAnimationAction TargetProperty="Opacity"
                                             TargetObject="{Binding}"
                                             Duration="1000"/>
            </EventTrigger.Actions>
        </EventTrigger>
    </ContentPage.Triggers>

    <StackLayout>
        <Label Text="Hello, World!"
               Opacity="{Binding Opacity}"/>
    </StackLayout>
</ContentPage>

// FadeTo动画触发器
public class FadeToAnimationAction : TriggerAction<BindableObject>
{
    public static readonly BindableProperty TargetPropertyProperty =
        BindableProperty.Create(nameof(TargetProperty), typeof(string), typeof(FadeToAnimationAction), default(string));

    public static readonly BindableProperty TargetObjectProperty =
        BindableProperty.Create(nameof(TargetObject), typeof(BindableObject), typeof(FadeToAnimationAction), default(BindableObject));

    public static readonly BindableProperty DurationProperty =
        BindableProperty.Create(nameof(Duration), typeof(uint), typeof(FadeToAnimationAction), (uint)250);

    public string TargetProperty
    {
        get { return (string)GetValue(TargetPropertyProperty); }
        set { SetValue(TargetPropertyProperty, value); }
    }

    public BindableObject TargetObject
    {
        get { return (BindableObject)GetValue(TargetObjectProperty); }
        set { SetValue(TargetObjectProperty, value); }
    }

    public uint Duration
    {
        get { return (uint)GetValue(DurationProperty); }
        set { SetValue(DurationProperty, value); }
    }

    protected override void Invoke(BindableObject bindable)
    {
        if (bindable is MyViewModel viewModel && TargetObject != null)
        {
            double endOpacity = viewModel.Opacity;

            // 创建FadeTo动画效果
            var animation = new Animation(v => TargetObject.SetValue(TargetProperty, v, BindingMode.Default, null, null), 0, endOpacity);

            animation.Commit(TargetObject, TargetProperty, 16, Duration, Easing.Linear, null, null);
        }
    }
}