如何从iOS customrenderer访问PCL渲染器中的BindableProperty

public class BtnRenderer : Button
{

    public static readonly BindableProperty HighLightProperty = BindableProperty.Create(nameof(HighlightedBackgroundColor), typeof(Color), typeof(BtnRenderer), default(Color));

    public Color HighlightedBackgroundColor
    {
        get
        {
            return (Color)GetValue(HighLightProperty);
        }
        set
        {
            SetValue(HighLightProperty, value);
        }
    }
}

HighlightedBackgroundColor 但是,从XAML开始,我不知道如何在iOS渲染器中访问它,我拥有的是:

[assembly: ExportRenderer(typeof(BtnRenderer), typeof(BtnRendereriOS))]
namespace BluetoothExample.iOS
{
    public class BtnRendereriOS : ButtonRenderer
    {

        protected override void OnElementChanged(ElementChangedEventArgs<Button> e)
        {
            base.OnElementChanged(e);

            if (Control != null)
            {
                var normalBackgroundColor = Element.BackgroundColor.ToUIColor();
                var _highlightBackgroundColor = Element.HighlightedBackgroundColor.ToUIColor(); //HERE IS MY PROBLEM

            async Task NormalColorState(UIButton button)
            {
                await UIView.TransitionNotifyAsync(button, .25, UIViewAnimationOptions.TransitionCrossDissolve, () =>
                {
                    button.BackgroundColor = normalBackgroundColor;
                });
            }
            Control.TouchDown += async (object sender, EventArgs c) =>
            {
                var button = sender as UIButton;
                await UIView.TransitionNotifyAsync(button, .25, UIViewAnimationOptions.TransitionCrossDissolve, () =>
                {
                    button.BackgroundColor = _highlightBackgroundColor;
                });
            };
        }
    }
}

如何正确访问此属性?