当父级滚动时隐藏浮动操作按钮

我正在创建一个自定义 FAB 两个按钮 android 和 iOS 平台使用 Xamarin.Forms .

一切都很好,但现在我想以某种方式得到 scrolled 最近父级的事件 绝妙的 如果有的话,我可以隐藏 绝妙的 当用户滚动时按钮,然后在滚动完成2秒后再次显示?.

父级可以是普通的 ScrollView 或者它可能是一个 ListView .
这可以通过每个平台的相同自定义渲染器实现吗?或者,这甚至可以实现吗?

这就是我迄今为止所做的:

1. FabButton 班级:

public partial class FabButton : Button
{
    public static BindableProperty ButtonColorProperty = BindableProperty.Create(nameof(ButtonColor), typeof(Color), typeof(FabButton), Color.Accent);
    public Color ButtonColor
    {
        get => (Color)GetValue(ButtonColorProperty);
        set => SetValue(ButtonColorProperty, value);
    }
    public FabButton()
    {
        InitializeComponent();
    }
}

2. 网间网操作系统 自定义呈现程序:
   

   public class FabButtonRenderer:ButtonRenderer
   {
       protected override void OnElementChanged(ElementChangedEventArgs<Button> e)
       {
           base.OnElementChanged(e);
           if(e.NewElement == null)
               return;
           if (Element.WidthRequest <= 0)
               Element.WidthRequest = 60;
           if (Element.HeightRequest <= 0)
               Element.HeightRequest = 60;
           if (Element.Margin == new Thickness(0, 0, 0, 0))
               Element.Margin = new Thickness(0, 0, 20, 20);
           Element.CornerRadius = (int) Element.WidthRequest / 2;
           Element.BorderWidth = 0;
           Element.Text = null;
           Control.BackgroundColor = ((FabButton) Element).ButtonColor.ToUIColor();
       }
       public override void Draw(CGRect rect)
       {
           base.Draw(rect);
           Layer.ShadowRadius = 0.2f;
           Layer.ShadowColor = UIColor.Black.CGColor;
           Layer.ShadowOffset = new CGSize(1, 1);
           Layer.ShadowOpacity = 0.80f;
           Layer.ShadowPath = UIBezierPath.FromOval(Layer.Bounds).CGPath;
           Layer.MasksToBounds = false;
       }
       protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
       {
           base.OnElementPropertyChanged(sender, e);
           if (e.PropertyName == nameof(FabButton.ButtonColor))
               Control.BackgroundColor = ((FabButton) Element).ButtonColor.ToUIColor();
       }
   }
   

3. 安卓 自定义呈现程序:

   public class FabButtonRenderer: Xamarin.Forms.Platform.Android.AppCompat.ViewRenderer<FabButton,FloatingActionButton>
   {
       public static void InitRenderer() { }
       public FabButtonRenderer(Context context):base(context)
       {
   
       }
   
       protected override void OnElementChanged(ElementChangedEventArgs<FabButton> e)
       {
           base.OnElementChanged(e);
           if (e.NewElement == null)
               return;
           if (e.NewElement.HeightRequest <= 0)
               e.NewElement.HeightRequest = 85;
           if (e.NewElement.WidthRequest <= 0)
               e.NewElement.WidthRequest = 75;
           if (e.NewElement.Margin.Equals(new Thickness(0, 0, 0, 0)))
               e.NewElement.Margin = new Thickness(0, 0, 5, 10);
           var fabButton = new FloatingActionButton(Context);
           ViewCompat.SetBackgroundTintList(fabButton, ColorStateList.ValueOf(Element.ButtonColor.ToAndroid()));
           fabButton.UseCompatPadding = true;
           if (!string.IsNullOrEmpty(Element.Image?.File))
               fabButton.SetImageDrawable(Context.GetDrawable(Element.Image.File));
           fabButton.Click += FabButton_Clicked;
           SetNativeControl(fabButton);
       }
   
       protected override void OnLayout(bool changed, int l, int t, int r, int b)
       {
           base.OnLayout(changed, l, t, r, b);
           Control.BringToFront();
       }
   
       protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
       {
           if (e.PropertyName == nameof(Element.ButtonColor))
               ViewCompat.SetBackgroundTintList(Control, ColorStateList.ValueOf(Element.ButtonColor.ToAndroid()));
           if (e.PropertyName == nameof(Element.Image))
           {
               if (!string.IsNullOrEmpty(Element.Image?.File))
                   Control.SetImageDrawable(Context.GetDrawable(Element.Image.File));
           }
           base.OnElementPropertyChanged(sender, e);
       }
   
       public void FabButton_Clicked(object sender, EventArgs e)
       {
           Element.SendClicked();
       }
   }