Round Corner Gridlayout Xamarin Android

Question

I want to Create RoundCorner GridLayout.I have added round corner to Gridlayot Control in Xamarin but Gridlayout BackgroundColor display in Back Side like this.Please help me to resolve issue. GridLayout after Drawable Add

Xamarin.Forms Xaml Code :

xmlns:local="clr-namespace:XamainControl.Renderer;assembly=XamainKcsControl"
<Grid BackgroundColor="Purple" WidthRequest="300">
         <Grid.RowDefinitions>
  <RowDefinition Height="Auto"/>      
</Grid.RowDefinitions>
<local:KcsGrid Grid.Row="0"
               BorderColor="Blue"
               BackgroundColor="Yellow"
               BorderRadius="20"
               BorderWidth="10" Padding="15" >
  <Label Text="Customization Page"
         FontSize="25"
         TextColor="Red"
         VerticalOptions="CenterAndExpand"
         HorizontalOptions="CenterAndExpand"/>
</local:KcsGrid>
</Grid>

Custom Grid Property Create Xamarin.Forms

 public class KcsGrid : Grid
{
    #region Constructor
    public KcsGrid() : base()
    {
        this.Margin = new Thickness(0, 0, 0, -6);
    }
    #endregion

    #region Properties   

    public static BindableProperty BorderColorProperty = BindableProperty.Create<KcsGrid, Color>(o => o.BorderColor, Color.Transparent);

    public Color BorderColor
    {
        get { return (Color)GetValue(BorderColorProperty); }
        set { SetValue(BorderColorProperty, value); }
    }

    public static BindableProperty BorderWidthProperty = BindableProperty.Create<KcsGrid, float>(o => o.BorderWidth, 0);

    public float BorderWidth
    {
        get { return (float)GetValue(BorderWidthProperty); }
        set { SetValue(BorderWidthProperty, value); }
    }

    public static BindableProperty BorderRadiusProperty = BindableProperty.Create<KcsGrid, float>(o => o.BorderRadius, 0);

    public float BorderRadius
    {
        get { return (float)GetValue(BorderRadiusProperty); }
        set { SetValue(BorderRadiusProperty, value); }
    }


    public static BindableProperty WidthValueProperty = BindableProperty.Create<KcsGrid, int>(o => o.WidthValue,100);

    public int WidthValue
    {
        get { return (int)GetValue(WidthValueProperty); }
        set { SetValue(WidthValueProperty, value); }
    }

    public static BindableProperty HeightValueProperty = BindableProperty.Create<KcsGrid, int>(o => o.HeightValue,50);

    public int HeightValue
    {
        get { return (int)GetValue(HeightValueProperty); }
        set { SetValue(HeightValueProperty, value); }
    }

    #endregion
}

Xamarin.Android Code :

namespace XamainKcsControl.Droid.Renderer {

public class CustomGridRender : ViewRenderer<KcsGrid,GridLayout>
{
    private BorderRenderer _renderer;
    GridLayout Cusgd;
    protected override void OnElementChanged(ElementChangedEventArgs<KcsGrid> e)
    {
        base.OnElementChanged(e);
        if (e.OldElement != null || this.Element == null)
            return;                                     
        Cusgd = new GridLayout(Context);
        if (Control == null)
        {              
            var curgd = Element as KcsGrid;
            SetNativeControl(Cusgd);
            UpdateBackground(curgd);
            //UpdateMeasurelayout(curgd);
        }                               
    }    

    protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
    {
        base.OnElementPropertyChanged(sender, e);
        if (Element == null)
            return;
        var Gd = Element as KcsGrid;

        if (e.PropertyName == KcsGrid.BorderColorProperty.PropertyName || e.PropertyName == KcsGrid.BorderWidthProperty.PropertyName || e.PropertyName == KcsGrid.BorderRadiusProperty.PropertyName)
        {
            UpdateBackground(Gd);
        }

        if (e.PropertyName == KcsGrid.WidthValueProperty.PropertyName || e.PropertyName == KcsGrid.HeightValueProperty.PropertyName)
        {
            UpdateMeasurelayout(Gd);
        }
        //SetNativeControl(Cusgd);
    }

    void UpdateMeasurelayout(KcsGrid Gd)
    {
        GridLayout.LayoutParams Gdparm = new GridLayout.LayoutParams();
        Gdparm.Width = (int)Forms.Context.ToPixels(Gd.WidthValue);
        Gdparm.Height = (int)Forms.Context.ToPixels(Gd.HeightValue);            
        Cusgd.LayoutParameters = Gdparm;
        //SetNativeControl(Cusgd);            
    }

    void UpdateBackground(KcsGrid Gd)
    {
        if (_renderer != null)
        {
            _renderer.Dispose();
            _renderer = null;
        }
        _renderer = new BorderRenderer();
        Cusgd.Background = _renderer.GetBorderBackground(Gd.BorderColor,Gd.BackgroundColor, Gd.BorderWidth, Gd.BorderRadius);            
    }
}

}

Gradient Drawable

  public Drawable GetBorderBackground(Color borderColor, Color backgroundColor, float borderWidth, float borderRadius)
    {
        if (_background != null)
        {
            _background.Dispose();
            _background = null;
        }
        borderWidth = borderWidth > 0 ? borderWidth : 0;
        borderRadius = borderRadius > 0 ? borderRadius : 0;
        borderColor = borderColor != Color.Default ? borderColor : Color.Transparent;
        backgroundColor = backgroundColor != Color.Default ? backgroundColor : Color.Transparent;

        var strokeWidth = Xamarin.Forms.Forms.Context.ToPixels(borderWidth);
        var radius = Xamarin.Forms.Forms.Context.ToPixels(borderRadius);
        _background = new GradientDrawable();
        _background.SetColor(backgroundColor.ToAndroid());
        if (radius > 0)
            _background.SetCornerRadius(radius);
        if (borderColor != Color.Transparent && strokeWidth > 0)
        {
            _background.SetStroke((int)strokeWidth, borderColor.ToAndroid());
        }

        return _background;
    }