Custom Entry Renderer Problems

CustomEntry.cs

using System;
using Xamarin.Forms;

namespace PROSHIP4GUEST
{
    public class CustomEntry : Entry
    {
        public CustomEntry ()
        {
        }

        public static readonly BindableProperty ImageStartProperty =
            BindableProperty.Create<CustomEntry,ImageSource> (
                p => p.ImageStart, default(ImageSource));

        public ImageSource ImageStart {
            get { return (ImageSource)GetValue (ImageStartProperty); }
            set { SetValue (ImageStartProperty, value); }
        }
    }
}

Using in ContentPage
CustomEntry userCus = new CustomEntry {
ImageStart = ImageSource.FromFile("email.png")
};

CustomEntryRenderer for Android
using System;
using Xamarin.Forms.Platform.Android;
using Xamarin.Forms;
using PROSHIP4GUEST;
using PROSHIP4GUEST.Droid;
using Android.Graphics;
using System.Security.Cryptography;
using System.Threading.Tasks;

[assembly: ExportRendererAttribute(typeof(CustomEntry),typeof(CustomEntryRenderer))]

namespace PROSHIP4GUEST.Droid
{
    public class CustomEntryRenderer : EntryRenderer
    {
        private Bitmap hix;
        public CustomEntryRenderer ()
        {
            this.SetWillNotDraw (false);
            hix = BitmapFactory.DecodeResource (this.Context.Resources, Resource.Drawable.email);
        }


        private static IImageSourceHandler GetHandler(ImageSource source)
        {
            IImageSourceHandler returnValue = null;
            if (source is UriImageSource)
            {
                returnValue = new ImageLoaderSourceHandler();
            }
            else if (source is FileImageSource)
            {
                returnValue = new FileImageSourceHandler();
            }
            else if (source is StreamImageSource)
            {
                returnValue = new StreamImagesourceHandler();
            }
            return returnValue;
        }
        private async Task<Bitmap> GetBitmapAsync(ImageSource source)
        {
            var handler = GetHandler(source);
            var returnValue = (Bitmap)null;
            returnValue = await handler.LoadImageAsync(source, this.Context);
            return returnValue;
        }

        protected override void OnElementChanged (ElementChangedEventArgs<Entry> e)
        {
            base.OnElementChanged (e);
            if (Control != null) {
                Control.SetPadding (40, 0, 0, 0);
            }
        }

        public override async void Draw (Canvas canvas)
        {
            base.Draw (canvas);
            CustomEntry ce = (CustomEntry)this.Element;
            Paint p = new Paint ();

            Bitmap bmp = await GetBitmapAsync(ce.ImageStart);
            canvas.DrawBitmap (hix,0,0,p);

        }

    }
}

But it not working, app stop when i start. How to fix this, thanks.
I want to make Entry like this