My custom WebView. It has a HTML string property. This was very useful to draw my chart :) a simple HTML file with some embedded Javascript to draw the shapes. It was the faster way for me to make a cross pie chart control. When the HTML property has changed, the source of the WebView gets updated.

//–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
// <copyright file=“ExtWebView.cs“ company=“Krossapp“>
//     Copyright (c) Krossapp. All rights reserved.
// </copyright>
// <author>Nicolas Krier</author>
//–––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
namespace SDF.XForm.Controls
{
    #region Using

    using System.Diagnostics.CodeAnalysis;
    using System.Windows.Input;
    using Xamarin.Forms;

    #endregion

    /// <summary>
    /// Web view.
    /// </summary>
    public class ExtWebView : WebView
    {
        #region Bindable property

        /// <summary>
        /// The html property.
        /// </summary>
        [SuppressMessage(“StyleCop.CSharp.MaintainabilityRules“, “SA1401:FieldsMustBePrivate“, Justification = “Reviewed.“)]
        public static BindableProperty HtmlProperty = BindableProperty.Create<ExtWebView, string>(x => x.Html, null, BindingMode.OneWay, propertyChanged: WhenHtmlChanged);

        /// <summary>
        /// The command clicked property.
        /// </summary>
        [SuppressMessage(“StyleCop.CSharp.MaintainabilityRules“, “SA1401:FieldsMustBePrivate“, Justification = “Reviewed.“)]
        public static BindableProperty Command = BindableProperty.Create<ExtWebView, ICommand>(x => x.CommandClicked, null);

        #endregion

        #region Constructor

        /// <summary>
        /// Initializes a new instance of the <see cref=“ExtWebView“/> class.
        /// </summary>
        public ExtWebView()
            : base()
        {
            this.HandleTapEvent();
        }

        #endregion

        #region Property

        /// <summary>
        /// Gets or sets the html.
        /// </summary>
        /// <value>The html.</value>
        public string Html
        {
            get { return (string)this.GetValue(HtmlProperty); }
            set { this.SetValue(HtmlProperty, value); }
        }

        /// <summary>
        /// Gets or sets the command clicked.
        /// </summary>
        /// <value>The command clicked.</value>
        public ICommand CommandClicked
        {
            get { return (ICommand)this.GetValue(Command); }
            set { this.SetValue(Command, value); }
        }

        #endregion

        /// <summary>
        /// Raises the html changed event.
        /// </summary>
        /// <param name=“sender“>The sender.</param>
        /// <param name=“oldValue“>Old value.</param>
        /// <param name=“newValue“>New value.</param>
        private static void WhenHtmlChanged(BindableObject sender, string oldValue, string newValue)
        {
            WebView ctrl = (WebView)sender;
            ctrl.Source = new HtmlWebViewSource() { Html = newValue };
        }

        /// <summary>
        /// Handle the tap event : the click.
        /// </summary>
        private void HandleTapEvent()
        {
            /*
            var tapGestureRecognizer = new TapGestureRecognizer();
            tapGestureRecognizer.Tapped += (sender, args) =>
            {
                if (args != null && this.CommandClicked != null && this.CommandClicked.CanExecute(args))
                {
                    this.CommandClicked.Execute(args);
                }
            };
            this.GestureRecognizers.Add(tapGestureRecognizer);
            */
        }
    }
}