Object of type doesn't match target type 'Xamarin.Forms.ContentView'
<p>I'm using portable Xamarin forms project. I get this error when I debug my page</p>

<p><a href="https://i.stack.imgur.com/wbcUH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/wbcUH.png" alt="enter image description here"></a></p>

<p>xaml :</p>

<pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
   xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
   x:Class="Project1.Views.WebView1"&gt;

  &lt;ContentView.Content&gt;
  &lt;/ContentView.Content&gt;
&lt;/ContentPage&gt;
</code></pre>

<p>xaml.cs :</p>

<pre><code>using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Xamarin.Forms;

namespace Proje1.Views
{
    public partial class WebView1 : ContentPage
    {
        public WebView1()
        {
            InitializeComponent();

            Label header = new Label
            {
                Text = "WebView",
                FontSize = 20,
                FontAttributes = FontAttributes.Bold,
                HorizontalOptions = LayoutOptions.Center
            };
            WebView wView = new WebView
            {
                Source = new UrlWebViewSource
                {
                    Url = "https://www.acikakademi.com",
                },
                VerticalOptions = LayoutOptions.FillAndExpand
            };
            this.Content = new StackLayout
            {
                Children =
                {
                    header,
                    wView
                }
            };
        }        
    }
}
</code></pre>

<p>What should I do to fix this ?</p>