title: Xamarin ExportRenderer could not be found
body: <p>I'm trying to create a custom renderer for an advert</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Text;
  using Xamarin.Forms;
  using Xamarin.Forms.PlatformConfiguration.AndroidSpecific;
  using FreeFallCalculator.Controls;
  using FreeFallCalculator.Models;
  using Xamarin.Forms.Internals;
  
  [assembly: ExportRenderer(typeof(AdControlView), typeof(AdViewRenderer))]
  namespace FreeFallCalculator.Models
  {
      class AdViewRenderer
      {
  
      }
  }
  </code></pre>
  
  <p>It keeps giving me this error when trying to compile:</p>
  
  <blockquote>
    <p>Severity   Code    Description Project File    Line    Suppression State
    Error   CS0246  The type or namespace name 'ExportRendererAttribute' could not be found (are you missing a using directive or an assembly reference?)           </p>
  </blockquote>