title: Xamarin Android FFImageLoading ImageService.Instance.LoadUrl() System.NullReferenceException
body: <p>I've got a strange problem with <strong>FFImageLoading</strong>. Compiler don't show any error, but while application is starting on device, there is thrown an exception:
  <strong>System.NullReferenceException</strong>.</p>
  
  <hr>
  
  <p>Code:</p>
  
  <p><strong>C#</strong></p>
  
  <pre><code>private void setUserImage()
  {
      ImageService.Instance.Initialize();
      imgThunbailUsername = FindViewById&lt;ImageViewAsync&gt;(Resource.Id.imgDisplay);
      string url = @"https://lh4.googleusercontent.com/-Lfgi-xEMwuk/VNWoy8EDWcI/AAAAAAAAACk/rwsluNfhSZY/w1486-h832-no/photo.jpg";
  
      ImageService.Instance.LoadUrl(url)
          .Retry(3, 200)
          .DownSample(60, 60)
          .Into(imgThunbailUsername); // compiler points here with an exception
  }
  </code></pre>
  
  <p><strong>XML</strong></p>
  
  <pre><code>&lt;FFImageLoading.Views.ImageViewAsync
    android:id="@+id/imgDisplay"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:scaleType="fitCenter" /&gt;
  </code></pre>
  
  <hr>
  
  <p>I'd be thankful for any tip, idea, or even another good tool for images in Xamarin.</p>