title: UserDialogs Loading does not show up
body: <p>I am trying to see Loading progress as follows, but it does not show up.</p>
  
  <p><strong>View.cs</strong></p>
  
  <pre><code>ViewModel.SelectedCommand.Execute(null);
  </code></pre>
  
  <p><strong>ViewModel.cs</strong></p>
  
  <pre><code>public ICommand SelectedCommand
  {
      get
      {
         return new MvxAsyncCommand(async () =&gt;
         {
           // the following does not show loading
            using (UserDialogs.Instance.Loading("Loading..."))
            {
               var task = await _classroomService.GetClassRoomAsync(SelectedClassroom.Id);
               ObservableCollection&lt;ClassroomViewModel&gt; class = new ObservableCollection&lt;ClassroomViewModel&gt;(task.ConvertAll(x =&gt; new ClassViewModel(x)));
            }
         });
        }
   }
  </code></pre>
  
  <p><strong>Another example</strong></p>
  
  <pre><code>public ICommand ReloadCommand
  {
      get
      {
        return new MvxAsyncCommand(async () =&gt;
        {
            await RefreshList();
         });
       }
  }
  
  // the following also does not show loading
  private async Task RefreshList()
  {
     using (UserDialogs.Instance.Loading("Loading..."))
     {
         var task = await _classService.GetClasses();
     }
  }
  </code></pre>