private async Task UpdateVideos()
 {
     try
     {
         message.IsVisible           = false;
         list.IsVisible              = false;
         activityIndicator.IsRunning = true;
         var _videos = new ObservableCollection <YouTubeVideo>((await YouTubeCollectionView.LoadVideosAsync("Xamarin Forms", "relevance", null, 50)).Item2);
         _collectionView  = new XuniCollectionView <YouTubeVideo>(_videos);
         list.ItemsSource = _collectionView;
         list.IsVisible   = true;
     }
     catch
     {
         message.Text      = AppResources.InternetConnectionError;
         message.IsVisible = true;
     }
     finally
     {
         activityIndicator.IsRunning = false;
     }
 }