protected virtual void OnRatingUpdated(RatingUpdatedEventArgs e)
        {
            EventHandler<RatingUpdatedEventArgs> handler = RatingUpdated;

            if (handler != null)
            {
                handler(this, e);
            }
        }
        protected virtual void OnRatingUpdated(RatingUpdatedEventArgs e)
        {
            EventHandler <RatingUpdatedEventArgs> handler = RatingUpdated;

            if (handler != null)
            {
                handler(this, e);
            }
        }
 async void OnRatingUpdated(object sender, RatingUpdatedEventArgs e)
 {
     try
     {
         var currentRating = this.RatingsView.CurrentItem as Rating;
         if (currentRating.SessionId == e.Rating.SessionId)
         {
             var rating = await _sessionService.GetRatingByIdAsync(currentRating.Id);
             currentRating.Rate = rating.Rate;
         }
     }
     catch(Exception ex)
     {
         MessageBox.Show(ex.Message);
     }
 }