async void PostCommentClick(object sender, EventArgs args) { if (Constantes.authModel != null && Constantes.authModel.Connected) { bool succeed = await CommentsModel.PostComment(comment.Text, placeID); if (succeed) { DependencyService.Get <IMessage>().ShortAlert("Thanks for your comment !"); Place p = CommentsModel.GetPlaceWithComments(placeID); BindingContext = new PlaceDetailsViewModel { BindedPlace = p }; ListComments.ItemsSource = p.comments; } else { DependencyService.Get <IMessage>().ShortAlert("An error occured while posting your comment. Please try again later."); } } else { DependencyService.Get <IMessage>().ShortAlert("You must be logged to comment."); } comment.Text = ""; }