public MainViewModel(ITwitterFeedService twitterFeedService, INavigationService navigationService, ICommentsService commentsService)
        {
            _twitterFeedService = twitterFeedService;
            _navigationService = navigationService;
            _commentsService = commentsService;

            Tweets = new ObservableCollection<TweetDto>();
        }
 public CommentsService(ITweetsDataContextFactory contextFactory, ITwitterFeedService twitterFeedService)
 {
     _contextFactory = contextFactory;
     _twitterFeedService = twitterFeedService;
 }