internal NumberEntitiesVM(
            IEnumerable <NumberEntitiy> numberEntities,
            NumbersHubClient numbersHubClient)
        {
            Debug.Assert(numberEntities != null);

            _numbersHubClient = numbersHubClient;
            _numbersHubClient.NumberCreated += OnNumberCreated;
            _numbersHubClient.NumberDeleted += OnNumberDeleted;

            CreateCommand = new DelegateCommand(Create);

            foreach (var numberEntitiy in numberEntities)
            {
                var numberEntityVM = new NumberEntityVM(numberEntitiy, _numbersHubClient);
                NumberEntitiyVMs.Add(numberEntityVM);
            }
        }
        private void OnNumberCreated(NumberEntitiy numberEntitiy)
        {
            var numberEntityVM = new NumberEntityVM(numberEntitiy, _numbersHubClient);

            NumberEntitiyVMs.Add(numberEntityVM);
        }