public ChangeWorkerDialogViewModel(RequestServiceImpl.RequestService requestService, int requestId)
        {
            _requestService = requestService;
            _requestId      = requestId;
            WorkerList      = new ObservableCollection <WorkerDto>();
            WorkerList.Add(new WorkerDto()
            {
                Id      = -1,
                SurName = "Нет мастера"
            });
            foreach (var master in _requestService.GetMasters(null))
            {
                WorkerList.Add(master);
            }
            var request = _requestService.GetRequest(_requestId);

            _oldMasterId   = request.MasterId;
            SelectedWorker = WorkerList.SingleOrDefault(w => w.Id == (request.MasterId ?? -1));
            Refresh(null);
        }