public BuyerDecisionsViewModel(IMvxMessenger messenger, IUserDefinedCodeService userDefinedCodeService, IDialogService dialogService, IBuyerDecisionsService buyerDecisionsService, IMvxNavigationService navigationService)
        {
            Messenger               = messenger;
            _dialogService          = dialogService;
            _buyerDecisionsService  = buyerDecisionsService;
            _userDefinedCodeService = userDefinedCodeService;
            _navigationService      = navigationService;

            ConfigureValidationRules();
            Validator.ResultChanged += OnValidationResultChanged;
        }
        public AddActivityViewModel(IMvxMessenger messenger, IBuyerDecisionsService buyerDecisionsService, IUserDefinedCodeService userDefinedCodeService, IActivityService activityService, IMvxNavigationService navigationService, IUserService userService)
        {
            Messenger               = messenger;
            _activityService        = activityService;
            _navigationService      = navigationService;
            _userService            = userService;
            _buyerDecisionsService  = buyerDecisionsService;
            _userDefinedCodeService = userDefinedCodeService;

            ConfigureValidationRules();
            Validator.ResultChanged += OnValidationResultChanged;
        }