public MethodMainViewModel(IEventAggregator aggregator, IDataService <LabDbEntities> labDbData, ISpecificationService specificationService) : base() { _labDbData = labDbData; _eventAggregator = aggregator; _specificationService = specificationService; DeleteMethodCommand = new DelegateCommand( () => { _selectedMethod.Delete(); }, () => IsSpecAdmin && _selectedMethod != null); NewMethodCommand = new DelegateCommand( () => { _specificationService.CreateMethod(); }, () => IsSpecAdmin); _eventAggregator.GetEvent <MethodChanged>().Subscribe( tkn => RaisePropertyChanged("MethodList")); }