public MainPageViewModel(IiBeaconEventTriggerService ibeaconEventTriggerService,
                                 IPageDialogService pageDialogService)
        {
            _ibeaconEventTriggerService = ibeaconEventTriggerService;
            _pageDialogService          = pageDialogService;

            _ibeaconEventTriggerService.PropertyChanged += servicePropertyChanged;

            AddEventCommand      = new DelegateCommand(addEvent);
            ClearAllEventCommand = new DelegateCommand(clearAllEvent);
            StartScanCommand     = new DelegateCommand(startScan);
            StopScanCommand      = new DelegateCommand(stopScan);
        }