public MainPageViewModel(INavigationService navigationService)
            : base(navigationService)
        {
            Xamarin.Forms.DependencyService.Register <IBluetoothService>();

            bluetoothService = (DependencyService.Get <IBluetoothService>());
            bluetoothService.Init();


            ShowDeviceNameAlert = new DelegateCommand <string>(alertDeviceName);
            Title = "Main Page";
        }