public MainViewModel(INetworkService networkService, ICurrencyService currencyService) 
        {
            this.money = new Money() { Rate = 0.8440 };

            this.networkService = networkService;
            this.currencyService = currencyService;
            
            this.convertCommand = new DelegateCommand(ConvertExecute, CanConvertExecute);
            this.rateCommand = new DelegateCommandAsync(RateExecute);
        }
 public override async Task OnNavigatedTo(NavigationEventArgs args)
 {
     this.To = "- €";
     if (networkService.IsOnline())
     {
         var response = await this.currencyService.GetPoundCurrencyAsync();
         this.money = JsonConvert.DeserializeObject<Money>(response);
         GoogleAnalytics.EasyTracker.GetTracker().SendView("MainPage");
     }
 }