public EnteringPageViewModel()
        {
            GetCityWeatherCommand = new Command(async() =>
            {
                CurrentWeatherConst.Location = TownName;
                var weatherPageVM            = new CurrentWeatherViewModel(/*TownName*/);
                var weatherPage            = new CurrentWeatherPage();
                weatherPage.BindingContext = weatherPageVM;
                await Application.Current.MainPage.Navigation.PushModalAsync(weatherPage);
            });

            OnClickedBackCommand = new Command(async() =>
            {
                await Application.Current.MainPage.Navigation.PopModalAsync();
            });
        }
        public App()
        {
            InitializeComponent();

            MainPage = new CurrentWeatherPage();
        }