public NavigationService(NavigationDataBag navigationDataBag, INavigationRouteService navigationRouteService, MvvmApp mvvmApp)
        {
            this.navigationDataBag      = navigationDataBag;
            this.navigationRouteService = navigationRouteService;
            this.mvvmApp = mvvmApp;
            this.mvvmApp.FormsApplication.PropertyChanged += FormsApplication_PropertyChanged;

            if (this.mvvmApp.FormsApplication.MainPage != null)
            {
                this.OnMainPageChanged();
            }
        }
        public void Configure(MvvmApp mvvmApp, INavigationRouteService navigationRouteService)
        {
            navigationRouteService.RegisterRoute(nameof(Details1Page), typeof(Details1Page));

            mvvmApp.FormsApplication.MainPage = new AppShell();
        }