private async Task SelectAsync()
        {
            var page = new RaceResultsPage();

            var vm = new MarathonResultsPageViewModel(this.Navigation, this.Race);

            page.BindingContext = vm;

            await this.Navigation.PushAsync(page);

            await vm.GetResultsAsync();
        }
        private async void ListView_ItemSelected(object sender, SelectedItemChangedEventArgs e)
        {
            Race selectedRace;

            selectedRace = (Race)e.SelectedItem;

            RaceResultsPage resultsPage = new RaceResultsPage();

            resultsPage.TheRace = selectedRace;

            await Navigation.PushAsync(resultsPage);

            // code here now executes after the resultsPage is navigated to
        }