demo-xf-app-1a/MobileApp1/Views/MainPage.xaml.cs

using MobileApp1.Models;
using System;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;

namespace MobileApp1.Views
{
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class MainPage : FlyoutPage
    {
        public MainPage()
        {
            InitializeComponent();

            flyoutPage.listView.ItemSelected += listView1_OnItemSelected;
        }

        //private void ListView_ItemSelected(object sender, SelectedItemChangedEventArgs e)
        //{
        //    var item = e.SelectedItem as MainPageFlyoutMenuItem;
        //    if (item == null)
        //        return;

        //    var page = (Page)Activator.CreateInstance(item.TargetType);
        //    page.Title = item.Title;

        //    Detail = new NavigationPage(page);
        //    IsPresented = false;

        //    FlyoutPage.ListView.SelectedItem = null;
        //}

        private void listView1_OnItemSelected(object sender, SelectedItemChangedEventArgs e)
        {
            var item = e.SelectedItem as FlyoutPageItem;
            if (item == null)
            {
                return;
            }

            Detail = new NavigationPage((Page)Activator.CreateInstance(item.TargetType));
            flyoutPage.listView.SelectedItem = null;
            IsPresented = false;
        }

    }
}