Can't see bound Items in Listbox.

 using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace DataBinding
{


    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();
            List FL = new List();
            FL.Add(new Friends("Bernard", 20, "Lyon"));
            FL.Add(new Friends("Jean", 34, "Paris"));
            FL.Add(new Friends("Patrick", 29, "Marseille"));
            FL.Add(new Friends("Julie", 56, "Lille"));
            FL.Add(new Friends("Bertrand", 23, "Nice"));

            TestList.ItemsSource = FL;
        }
    }

    public class Friends
    {
        string Name { get; set; }
        int Age { get; set; }
        string Town { get; set; }

        public Friends(string Name, int Age, string Town)
        {
            this.Name = Name;
            this.Age = Age;
            this.Town = Town;
        }
    }
}

     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    d:DesignHeight="300" d:DesignWidth="400" xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk">