怎么为HierarchicalDataTemplate模板生成的控件添加事件

如何为HierarchicalDataTemplate模板生成的控件添加事件？
一般的模板直接就能在模板中的控件属性中设置，可是HierarchicalDataTemplate直接生成了TreeViewItem（ListBoxItem也是一样），没地方设置啊

XML code

<Window x:Class="WpfApplication3.MainWindow"        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"        xmlns:src="clr-namespace:WpfApplication3"        Title="MainWindow" Height="350" Width="525">    <Grid>        <TreeView x:Name="Tree" ItemsSource="{Binding}">            <TreeView.Resources>                <DataTemplate x:Key="aTemplate" DataType="{x:Type src:AB}">                    <TextBox Text="{Binding Path=abc}" />                </DataTemplate>            </TreeView.Resources>            <TreeView.ItemTemplate>                <HierarchicalDataTemplate DataType="{x:Type src:A}"                                               ItemsSource="{Binding Path=ab}"                                              ItemTemplate="{StaticResource aTemplate}">                    <TextBox x:Name="NameBox" Width="160" Text="{Binding Path=name}"                             LostFocus="textBox_LostFocus" />                </HierarchicalDataTemplate>            </TreeView.ItemTemplate>        </TreeView>    </Grid></Window>

C# code

using System;using System.Collections.Generic;using System.Collections.ObjectModel;using System.Linq;using System.Text;using System.Windows;using System.Windows.Controls;using System.Windows.Data;using System.Windows.Documents;using System.Windows.Input;using System.Windows.Media;using System.Windows.Media.Imaging;using System.Windows.Navigation;using System.Windows.Shapes;namespace WpfApplication3{    /// <summary>    /// Interaction logic for MainWindow.xaml    /// </summary>    public partial class MainWindow : Window    {        public MainWindow()        {            InitializeComponent();            ObservableCollection<A> a = new ObservableCollection<A>();            a.Add(new A());            a[0].name = "thy";            ObservableCollection<AB> ab = new ObservableCollection<AB>();            ab.Add(new AB());            ab[0].abc = "38";            a[0].ab = ab;            Tree.DataContext = a;        }    }    class A    {        public string name { get; set; }        public ObservableCollection<AB> ab { get; set; }    }    class AB    {        public string abc { get; set; }    }}