问DataTemplate for CompositeCollection不起作用

EN

<Window x:Class="TestCompositeConnection.MainWindow"
        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"
        xmlns:local="clr-namespace:TestCompositeConnection"
        mc:Ignorable="d"
        Title="MainWindow"
        Height="350"
        Width="525">
    <Grid>
        <ListBox Name="myListBox"
                 Height="300"
                 Width="200"
                 Background="White">
            <ListBox.Resources>
                <DataTemplate DataType="x:Type local:MyRectangle">
                    <WrapPanel>
                        <TextBlock Text="{Binding Width}"></TextBlock>
                        <TextBlock Text="{Binding Height}"></TextBlock>
                    </WrapPanel>
                </DataTemplate>
                <DataTemplate DataType="x:Type local:MyLine">
                    <StackPanel>
                        <TextBox Text="{Binding EndX}"></TextBox>
                        <TextBox Text="{Binding EndY}"></TextBox>
                    </StackPanel>
                </DataTemplate>
            </ListBox.Resources>
        </ListBox>
    </Grid>
</Window>

    public partial class MainWindow : Window
    {
        public CompositeCollection Data { get; set; }

        public ObservableCollection<MyRectangle> Rects { get; set; }
        public ObservableCollection<MyLine> Lines { get; set; }

        public MainWindow()
        {
            InitializeComponent();

            Data = new CompositeCollection();

            Rects = new ObservableCollection<MyRectangle>();
            Lines = new ObservableCollection<MyLine>();

            Rects.Add(new MyRectangle
            {
                X = 100,
                Y = 100,
                Width = 100,
                Height = 100
            });

            Lines.Add(new MyLine
            {
                StartX = 200,
                StartY = 3,
                EndX = 300,
                EndY = 100
            });

            Data.Add(new CollectionContainer() { Collection = Rects });
            Data.Add(new CollectionContainer() { Collection = Lines });

            myListBox.ItemsSource = Data;
        }
    }