在自定义控件中没有来自Rectangle对象的事件

嗨 我尝试使用2D对象制作自定义控件.问题是我没有从2D对象获得事件.当我将以下代码中的Rectangle替换为Button时，将发送事件.
我忘记了什么?
非常感谢！
文件RectangleButton.cs:

Hy I try to make a Custom Control with 2D Objects. The Problem is, that i didn’t get events form 2D Object. When i replace Rectangle in the following code with a Button, the event will be sent.
What does i forgot?
Many Thanks!
File RectangleButton.cs:

public class RectangleButton : Control
    {
        private Rectangle _buttonWrite;
        static RectangleButton()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(RectangleButton), new FrameworkPropertyMetadata(typeof(RectangleButton)));
        }
        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();
            _buttonWrite = new Rectangle();
            _buttonWrite = this.GetTemplateChild("myRectangle") as Rectangle;
            _buttonWrite.AddHandler(Rectangle.MouseDownEvent, new MouseButtonEventHandler(ButtonWrite_MouseLeftButtonDown), true);
        }
        void ButtonWrite_MouseLeftButtonDown(object sender, MouseEventArgs e)
        {            
            MessageBox.Show("MouseLeftButtonDown Event!!");
        }
    }

Generic.xaml文件:

<resourcedictionary>
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:RectangleEvent">
    <Style TargetType="{x:Type local:RectangleButton}">
        <setter property="Template">
            <setter.value>
                <controltemplate targettype="{x:Type local:RectangleButton}">
                    <border removed="{TemplateBinding Background}">
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}">
                        <grid>
                            <rectangle x:name="myRectangle" xmlns:x="#unknown" />
                        </grid>                        
                    </border>
                </controltemplate>
            </setter.value>
        </setter>
    </Style>
</resourcedictionary>

MainWindow.xaml文件:

<window x:class="RectangleEvent.MainWindow" xmlns:x="#unknown">
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525" xmlns:my="clr-namespace:RectangleEvent">
    <grid>
        <my:rectanglebutton horizontalalignment="Left" x:name="rectangleButton1" verticalalignment="Top" height="141" width="162" removed="#FFF81010" xmlns:my="#unknown" />
    </grid>
</window>