Xamarin MvvmCross Fragment类强制转换异常

Question

我试图弄清楚要为此类强制转换例程做些什么。我直接关注斯图尔特的例子，我似乎被困在这里。任何帮助将不胜感激。

Android.Views.InflateException：类型＆＃39; Android.Views.InflateException＆＃39;的异常被扔了。

  

java.lang.ClassCastException：   md5d958475ca14cd4931af92c1266ed3aa8.DrawerFragment无法强制转换为   android.app.Fragment

DrawerFragment扩展了MvxFragment

var drawerFragment = (DrawerFragment)this.SupportFragmentManager.FindFragmentById(Resource.Id.drawer_fragment);

在.axml中添加片段：

   <?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:local="http://schemas.android.com/apk/res-auto"
    android:id="@+id/myDrawer"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
<!-- Main Content View-->
    <FrameLayout
        android:id="@+id/content_frame"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
      <fragment
        class="Sample.Android.Views.DrawerFragment"
        android:id="@+id/drawer_fragment"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />
    </FrameLayout>
<!-- The navigation drawer Layout -->
    <Mvx.MvxListView
        android:id="@+id/leftListView"
        android:layout_width="240dp"
        android:layout_height="match_parent"
        android:layout_gravity="left"
        android:choiceMode="singleChoice"
        android:divider="#D2D2D2"
        android:dividerHeight="2dp"
        android:background="#F2F2F2"
        local:MvxBind="ItemsSource DrawerItems"
        local:MvxItemTemplate="@layout/simple_list_item" />
</android.support.v4.widget.DrawerLayout>