MvvmCross：从片段中使用自定义MvxAdapter

Question

我正在尝试使用自己的自定义MvxListView向MvxAdapter添加页眉和页脚。

从一个Activity，我可以在OnCreate()方法中将适配器添加到listview，它就可以了。

但如果我尝试从片段中的OnCreateView()尝试相同的操作，我会得到一个Java.Lang.RuntimeException，其中包含以下堆栈跟踪：

at Android.Runtime.JNIEnv.CallNonvirtualVoidMethod (IntPtr jobject, IntPtr jclass, IntPtr jmethod) [0x00000] in <filename unknown>:0 
at Android.Widget.BaseAdapter.NotifyDataSetChanged () [0x00000] in <filename unknown>:0 
at Cirrious.MvvmCross.Binding.Droid.Views.MvxAdapter.NotifyDataSetChanged (System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00000] in <filename unknown>:0 
at Cirrious.MvvmCross.Binding.Droid.Views.MvxAdapter.OnItemsSourceCollectionChanged (System.Object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e) [0x00000] in <filename unknown>:0 
at (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&)
at System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00000] in <filename unknown>:0 
--- End of managed exception stack trace ---
java.lang.NullPointerException
    at android.widget.BaseAdapter.notifyDataSetChanged(BaseAdapter.java:50)
    at mono.java.lang.RunnableImplementor.n_run(Native Method)
    at mono.java.lang.RunnableImplementor.run(RunnableImplementor.java:29)
    at android.os.Handler.handleCallback(Handler.java:615)
    at android.os.Handler.dispatchMessage(Handler.java:92)
    at android.os.Looper.loop(Looper.java:137)
    at android.app.ActivityThread.main(ActivityThread.java:4898)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:511)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)
    at dalvik.system.NativeStart.main(Native Method)

我在这里错过了什么吗？

谢谢！