无法使用LoaderManager查看ListFragment中的联系人列表

Question

我正在尝试制作联系人列表视图片段。这是代码：

public class ContactsListFragment extends RoboListFragment implements
        LoaderManager.LoaderCallbacks<Cursor> {

    private static final int CONTACTS_LIST_LOADER = 0x01;
    CursorAdapter adapter;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Log.d("onCreate", "called");

        String[] fromColumns = {ContactsContract.Contacts._ID,
                            ContactsContract.Contacts.DISPLAY_NAME,
                            ContactsContract.CommonDataKinds.Email.ADDRESS};

        int[] toViews = {   R.id.contact_list_item_id,
                            R.id.contact_list_item_name,
                            R.id.contact_list_item_email};

        getLoaderManager().initLoader(CONTACTS_LIST_LOADER, null, this);
        adapter = new SimpleCursorAdapter(
                getActivity().getApplicationContext(), R.layout.contacts_list_item,
                null, fromColumns, toViews,
                CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
        setListAdapter(adapter);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        Log.d("onCreateView", "called");
        View rootView = inflater.inflate(R.layout.contacts_list_fragment, container, false);
        return rootView;
    }

    @Override
    public Loader<Cursor> onCreateLoader(int id, Bundle args) {
        Log.d("onCreateLoader", "called");
        return new CursorLoader(getActivity(),
            ContactsContract.CommonDataKinds.Email.CONTENT_URI, null, null, null, null);
    }
    @Override
    public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {
        Log.d("onLoadFinished", "called");
        adapter.swapCursor(cursor);
    }
    @Override
    public void onLoaderReset(Loader<Cursor> loader) {
        Log.d("onLoaderReset", "called");
        adapter.swapCursor(null);
    }
}

但是虽然打印了所有日志，并且没有例外，但我在屏幕上看不到任何内容。

片段布局：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context="com.example.Fragments.ContactsListFragment">

    <ListView
        android:id="@id/android:list"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />
    <TextView
        android:visibility="gone"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:text="@string/contact_list_empty"/>

</RelativeLayout>

列表项布局：

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/contact_list_item_id"/>
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/contact_list_item_name"
        android:layout_below="@id/contact_list_item_id"/>
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/contact_list_item_email"
        android:layout_below="@id/contact_list_item_name"/>
</RelativeLayout>

我在这里有点不知所措。我的父活动包括片段：

<fragment
    android:id="@+id/contact_list_fragment"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:name="com.example.Fragments.ContactsListFragment"
    tools:layout="@layout/contacts_list_fragment"
    android:layout_below="@id/fakeView"/>