android - LinearLayoutManager は getOrientation() を解決できません

Question

フラグメントにRecyclerView実装されており、コードに仕切りを追加しようとしています。RecylcerView意図したとおりに動作していLinearLayoutManagerますが、機能を解決できませんgetOrientation()。

private RecyclerView mRecyclerView;
private RecyclerView.Adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
    View root = (View) inflater.inflate(R.layout.fragment_settings, null);
    getActivity().setTitle("Settings");

    mRecyclerView = (RecyclerView) root.findViewById(R.id.recycler_view_settings);

    mRecyclerView.setHasFixedSize(true);

    mLayoutManager = new LinearLayoutManager(getContext());
    mRecyclerView.setLayoutManager(mLayoutManager);
    mAdapter = new SettingsAdapter(getResources().getStringArray(R.array.setting_list));
    mRecyclerView.setAdapter(mAdapter);
    DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(mRecyclerView.getContext(), mLayoutManager.getOrientation());
    mRecyclerView.addItemDecoration(dividerItemDecoration);
    return root;
}