切换按钮在Android中不起作用

Question

我正在创建一个应用程序，我需要一个导航抽屉。每件事都很好，但唯一不起作用的是我的切换按钮。

NavigationDrawerFragment.java

public class NavigationDrawerFragment extends Fragment{
private RecyclerView recyclerView;
private static final String PREF_FILE_NAME = "testpref";
public static final String KEY_USER_LEARNED_DRAWER = "user_learned_drawer";
private ActionBarDrawerToggle mDrawerToggle;
private DrawerLayout mDrawerLayout;
private MyProgAdapter adapter;
private View view;
private boolean mUserLearnedDrawer;
private boolean mFromSavedInstanceState;
private NavigationDrawerCallbacks mCallbacks;

Fragment objfragment=null;
public NavigationDrawerFragment() {
    // Required empty public constructor
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mUserLearnedDrawer = Boolean.valueOf(readFromPreferences(getActivity(), KEY_USER_LEARNED_DRAWER, "false"));
    if (savedInstanceState != null) {
        mFromSavedInstanceState = true;
    }
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View layoutview = inflater.inflate(R.layout.fragment_navigation_drawer, container, false);
    recyclerView = (RecyclerView) layoutview.findViewById(R.id.drawerlist);
   adapter = new MyProgAdapter(getActivity(), getData());

    recyclerView.setAdapter(adapter);
    recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
   recyclerView.addOnItemTouchListener(new RecyclerTouchListener(getActivity(), recyclerView, new RecyclerTouchListener.ClickListener() {
        @Override
        public void onClick(View view, int position) {

            selectItem(position);
  Toast.makeText(getActivity(),"OnClick"+position,Toast.LENGTH_SHORT).show();
        }

        @Override
        public void onLongClick(View view, int position) {
            Toast.makeText(getActivity(),"OnLongClick"+position,Toast.LENGTH_SHORT).show();
        }
    }));
    return layoutview;
}
public void selectItem(int position){
    if (mDrawerLayout != null) {
        mDrawerLayout.closeDrawer(Gravity.START);
    }
    if (mCallbacks != null) {
        mCallbacks.onNavigationDrawerItemSelected(position);
    }

}

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    try {
        mCallbacks = (NavigationDrawerCallbacks) activity;
    } catch (ClassCastException e) {
        throw new ClassCastException("Activity must implement NavigationDrawerCallbacks.");
    }
}

@Override
public void onDetach() {
    super.onDetach();
    mCallbacks = null;
}

public static List<Information> getData() {
    List<Information> data = new ArrayList<>();
    int[] icons = {R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher,R.mipmap.ic_launcher};
    String[] titles = {"ABC", "XYZ", "MNO", "PQR", "About us"};
    for (int i = 0; i < icons.length && i < titles.length; i++) {
        Information current = new Information();
        current.iconId = icons[i];
        current.title = titles[i];
        data.add(current);
    }
    return data;
}

public void setUp(int fragmentId, DrawerLayout drawerLayout, final Toolbar toolbar) {
    view = getActivity().findViewById(fragmentId);

    mDrawerLayout = drawerLayout;
    mDrawerToggle = new ActionBarDrawerToggle(getActivity(), drawerLayout, toolbar, R.string.drawer_open, R.string.drawer_close) {

        @Override
        public void onDrawerOpened(View drawerView) {
            super.onDrawerOpened(drawerView);
            if (!mUserLearnedDrawer) {
                mUserLearnedDrawer = true;
                savedToPreferences(getActivity(), KEY_USER_LEARNED_DRAWER, mUserLearnedDrawer + "");


            }

            getActivity().invalidateOptionsMenu();
        }

        @Override
        public void onDrawerClosed(View drawerView) {
            super.onDrawerClosed(drawerView);
            getActivity().invalidateOptionsMenu();
        }

        @Override
        public void onDrawerSlide(View drawerView, float slideOffset) {
            if (slideOffset < 0.6) {
                toolbar.setAlpha(1 - slideOffset);
            }
        }
    };
    if (!mUserLearnedDrawer && !mFromSavedInstanceState) {
        mDrawerLayout.openDrawer(view);
    }

    mDrawerLayout.setDrawerListener(mDrawerToggle);
    mDrawerLayout.post(new Runnable() {
        @Override
        public void run() {
            mDrawerToggle.syncState();
        }
    });

}

public static void savedToPreferences(Context context, String preferencename, String preferenceValue) {
    SharedPreferences sharedPreference = context.getSharedPreferences(PREF_FILE_NAME, Context.MODE_PRIVATE);
    SharedPreferences.Editor editor = sharedPreference.edit();
    editor.putString(preferencename, preferenceValue);
    editor.apply();
}

public static String readFromPreferences(Context context, String preferencename, String defaultValue) {
    SharedPreferences sharedPreference = context.getSharedPreferences(PREF_FILE_NAME, Context.MODE_PRIVATE);
    return sharedPreference.getString(preferencename, defaultValue);

}

public static interface NavigationDrawerCallbacks {
    /**
     * Called when an item in the navigation drawer is selected.
     */
    void onNavigationDrawerItemSelected(int position);
} }

MainActivity.java

public class MainActivity extends ActionBarActivity implements NavigationDrawerFragment.NavigationDrawerCallbacks {
private Toolbar toolbar;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    toolbar = (Toolbar) findViewById(R.id.app_bar);
    setSupportActionBar(toolbar);
    getSupportActionBar().setDisplayShowHomeEnabled(true);

    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionBar().setHomeButtonEnabled(true);

    NavigationDrawerFragment navigationDrawerFragment =
            (NavigationDrawerFragment) getSupportFragmentManager()
                    .findFragmentById(R.id.fragment_navigation_drawer);
    navigationDrawerFragment.setUp(R.id.fragment_navigation_drawer, (DrawerLayout) findViewById(R.id.drawer_layout), toolbar);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {

    int id = item.getItemId();

if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

@Override
public void onNavigationDrawerItemSelected(int position) {
    Fragment objfragment = null;
    Intent intent = null;
    switch (position) {
        case 0:
            objfragment=new ABC();

            break;
        case 1:
            objfragment=new XYZ();

            break;
        case 2:objfragment=new MNO();
                           break;
        case 3:
            break;
        default:
            break;
    }

        FragmentManager fragmentManager = getSupportFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.container, objfragment)
                .commit();

}}

我之前使用过此代码并且可以正常使用，但这次它还没有工作。 请帮忙