几次点击bottomNavigation后，某个fragment的View不再显示

主要活动：

问题是在三个fragment中的几次transition之后（大约3个transition之后），fragment的view一直在后台，也就是没有变化，应用没有crash，内存没有增长（used,check in the工作室）。

使用 cicerone 在碎片中移动

@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
    switch (item.getItemId()){
        case R.id.certificationItem:
            router.replaceScreen(FragmentScreenKeys.FRAGMENT_CERTIFICATION);
            return true;
        case R.id.planItem:
            router.replaceScreen(FragmentScreenKeys.FRAGMENT_PLAN);
            return true;
        case R.id.chatItem:
            router.replaceScreen(FragmentScreenKeys.FRAGMENT_CHAT);
            return true;
            default:
                throw new RuntimeException("Unknown item.getId");
    }
}

片段1：

private View view;

@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ((MainActivity)getActivity()).getComponent().inject(this);
}

@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    view = inflater.inflate(R.layout.fragment_certification, container, false);
    return view;
}

@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    ButterKnife.bind(this, view);
}

@Override
public void onResume() {
    super.onResume();
    holder.setNavigator(navigator);
}

@Override
public void onPause() {
    holder.removeNavigator();
    super.onPause();
}

@Override
public void onDestroyView() {
    super.onDestroyView();
    view = null;
}

@Override
public Fragment newInstance() {
    return new FragmentCertification();
}

片段2：

private View view;
private LearningAdapter adapter;

@Inject
ApiService apiService;

@BindView(R.id.recyclerPlan) RecyclerView recyclerPlan;

@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ((MainActivity)getActivity()).getComponent().inject(this);
}

@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    view = inflater.inflate(R.layout.fragment_plan, container, false);
    return view;
}

@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
    ButterKnife.bind(this, view);
    initRecycler(view);
}

@Override
public void onResume() {
    super.onResume();
    showLearning();
}

private void initRecycler(View view){
    recyclerPlan.setLayoutManager(new LinearLayoutManager(view.getContext(),
            OrientationHelper.VERTICAL, false));
}

private void showLearning(){
    adapter = new LearningAdapter(new ArrayList<>());
    recyclerPlan.setAdapter(adapter);
    adapter.notifyDataSetChanged();
}

@Override
public void onDestroyView() {
    super.onDestroyView();
    view = null;
}

@Override
public Fragment newInstance() {
    return new FragmentPlan();
}

片段3：

private View view;

@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    view = inflater.inflate(R.layout.fragment_chat, container, false);
    return view;
}

@Override
public void onDestroyView() {
    super.onDestroyView();
    view = null;
}

@Override
public Fragment newInstance() {
    return new FragmentChat();
}

和导航器：

public MainNavigator(FragmentActivity activity, int containerId) {
    super(activity, containerId);
}

@Override
protected Intent createActivityIntent(Context context, String screenKey, Object data) {
    return null;
}

@Override
protected Fragment createFragment(String screenKey, Object data) {
    switch (screenKey){
        case FragmentScreenKeys.FRAGMENT_CERTIFICATION:
            return new FragmentCertification().newInstance();
        case FragmentScreenKeys.FRAGMENT_PLAN:
            return new FragmentPlan().newInstance();
        case FragmentScreenKeys.FRAGMENT_CHAT:
            return new FragmentChat().newInstance();
            default:
                throw new RuntimeException("Unknown screen key");
    }
}