Question

我有一个功能齐全的回收站视图，当应用程序打开时，该视图作为导航抽屉的一部分打开。我更改了一些代码，并且无意中放错了一些代码，现在打开导航抽屉时，该片段为空白，直到我单击该片段以再次在抽屉中打开它是否显示了recyclerview及其内容。我可以得到一些帮助来确定缺少的代码段吗？

我有一段时间没接触过这段代码了，因为我认为它运行良好，所以我无法再看到代码了，但是我仔细阅读了我用于导航抽屉和recyclerview的教程，以确保他们将单独工作，而且看起来我已经掌握了一切。我检查了一些有关Stack溢出的问题，但它们似乎仅对应于Firebase recyclerview，并没有真正回答我的特定问题。

此页面是初始化抽屉的位置，应调用recyclerview。

protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.front_page);
        android.support.v7.widget.Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        drawer = findViewById(R.id.drawer_front_page);
        NavigationView nV = findViewById(R.id.drawer_view);
        View header = nV.getHeaderView(0);
        nV.setNavigationItemSelectedListener(this);
        callbackManager = CallbackManager.Factory.create();
        connMgr = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(this, drawer, toolbar,
                R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.addDrawerListener(toggle);
        drawer.openDrawer(Gravity.START);
        toggle.syncState();
        nV.setCheckedItem(R.id.list_venue);

        /*ConnectivityManager connMgr = (ConnectivityManager)

                getSystemService(Context.CONNECTIVITY_SERVICE);

        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();

         if(!networkInfo.isConnected()){

         }*/
        //TODO: Create network status check with animation and Dialog
        sharedPreferences = getSharedPreferences(SHARED_PREFS, MODE_PRIVATE);
        isLoggedOut = sharedPreferences.getBoolean(LOGINSTATUS,false);
        drawerProfilePicture = header.findViewById(R.id.drawer_pic_profile);
        drawerUserName = header.findViewById(R.id.drawer_profile_username);
        drawerUserEmail = header.findViewById(R.id.drawer_profile_email);

        if (AccessToken.getCurrentAccessToken() != null && !AccessToken.getCurrentAccessToken().isExpired()) {
            facebookLogin();
        } else {
            inHouseSignUp();
        }
    }

这是recyclerview

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

        if (!Places.isInitialized()) {
            Places.initialize(contextForPlaces, "AIzaSyCKGd3fqmtsDklRGMhnkuIy1GS-j6gRBh8");
        }
        RecyclerView vRV = view.findViewById(R.id.view_venue);
        vRV.setHasFixedSize(true);

        RecyclerView.LayoutManager vLM = new LinearLayoutManager(this.getActivity());
        vAdapter = new VenueAdapter(vIL);
        vAdapter.setOnItemClickListener(this::shareTheView);

        placesClient = Places.createClient(contextForPlaces);


        //TODO: Make App mention when there is no service
        //TODO Figure out animation for scrolling
        //TODO: add code to make sure that the VenueList is complete before displaying it
        //look for transfering keys for the information instead of the information itself

        //TODO: E/RecyclerView: No adapter attached; skipping layout


        for (String club : clubs) {
            FetchPlaceRequest request = FetchPlaceRequest.newInstance(club, placeFields);
            placesClient.fetchPlace(request).addOnSuccessListener((response) -> {
                Place place = response.getPlace();
                PhotoMetadata photoMetadata = Objects.requireNonNull(place.getPhotoMetadatas()).get(0);
                //String attributions = photoMetadata.getAttributions();

                FetchPhotoRequest photoRequest = FetchPhotoRequest.builder(photoMetadata).setMaxHeight(400).setMaxWidth(400).build();
                placesClient.fetchPhoto(photoRequest).addOnSuccessListener((fetchPhotoResponse) -> {

                    Bitmap bitmap = fetchPhotoResponse.getBitmap();

                    vIL.add(new VenueItem( /*Photo*/bitmap, place.getName()));

                    //Log.i(TAG, "Photo Should Be Up");
                    vRV.setLayoutManager(vLM);
                    vRV.setAdapter(vAdapter);
                }).addOnFailureListener((exception) -> {
                    if (exception instanceof ApiException) {
                        ApiException apiException = (ApiException) exception;
                        int statusCode = apiException.getStatusCode();
                        // Handle error with given status code.
                        Log.e(TAG, "Place not found: " + exception.getMessage());
                    }
                });

                Log.i(TAG, "Place found: " + place.getName());
            }).addOnFailureListener((exception) -> {
                if (exception instanceof ApiException) {
                    ApiException apiException = (ApiException) exception;
                    int statusCode = apiException.getStatusCode();
                    // Handle error with given status code.
                    Log.e(TAG, "Place not found: " + exception.getMessage());
                }
            });
        }
        vAdapter.notifyDataSetChanged();

        return view;
    }

所有代码都可以使用，但是在首次调用时无法打开，而我需要手动调用它，以前从未发生过。

Answer 1

在for循环之后尝试一下

for(String club : clubs){}
vAdapter = new VenueAdapter(vIL);
vRV.setLayoutManager(vLM);
vRV.setAdapter(vAdapter);

Answer 2

我找到了要擦除的代码。这段代码指示了如果没有可用的片段，它将在启动时启动

if (savedInstanceState == null) {
        getSupportFragmentManager().beginTransaction().replace(R.id.fragment_container,
                new VenueList()).commit();
        nV.setCheckedItem(R.id.list_venue);
    }

导航抽屉不会自动启动recyclerview片段

2 个答案: