java - 从 JSON 数据清空 RecyclerView

Question

感谢迄今为止提供的所有帮助。这是我提出的一个有点奇怪的问题。我正在发出网络请求以从服务器获取数据并使用 json 字符串更新 UI。我已经正确完成了 json 解析，并将结果打印在我的日志猫中，如下所示:

11-17 22:57:02.143 25111-25111/com.billionusers.tingting D/MyReviewsFragment: FAN Lib My Reviews Response is:   {"success":true,"reviews":[{"_id":"5a0ef724b004b53e48eafaf6","updatedAt":"2017-11-17T14:50:12.700Z","createdAt":"2017-11-17T14:50:12.700Z","for":"5a0d90b8f690f625df370bb6","by":"5a0aa8f7aecfbc47838fb89b","body":"Lorem Ipsum","__v":0}]}

我使用了模型类来保存评论并从 recyclerview 过程创建了适配器。我的模型类包含来自服务器的评论数据的名称、图像、时间和正文。

这是我的适配器代码:

public class ReviewsAdapter extends RecyclerView.Adapter<MyReviewsHolder> {

private final Context context;
private List<Reviews> itemsList;

public ReviewsAdapter(Context context, List<Reviews> itemsList) {
    this.context = context;
    this.itemsList = itemsList;
}

@Override
public MyReviewsHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.my_reviews_item_layout, parent, false);
    return new MyReviewsHolder(view);
}

@Override
public void onBindViewHolder(MyReviewsHolder viewholder, int position) {
    Reviews reviews = itemsList.get(position);
    Picasso.with(context)
            .load(reviews.getReviewerImg())
            .into(viewholder.reviewerProfileImg);
    viewholder.reviewerNameTV.setText(reviews.getReviewerName());
    viewholder.reviewTimeTV.setText(reviews.getReviewTime());
    viewholder.reviewBodyTV.setText(reviews.getReviewBody());
}

@Override
public int getItemCount() {
    if (itemsList == null) {
        return 0;
    }
    return itemsList.size();
}
}

在我的 fragment 中，我已经初始化了 View 和字段，例如:

private TextView dummy;
private RecyclerView my_reviews_recyclerView;

private List<Reviews> itemsList = new ArrayList<>();
private ReviewsAdapter adapter;

private boolean success;

public MyReviewsFragment() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View view = inflater.inflate(R.layout.fragment_my_reviews, container, false);

    dummy = view.findViewById(R.id.dummy);

    my_reviews_recyclerView = view.findViewById(R.id.my_reviews_recyclerView);
    my_reviews_recyclerView.setHasFixedSize(true);
    my_reviews_recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));

    fetchMyReviews();

    return view;
}

用于发出网络请求的代码。我还在这里完成了 json 解析，并尝试使用数据更新 UI，但 recyclerview 显示空状态。

这是网络和 UI 代码:

AndroidNetworking.get(Constants.GET_MY_REVIEWS_ENDPOINT)
            .addHeaders("x-access-token", token)
            .setTag("Get My Reviews")
            .setPriority(Priority.HIGH)
            .build()
            .getAsJSONObject(new JSONObjectRequestListener() {
                @Override
                public void onResponse(JSONObject response) {
                    Log.d(TAG, "FAN Lib My Reviews Response is: \t" + response.toString());

                    try {
                        JSONObject object = response.getJSONObject("");
                        success = (boolean) object.get("success");

                        JSONArray reviewsArray = object.getJSONArray("reviews");
                        for (int i = 0; i < reviewsArray.length(); i++){
                            JSONObject body = reviewsArray.getJSONObject(i);
                            String revId = body.getString("_id");
                            String revTime = body.getString("createdAt");
                            String revFor = body.getString("for");
                            String revBy = body.getString("by");
                            String revMsgBody = body.getString("body");

                            // TODO: 11/17/2017  Get Reviewer Details

                            //Reviews reviews = new Reviews("", "Demo User", revMsgBody, revTime);
                            Reviews reviews = new Reviews();
                            reviews.setReviewerName("Abhiram Labhani");
                            reviews.setReviewerImg("");
                            reviews.setReviewBody(revMsgBody);
                            reviews.setReviewTime(revTime);
                            itemsList.add(reviews);

                            adapter = new ReviewsAdapter(getActivity(), itemsList);
                            my_reviews_recyclerView.setAdapter(adapter);

                            if (adapter.getItemCount() > 0){
                                dummy.setVisibility(View.GONE);
                                Log.d(TAG, "Adapter size is:\t" + adapter.getItemCount());
                            } else {
                                dummy.setVisibility(View.VISIBLE);
                                Log.d(TAG, "Adapter size is:\t" + adapter.getItemCount());
                            }

                        }

                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }

                @Override
                public void onError(ANError anError) {

                }
            });

有人可以指出我缺少什么，因为我不知道问题出在哪里。谢谢。

Answer 1

这是错误:

JSONObject object = response.getJSONObject("");
                        success = (boolean) object.get("success");
                        JSONArray reviewsArray = object.getJSONArray("reviews");

为什么使用响应中的空 jsonobject？直接使用:

                    success = (boolean) response.get("success");
                    JSONArray reviewsArray = response.getJSONArray("reviews");