JSONArray数据不会显示在Fragment上

Question

我在Fragment上显示JSONArray数据时遇到问题。我已验证我的链接，字符串等。但是在调试控制台上，我的请求显示正确。我怀疑JSONArray请求，但找不到任何错误。

请帮忙！

npm start

这是我的片段

D/Request:::  010-8470-0486 
              010-8472-0964 
              010-8474-2372 
D/Request:::  010-8475-0089 
D/Request:::  010-8475-7585 
              010-8478-0007 
D/Request:::  010-8478-0573 
              010-8479-0311 
              010-8479-9234 
D/Request:::  010-8481-2030 

和ModelDB类

public class FragmentDB extends Fragment {

    private View v;
    private RecyclerView recyclerView;
    private String url = "http://www.example.com/api.php";
    private List<ModelDB> modelDBList;

    public FragmentDB() {
    }

    @SuppressWarnings("UnnecessaryLocalVariable")
    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (Objects.requireNonNull(getActivity()).checkSelfPermission(Manifest.permission.READ_CALL_LOG) != PackageManager.PERMISSION_GRANTED &&
                    getActivity().checkSelfPermission(Manifest.permission.READ_CONTACTS) != PackageManager.PERMISSION_GRANTED &&
                    getActivity().checkSelfPermission(Manifest.permission.READ_PHONE_STATE) != PackageManager.PERMISSION_GRANTED)
                return v;
        } else {
            Intent i10 = new Intent(getActivity(), PermissionActivity.class);
            startActivity(i10);
            Objects.requireNonNull(getActivity()).finish();
        }




        v = inflater.inflate(R.layout.frag_db, container, false);
        recyclerView = v.findViewById(R.id.rv_db);
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(getContext());
        RecyclerView.LayoutManager layoutManager = linearLayoutManager;
        recyclerView.setLayoutManager(layoutManager);
        DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(), linearLayoutManager.getOrientation());

        modelDBList = new ArrayList<>();
        DbRvAdapter adapter = new DbRvAdapter(getContext(), modelDBList);

        recyclerView.setAdapter(adapter);
        adapter.notifyDataSetChanged();
        recyclerView.addItemDecoration(dividerItemDecoration);
        recyclerView.setHasFixedSize(true);
        Objects.requireNonNull(getActivity()).getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
        getDBLogs();
        return v;



    }

    @SuppressWarnings({"LogNotTimber", "deprecation"})
    private void getDBLogs() {
        JsonArrayRequest jsonArrayRequest = new JsonArrayRequest(url, new Response.Listener<JSONArray>() {
                    @Override
                    public void onResponse(JSONArray response) {
                        // Do something with the response

                        try {
                            for ( int i = 0; i < response.length(); i++) {
                                JSONObject obj = response.getJSONObject(i);
                                ModelDB dblist = new ModelDB();
                                dblist.setPhone_number(obj.getString("phone_number"));
                                dblist.setInfo1(obj.getString("info1"));

                                modelDBList.add(dblist);
                                Log.d("Request:: ", obj.getString("phone_number"));


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

                        }
                    }, new Response.ErrorListener() {
                    @Override
                    public void onErrorResponse(VolleyError error) {
                        // Handle error
                        Log.e("Volley", error.toString());
                    }
                });
        RequestQueue rq = Volley.newRequestQueue(Objects.requireNonNull(getActivity()).getApplicationContext());
        rq.add(jsonArrayRequest);

    }

}

和适配器类

public class ModelDB {

    public String phone_number;
    public String info1;

    public ModelDB() {

    }

    public ModelDB(String phone_number, String info1) {
        this.phone_number = phone_number;
        this.info1 = info1;
    }

    public String getPhone_number() {
        return phone_number;
    }

    public void setPhone_number(String phone_number) {
        this.phone_number = phone_number;
    }

    public String getInfo1() {
        return info1;
    }

    public void setInfo1(String info1) {
        this.info1 = info1;
    }

}

对不起，我的英语不好。

Answer 1

在解析网络调用结果之后，您似乎没有更新modelDB的内部适配器列表。

Answer 2

在for循环体之后通知您的适配器，并全局声明适配器

for ( int i = 0; i < response.length(); i++) {
   ............

   modelDBList.add(dblist);

 }
if(dblist != null and dblist.size() > 0){
adapter.notifyDataSetChanged();
}