Question

我试图检索JSONArray数据，但是代码只是解析JSONObject，我无法弄清楚如何做到这一点

package com.example.darrenwilliamson.st3;

import android.app.Activity;
import android.app.ProgressDialog;
import android.os.Bundle;
import android.util.Log;
import android.widget.ListView;
import android.widget.Toast;

import com.android.volley.AuthFailureError;
import com.android.volley.NetworkError;
import com.android.volley.NoConnectionError;
import com.android.volley.ParseError;
import com.android.volley.Response;
import com.android.volley.ServerError;
import com.android.volley.TimeoutError;
import com.android.volley.VolleyError;
import com.android.volley.VolleyLog;
import com.android.volley.toolbox.JsonArrayRequest;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.util.ArrayList;
import java.util.List;

public class ActivityNews extends Activity {

    // Log tag
    private static final String TAG = ActivityNews.class.getSimpleName();

    // News json url
    String url = "https://newsapi.org/v1/articles?source=bbc-sport&sortBy=top&apiKey=45570115d8af4e89880161af1c5fa087";

    private ProgressDialog pDialog;
    private List<DataSet> dataList = new ArrayList<DataSet>();
    private ListView listView;
    private CustomListAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_news);

        listView = (ListView) findViewById(R.id.list);
        adapter = new CustomListAdapter(this, dataList);
        listView.setAdapter(adapter);

        pDialog = new ProgressDialog(this);
        // Showing progress dialog before making http request
        pDialog.setMessage("Loading...");
        pDialog.show();


        // Creating volley request obj
        JsonArrayRequest newsReq = new JsonArrayRequest(url,
                new Response.Listener<JSONArray>() {


                    @Override
                    public void onResponse(JSONArray response) {

                        hidePDialog();


                        // Parsing json

                            try {

                                JSONArray jr = new JSONArray(url);
                                JSONObject jb = (JSONObject)jr.getJSONObject(0);
                                JSONArray st = jb.getJSONArray("articles");
                                for(int i=0;i<st.length();i++) {


                                    JSONObject obj = response.getJSONObject(i);
                                    DataSet news = new DataSet();

                                    news.setAuthor_(obj.getString("author"));
                                    news.setTitle_(obj.getString("title"));
                                    news.setDescription_(obj.getString("description"));
                                    news.setImage_(obj.getString("url"));
                                    news.setUrlToImage_(obj.getString("urlToImage"));
                                    news.setPublished_(obj.getString("published"));


                                    // adding news to news array
                                    dataList.add(news);
                                }

                            } catch (final JSONException e) {
                                Log.e(TAG, "Json parsing error: " + e.getMessage());
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(getApplicationContext(),
                                                "Json parsing error: " + e.getMessage(),
                                                Toast.LENGTH_LONG).show();
                                    }
                                });
                            }



                        // notifying list adapter about data changes
                        // so that it renders the list view with updated data
                        adapter.notifyDataSetChanged();
                    }
                },

                new Response.ErrorListener() {


            @Override
            public void onErrorResponse(VolleyError error) {
                VolleyLog.d(TAG, "Error: " + error.getMessage());
                hidePDialog();

                if (error instanceof TimeoutError) {
                    Log.e(TAG, "TimeoutError");
                } else if (error instanceof NoConnectionError) {
                    Log.e(TAG,"NoConnectionError");
                } else if (error instanceof AuthFailureError) {
                    Log.e(TAG,"AuthFailureError");
                } else if (error instanceof ServerError) {
                    Log.e(TAG,"ServerError");
                } else if (error instanceof NetworkError) {
                    Log.e(TAG,"NetworkError");
                } else if (error instanceof ParseError) {
                    Log.e(TAG,"ParseError" + error.getMessage());
                }

            }
        });

        // Adding request to request queue
        AppController.getInstance().addToRequestQueue(newsReq);
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        hidePDialog();
    }

    private void hidePDialog() {
        if (pDialog != null) {
            pDialog.dismiss();
            pDialog = null;
        }
    }

}

基本上我要求的只是数据作者，标题，描述，URL等。请帮忙

错误：

ParseErrororg.json.JSONException:

Answer 1

您的解析的JSON是json对象而不是JSON Array.make Json对象请求

JSONArray解析问题

1 个答案: