Java Json不显示url数据

我正在尝试从Google电子表格中获取JSON数据，但它没有显示。我不知道为什么。我认为我的JSON响应与match类不匹配。请查看并帮助我解决问题

这是我的AsyncResult界面

package com.textview.android.jsonsuccessful；
导入org.json.JSONObject；
接口异步结果{
void onResult（JSONObject对象）；
}

这是我用来获取URL数据的类

package com.textview.android.jsonsuccessful;
import android.os.AsyncTask;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;


public class DownloadWebpageTask extends AsyncTask<String, Void, String> {
AsyncResult callback;

public DownloadWebpageTask(AsyncResult callback) {
    this.callback = callback;
}

  @Override
  protected String doInBackground(String... urls) {

     // params comes from the execute() call: params[0] is the url.
     try {
          return downloadUrl(urls[0]);
      } catch (IOException e) {
          return "Unable to download the requested page.";
    }
  }

  // onPostExecute displays the results of the AsyncTask.
  @Override
  protected void onPostExecute(String result) {
     // remove the unnecessary parts from the response and construct a JSON
    int start = result.indexOf("{", result.indexOf("{") + 1);
    int end = result.lastIndexOf("}");
    String jsonResponse = result.substring(start, end);
    try {
        JSONObject team = new JSONObject(jsonResponse);
        callback.onResult(team);
    } catch (JSONException e) {
        e.printStackTrace();
    }
}

  private String downloadUrl(String urlString) throws IOException {
     InputStream is = null;

     try {
         URL url = new URL(urlString);
          HttpURLConnection conn = (HttpURLConnection) url.openConnection();
           conn.setReadTimeout(10000 /* milliseconds */);
         conn.setConnectTimeout(15000 /* milliseconds */);
          conn.setRequestMethod("GET");
           conn.setDoInput(true);
          // Starts the query
             conn.connect();
         int responseCode = conn.getResponseCode();
          is = conn.getInputStream();   

          String contentAsString = convertStreamToString(is);
           return contentAsString;
       } finally {
          if (is != null) {
            is.close();
           }
      }
   }

       private String convertStreamToString(InputStream is) {
        BufferedReader reader = new BufferedReader(new    
      InputStreamReader(is));
       StringBuilder sb = new StringBuilder();

       String line = null;
        try {
        while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
         }
        } catch (IOException e) {
        e.printStackTrace();
        } finally {
        try {
            is.close();
          } catch (IOException e) {
             e.printStackTrace();
        }
        }
       return sb.toString();
    } 
 }

这是我的适配器

package com.textview.android.jsonsuccessful;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

import java.util.ArrayList;


public class TeamsAdapter extends ArrayAdapter<Team> {

Context context;
private ArrayList<Team> teams;

public TeamsAdapter(Context context, int textViewResourceId, ArrayList<Team>   items) {
    super(context, textViewResourceId, items);
    this.context = context;
    this.teams = items;
}

@Override
public View getView(int Code, View convertView, ViewGroup parent) {
    View v = convertView;
    if (v == null) {
        LayoutInflater vi = (LayoutInflater)    context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        v = vi.inflate(R.layout.team, null);
    }
    Team o = teams.get(Code);
    if (o != null) {
        TextView Cod = (TextView) v.findViewById(R.id.Code);
        TextView Name = (TextView) v.findViewById(R.id.Name);
        TextView Father = (TextView) v.findViewById(R.id.Father);
        TextView Comments = (TextView) v.findViewById(R.id.Comments);
        TextView Sessional = (TextView) v.findViewById(R.id.Sessional);


        Cod.setText(String.valueOf(o.getCode()));
        Name.setText(String.valueOf(o.getName()));
        Father.setText(String.valueOf(o.getFatherName()));
        Sessional.setText(String.valueOf(o.getSessionalMarks()));
        Comments.setText(String.valueOf(o.getComments()));

    }
    return v;
}

package com.textview.android.jsonsuccessful；
导入android.content.Context；
导入android.view.LayoutInflater；
导入android.view.view；
导入android.view.ViewGroup；
导入android.widget.ArrayAdapter；
导入android.widget.TextView；
导入java.util.ArrayList；
公共类TeamsAdapter扩展了ArrayAdapter{
语境；
私人ArrayList团队；
公共团队适配器（上下文、int textViewResourceId、ArrayList项）{
super（上下文、textViewResourceId、项）；
this.context=上下文；
此项=项目；
}
@凌驾
公共视图getView（int代码、视图转换视图、视图组父级）{
视图v=转换视图；
如果（v==null）{
LayoutInflater vi=（LayoutInflater）context.getSystemService（context.LAYOUT\u INFLATER\u SERVICE）；
v=vi.充气（R.布局.团队，空）；
}
Team o=teams.get（代码）；
如果（o！=null）{
TextView Cod=（TextView）v.findViewById（R.id.Code）；
TextView Name=（TextView）v.findViewById（R.id.Name）；
TextView父亲=（TextView）v.findViewById（R.id.Father）；
TextView注释=（TextView）v.findViewById（R.id.Comments）；
TextView Sessional=（TextView）v.findviewbyd（R.id.Sessional）；
Cod.setText（String.valueOf（o.getCode（））；
Name.setText（String.valueOf（o.getName（））；
父.setText（String.valueOf（o.getFatherName（））；
Sessional.setText（String.valueOf（o.getSessionalMarks（））；
Comments.setText（String.valueOf（o.getComments（））；
}
返回v；
}

}

这是我的主要xml

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.textview.android.jsonsuccessful.MainActivity">

<ListView
    android:id="@+id/listview"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_below="@+id/btnDownload" />

<Button
    android:id="@+id/btnDownload"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:enabled="false"
    android:onClick="buttonClickHandler"
    android:text="download table"
    />


</RelativeLayout>`

`

这是my team.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">

<TextView
    android:id="@+id/Code"
    android:text="201"
    android:layout_width="0dp"
    android:layout_weight=".35"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Name"
    android:text="ankit"
    android:layout_width="0dp"
    android:layout_weight=".50"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Father"
    android:text="Ramesh"
    android:layout_width="0dp"
    android:layout_weight=".70"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Sessional"
    android:text="maths 15 ,english 20, physics 30,computer 7,Gk 12"
    android:layout_width="0dp"
    android:layout_weight="1.5"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Comments"
    android:text="should put more efforts"
    android:layout_width="0dp"
    android:layout_weight="1"
    android:layout_height="wrap_content" />


</LinearLayout>

---

解析JSON数据时，您正在解析JSON文件中不存在的一个额外对象“Comments”。 因此，您的阵列“团队”没有填充数据

public class MainActivity extends AppCompatActivity {

    private static final String DEBUG_TAG = "HttpExample";
    ArrayList<Team> teams = new ArrayList<Team>();
    ListView listview;
    Button btnDownload;
    TeamsAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        listview = (ListView) findViewById(R.id.listview);
        btnDownload = (Button) findViewById(R.id.btnDownload);
        ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected()) {
            btnDownload.setEnabled(true);
        } else {
            btnDownload.setEnabled(false);
        }
    }

    public void buttonClickHandler(View view) {
        new DownloadWebpageTask(new AsyncResult() {
            @Override
            public void onResult(JSONObject object) {
                processJson(object);
            }
        }).execute("https://spreadsheets.google.com/tq?key=1424bS7kU8nJbHdu4QdoAFdIdWDSnmEnj2NqfMb6rPTU");

    }

    private void processJson(final JSONObject object) {
        try {
            JSONArray rows = object.getJSONArray("rows");
            for (int r = 0; r < rows.length(); ++r) {
                JSONObject row = rows.getJSONObject(r);
                JSONArray columns = row.getJSONArray("c");
                int Code = columns.getJSONObject(0).getInt("v");
                String Name = columns.getJSONObject(1).getString("v");
                String Father = columns.getJSONObject(3).getString("v");
                String Sessional = columns.getJSONObject(4).getString("v");
                //String Comments = columns.getJSONObject(5).getString("v");
                String Comments = "Error";
                Team team = new Team(Code, Name, Father, Sessional, Comments);
                teams.add(team);
                }
            adapter = new TeamsAdapter(MainActivity.this, R.layout.team, teams);
            listview.setAdapter(adapter);
         } catch (JSONException e) {
             e.printStackTrace();
         }
     }
}

public类MainActivity扩展了AppCompatActivity{
私有静态最终字符串DEBUG_TAG=“HttpExample”；
ArrayList团队=新建ArrayList（）；
列表视图列表视图；
按钮B卸载；
TeamsAdapter适配器；
@凌驾
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.main）；
listview=（listview）findViewById（R.id.listview）；
btnDownload=（按钮）findViewById（R.id.btnDownload）；
ConnectivityManager connMgr=（ConnectivityManager）getSystemService（Context.CONNECTIVITY_服务）；
NetworkInfo NetworkInfo=connMgr.getActiveNetworkInfo（）；
if（networkInfo！=null&&networkInfo.isConnected（））{
btnDownload.setEnabled（true）；
}否则{
btnDownload.setEnabled（false）；
}
}
公共无效按钮ClickHandler（视图）{
新建下载WebPagetTask（新建AsyncResult（））{
@凌驾
公共void onResult（JSONObject对象）{
processJson（对象）；
}
}).执行（”https://spreadsheets.google.com/tq?key=1424bS7kU8nJbHdu4QdoAFdIdWDSnmEnj2NqfMb6rPTU");
}
私有void processJson（最终JSONObject对象）{
试一试{
JSONArray rows=object.getJSONArray（“rows”）；
对于（int r=0；r

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">

<TextView
    android:id="@+id/Code"
    android:text="201"
    android:layout_width="0dp"
    android:layout_weight=".35"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Name"
    android:text="ankit"
    android:layout_width="0dp"
    android:layout_weight=".50"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Father"
    android:text="Ramesh"
    android:layout_width="0dp"
    android:layout_weight=".70"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Sessional"
    android:text="maths 15 ,english 20, physics 30,computer 7,Gk 12"
    android:layout_width="0dp"
    android:layout_weight="1.5"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/Comments"
    android:text="should put more efforts"
    android:layout_width="0dp"
    android:layout_weight="1"
    android:layout_height="wrap_content" />


</LinearLayout>

public class MainActivity extends AppCompatActivity {

    private static final String DEBUG_TAG = "HttpExample";
    ArrayList<Team> teams = new ArrayList<Team>();
    ListView listview;
    Button btnDownload;
    TeamsAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        listview = (ListView) findViewById(R.id.listview);
        btnDownload = (Button) findViewById(R.id.btnDownload);
        ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected()) {
            btnDownload.setEnabled(true);
        } else {
            btnDownload.setEnabled(false);
        }
    }

    public void buttonClickHandler(View view) {
        new DownloadWebpageTask(new AsyncResult() {
            @Override
            public void onResult(JSONObject object) {
                processJson(object);
            }
        }).execute("https://spreadsheets.google.com/tq?key=1424bS7kU8nJbHdu4QdoAFdIdWDSnmEnj2NqfMb6rPTU");

    }

    private void processJson(final JSONObject object) {
        try {
            JSONArray rows = object.getJSONArray("rows");
            for (int r = 0; r < rows.length(); ++r) {
                JSONObject row = rows.getJSONObject(r);
                JSONArray columns = row.getJSONArray("c");
                int Code = columns.getJSONObject(0).getInt("v");
                String Name = columns.getJSONObject(1).getString("v");
                String Father = columns.getJSONObject(3).getString("v");
                String Sessional = columns.getJSONObject(4).getString("v");
                //String Comments = columns.getJSONObject(5).getString("v");
                String Comments = "Error";
                Team team = new Team(Code, Name, Father, Sessional, Comments);
                teams.add(team);
                }
            adapter = new TeamsAdapter(MainActivity.this, R.layout.team, teams);
            listview.setAdapter(adapter);
         } catch (JSONException e) {
             e.printStackTrace();
         }
     }
}