Question

我是新的JSON android工作室我正在做一个非常简单的JSON事情而且我无法获得JSONArray名称。我只想显示＆＃34;用户名＆＃34;参数。

这是JSON：

[
 {
   id: 1,
   name: "Leanne Graham",
   username: "Bret",
   email: "Sincere@april.biz",
   address: {
   street: "Kulas Light",
   suite: "Apt. 556",
city: "Gwenborough",
zipcode: "92998-3874",
geo: {
lat: "-37.3159",
lng: "81.1496"
}
},
phone: "1-770-736-8031 x56442",
website: "hildegard.org",
company: {
name: "Romaguera-Crona",
catchPhrase: "Multi-layered client-server neural-net",
bs: "harness real-time e-markets"
}
},
{
id: 2,
name: "Ervin Howell",
username: "Antonette",
email: "Shanna@melissa.tv",
address: {
street: "Victor Plains",
suite: "Suite 879",
city: "Wisokyburgh",
zipcode: "90566-7771",
geo: {
lat: "-43.9509",
lng: "-34.4618"
}
},
phone: "010-692-6593 x09125",
website: "anastasia.net",
company: {
name: "Deckow-Crist",
catchPhrase: "Proactive didactic contingency",
bs: "synergize scalable supply-chains"
}
},
{
id: 3,
name: "Clementine Bauch",
username: "Samantha",
email: "Nathan@yesenia.net",
address: {
street: "Douglas Extension",
suite: "Suite 847",
city: "McKenziehaven",
zipcode: "59590-4157",
geo: {
lat: "-68.6102",
lng: "-47.0653"
}
},
phone: "1-463-123-4447",
website: "ramiro.info",
company: {
name: "Romaguera-Jacobson",
catchPhrase: "Face to face bifurcated interface",
bs: "e-enable strategic applications"
}
},
{
id: 4,
name: "Patricia Lebsack",
username: "Karianne",
email: "Julianne.OConner@kory.org",
address: {
street: "Hoeger Mall",
suite: "Apt. 692",
city: "South Elvis",
zipcode: "53919-4257",
geo: {
lat: "29.4572",
lng: "-164.2990"
}
},
phone: "493-170-9623 x156",
website: "kale.biz",
company: {
name: "Robel-Corkery",
catchPhrase: "Multi-tiered zero tolerance productivity",
bs: "transition cutting-edge web services"
}
},
{
id: 5,
name: "Chelsey Dietrich",
username: "Kamren",
email: "Lucio_Hettinger@annie.ca",
address: {
street: "Skiles Walks",
suite: "Suite 351",
city: "Roscoeview",
zipcode: "33263",
geo: {
lat: "-31.8129",
lng: "62.5342"
}
},
phone: "(254)954-1289",
website: "demarco.info",
company: {
name: "Keebler LLC",
catchPhrase: "User-centric fault-tolerant solution",
bs: "revolutionize end-to-end systems"
}
},
{
id: 6,
name: "Mrs. Dennis Schulist",
username: "Leopoldo_Corkery",
email: "Karley_Dach@jasper.info",
address: {
street: "Norberto Crossing",
suite: "Apt. 950",
city: "South Christy",
zipcode: "23505-1337",
geo: {
lat: "-71.4197",
lng: "71.7478"
}
},
phone: "1-477-935-8478 x6430",
website: "ola.org",
company: {
name: "Considine-Lockman",
catchPhrase: "Synchronised bottom-line interface",
bs: "e-enable innovative applications"
}
},
{
id: 7,
name: "Kurtis Weissnat",
username: "Elwyn.Skiles",
email: "Telly.Hoeger@billy.biz",
address: {
street: "Rex Trail",
suite: "Suite 280",
city: "Howemouth",
zipcode: "58804-1099",
geo: {
lat: "24.8918",
lng: "21.8984"
}
},
phone: "210.067.6132",
website: "elvis.io",
company: {
name: "Johns Group",
catchPhrase: "Configurable multimedia task-force",
bs: "generate enterprise e-tailers"
}
},
{
id: 8,
name: "Nicholas Runolfsdottir V",
username: "Maxime_Nienow",
email: "Sherwood@rosamond.me",
address: {
street: "Ellsworth Summit",
suite: "Suite 729",
city: "Aliyaview",
zipcode: "45169",
geo: {
lat: "-14.3990",
lng: "-120.7677"
}
},
phone: "586.493.6943 x140",
website: "jacynthe.com",
company: {
name: "Abernathy Group",
catchPhrase: "Implemented secondary concept",
bs: "e-enable extensible e-tailers"
}
},
{
id: 9,
name: "Glenna Reichert",
username: "Delphine",
email: "Chaim_McDermott@dana.io",
address: {
street: "Dayna Park",
suite: "Suite 449",
city: "Bartholomebury",
zipcode: "76495-3109",
geo: {
lat: "24.6463",
lng: "-168.8889"
}
},
phone: "(775)976-6794 x41206",
website: "conrad.com",
company: {
name: "Yost and Sons",
catchPhrase: "Switchable contextually-based project",
bs: "aggregate real-time technologies"
}
},
{
id: 10,
name: "Clementina DuBuque",
username: "Moriah.Stanton",
email: "Rey.Padberg@karina.biz",
address: {
street: "Kattie Turnpike",
suite: "Suite 198",
city: "Lebsackbury",
zipcode: "31428-2261",
geo: {
lat: "-38.2386",
lng: "57.2232"
}
},
phone: "024-648-3804",
website: "ambrose.net",
company: {
name: "Hoeger LLC",
catchPhrase: "Centralized empowering task-force",
bs: "target end-to-end models"
}
}
]

这是我的代码：

package com.example.roa.jasonhw_31116;

import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.TextView;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

public class MainActivity extends AppCompatActivity {

TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    textView = (TextView) findViewById(R.id.textView);
    JasonConn jasonConn = new JasonConn();
    jasonConn.execute("http://jsonplaceholder.typicode.com/users");
}


public class JasonConn extends AsyncTask<String, Void, String >{


    HttpURLConnection connection = null;
    BufferedReader reader = null;
    String result = "";
    String username =  "";


    @Override
    protected String doInBackground(String... params) {
        try {
            URL url = new URL(params[0]);
            //  open the connection to the server (send request)
            connection = (HttpURLConnection) url.openConnection();
            // check if response code is ok!
            if(connection.getResponseCode() != HttpURLConnection.HTTP_OK){
                return "Error from server";
            }
            reader = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            String line;
            if((line = reader.readLine()) != null){
                result += line;
            }

            JSONArray jArray = new JSONArray(result);

            for(int i = 0; i<jArray.length(); i++){
                JSONObject jRealObj = jArray.getJSONObject(i);
                username += jRealObj.getString("username");

            }

        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return username;
    }

    @Override
    protected void onPostExecute(String s) {

            textView.setText(username);

    }
 }
}

感谢所有!!

Answer 1

您没有正确阅读结果。

更改

if((line = reader.readLine()) != null){
        result += line;
}

到

StringBuilder sb = new StringBuilder();
while ((line = reader.readLine()) != null) {
            sb.append(line + "\n");
}
result = sb.toString();

Answer 2

只知道。我再次尝试你给出的解决方案，但没有 StringBuilder（），它工作得很好。代码看起来像这样：

 while ((line = reader.readLine()) != null) {
                result += line + "\n";
            }

再次感谢：）

没有数组名称的JSONArray

2 个答案: