Java Android应用程序不显示来自Web服务器的数据

我想开发一个android应用程序，它从web服务器（我在www.byethost.com上的免费域帐户）获取数据，并在我的android应用程序的列表视图中显示数据。过去5天我遇到的问题是，当我在本地主机（WAMP）上运行我的PHP脚本并使用此链接从emulator调用它时，它运行得很好。但当我将此脚本放在免费域面板上并从此链接调用时，它不会在我使用USB电缆连接到PC的真实设备上显示任何内容。自从过去5天以来，我已经搜索了很多链接，但它没有显示任何与我的问题相关的信息。先谢谢你

MainActivity.java

package com.example.abdul.zx;

import android.app.Activity;
import android.content.Intent;
import android.os.AsyncTask;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.params.BasicHttpParams;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;


public class MainActivity extends Activity
{

String myJSON ;
String id;
String name;
private static final String TAG_RESULTS="result";
// private static final String TAG_ID = "id";
private static final String TAG_NAME = "name";
// private static final String TAG_ADD ="address";

JSONArray peoples = null;

ArrayList <HashMap <String, String> > personList;

ListView list;



@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    list = (ListView) findViewById(R.id.listView);
    personList = new ArrayList<HashMap<String,String>>();
    getData();


}


protected void showList(){
    try {
        JSONObject jsonObj = new JSONObject(myJSON);
        peoples = jsonObj.getJSONArray(TAG_RESULTS);

        for(int i=0;i<peoples.length();i++){
            JSONObject c = peoples.getJSONObject(i);
           // id = c.getString(TAG_ID);
            name = c.getString(TAG_NAME);
           // String address = c.getString(TAG_ADD);

            HashMap<String,String> persons = new HashMap<String,String>();

         //   persons.put(TAG_ID,id);
            persons.put(TAG_NAME,name);
          //  persons.put(TAG_ADD,address);

            personList.add(persons);
        }

        final ListAdapter adapter = new SimpleAdapter
                (MainActivity.this, personList, R.layout.list_item,
                        new String[]{TAG_NAME},
                        new int[]{R.id.name});

        list.setAdapter(adapter);
       list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
           @Override
           public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
               switch(i)
               {
               case 0 :
               Intent appInfo = new Intent(MainActivity.this, Desserts.class);
               startActivity(appInfo);

               break;
               case 1 :
               Intent ap = new Intent(MainActivity.this, MainActivity3.class);
               startActivity(ap);
               break;
               case 2 :
               Intent Info = new Intent(MainActivity.this, Desserts.class);
               startActivity(Info);
               break;
           }}
       });
    } catch (JSONException e) {
        e.printStackTrace();
    }

}

public void getData(){
    class GetDataJSON extends AsyncTask<String, Void, String>{

        @Override
        protected String doInBackground(String... params) {
            DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
            //HttpPost httppost = new HttpPost("http://10.0.2.2/ch.php");
            HttpPost httppost = new HttpPost("http://zamin.byethost14.com/demo.php");
            // Depends on your web service
            httppost.setHeader("Content-type", "application/json");

            InputStream inputStream = null;
            String result = null;
            try {
                HttpResponse response = httpclient.execute(httppost);
                HttpEntity entity = response.getEntity();

                inputStream = entity.getContent();
                // json is UTF-8 by default
                BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
                StringBuilder sb = new StringBuilder();

                String line = null;
                while ((line = reader.readLine()) != null)
                {
                    sb.append(line + "\n");
                }
                result = sb.toString();
            } catch (Exception e) {
                // Oops
            }
            finally {
                try{if(inputStream != null)inputStream.close();}catch(Exception squish){}
            }

            return result;

        }

        @Override
        protected void onPostExecute(String result){
            myJSON=result;
            showList();
        }
    }
    GetDataJSON g = new GetDataJSON();
    g.execute();
}



}

---

我尝试从浏览器访问API链接。您确定这是HTTP Post请求吗？ 试试这个

HttpClient httpclient = new DefaultHttpClient();
HttpGet request = new HttpGet();
URI website = new URI("http://zamin.byethost14.com/demo.php");
request.setURI(website);
HttpResponse response = httpclient.execute(request);

---

任何异常或Logcat？？post ur Logcat或post execute的字符串结果值…没有异常发生。没有输出仅显示背景。@RishadAppat看到我已使用LogcatEdit编辑我的问题运行应用程序后GetDataJSON onPostExecute方法中的'result'值是多少？。当我将POST更改为GET时，它显示此异常java.lang.NullPointerException:尝试调用虚拟方法'int java.lang.String.length（）'在此行的空对象引用上，JSONObject jsonObj=new JSONObject（myJSON）；您的响应格式是JSONArray。试试这个JSONArray jsonObj=newjsonarray（myJSON）；我已经改变了这一点，但没有解决方案仍然是相同的问题MyJSON为空。它没有得到更新。在JSONObject jsonObj=newjsonobject（myJSON）之前确认这一点。这是因为您试图从内部类中修改类变量吗？请尝试以更好的方式将myJSon从AsyncTask传递到Activity。在AsyncTask中创建一个构造函数，该构造函数包含活动对象。现在通过myActivity.myJson=result更新myJson的值；

PropertyFetcher: AdbCommandRejectedException getting properties for device   LC524YE42425: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems   wrong.
Otherwise check for a confirmation dialog on your device.
PropertyFetcher: AdbCommandRejectedException getting properties for device  LC524YE42425: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems  wrong.
Otherwise check for a confirmation dialog on your device.
PropertyFetcher: AdbCommandRejectedException getting properties for device   LC524YE42425: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems  wrong.
Otherwise check for a confirmation dialog on your device.
PropertyFetcher: AdbCommandRejectedException getting properties for device   LC524YE42425: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems  wrong.
Otherwise check for a confirmation dialog on your device.
PropertyFetcher: AdbCommandRejectedException getting properties for device   LC524YE42425: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems  wrong.
Otherwise check for a confirmation dialog on your device.
PropertyFetcher: AdbCommandRejectedException getting properties for device  LC524YE42425: device unauthorized.
This adbd's $ADB_VENDOR_KEYS is not set; try 'adb kill-server' if that seems  wrong.
Otherwise check for a confirmation dialog on your device.

HttpClient httpclient = new DefaultHttpClient();
HttpGet request = new HttpGet();
URI website = new URI("http://zamin.byethost14.com/demo.php");
request.setURI(website);
HttpResponse response = httpclient.execute(request);