AsyncTask ListView - JSON android studio错误

Question

我正在Eclipse上开发一个应用程序。这是一个简单的应用程序，基本上它只是显示来自Java EE服务器的数据。在Eclipse上它运行良好，然后我需要迁移到Android Studio，复制应用程序，同样的事情。但是现在ListView并没有加载来自服务器的数据，我不知道为什么。

这里是我的AsyncTask类：

package com.tumta.henrique.teste; 

    import java.io.IOException; 
    import java.io.InputStream; 
    import java.io.InputStreamReader; 
    import java.io.Reader; 
    import java.net.HttpURLConnection; 
    import java.net.URL; 
    import java.util.ArrayList; 
    import java.util.List; 

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

    import android.os.AsyncTask; 

    public class ConsultaEntidades extends AsyncTask<Void, Void, List<String>> { 

     private ConsultaConcluidaListener listener; 

     private static final String URL_STRING = "http://192.168.0.14:7001/com.henrique.rest/api/v1/status/entidade/"; 

     public ConsultaEntidades(ConsultaConcluidaListener listener) { 
      this.listener = listener; 
     } 

     @Override 
     protected List<String> doInBackground(Void... arg0) { 
      try { 
       String resultado = ConsultaServidor(); 
       return InterpretaResultado(resultado); 
      } catch (IOException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } catch (JSONException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } 
      return null; 
     } 

     private List<String> InterpretaResultado(String resultado) throws JSONException { 
      JSONObject object = new JSONObject(resultado); 
      JSONArray jsonArray = object.getJSONArray("entidade"); 
      List<String> listaNomes = new ArrayList<String>(); 
      for (int i = 0; i < jsonArray.length(); i++) { 
       JSONObject jsonWaether = jsonArray.getJSONObject(i); 
       //int id = jsonWaether.getInt("ent_id"); 
       String nome = jsonWaether.getString("ent_nome"); 
       listaNomes.add(i, nome); 
      } 

      return listaNomes; 
     } 

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

      try { 
       URL url = new URL(URL_STRING); 
       HttpURLConnection conn = (HttpURLConnection) url.openConnection(); 
       conn.setConnectTimeout(10000); 
       conn.setReadTimeout(15000); 
       conn.setRequestMethod("GET"); 
       conn.setDoInput(true); 
       conn.connect(); 
       conn.getResponseCode(); 

       is = conn.getInputStream(); 

       Reader reader = null; 
       reader = new InputStreamReader(is); 
       char[] buffer = new char[2048]; 
       reader.read(buffer); 
       return new String(buffer); 
      } finally { 
       if (is != null) { 
        is.close(); 
       } 
      } 
     } 

     @Override 
     protected void onPostExecute(List<String> result) { 
      listener.onConsultaConcluida(result); 
      super.onPostExecute(result); 
     } 

     public interface ConsultaConcluidaListener { 
      void onConsultaConcluida(List<String> result); 
     } 
    } 

我的片段：

package com.tumta.henrique.teste; 


import android.app.Activity; 
import android.os.Bundle; 
import android.support.v4.app.Fragment; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.ArrayAdapter; 
import android.widget.ListView; 

import com.tumta.henrique.teste.ConsultaEntidades.*; 
import java.util.List; 


/** 
* A simple {@link Fragment} subclass. 
*/ 
public class EntidadeFragment extends Fragment implements ConsultaConcluidaListener { 

    private static final String ARG_SECTION_NUMBER = "section_number"; 

    public EntidadeFragment() { 
     // Required empty public constructor 
    } 


    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
          Bundle savedInstanceState) { 
     // Inflate the layout for this fragment 
     return inflater.inflate(R.layout.fragment_entidade, container, false); 
    } 

    @Override 
    public void onAttach(Activity activity) { 
     super.onAttach(activity); 
    } 

    public static EntidadeFragment newInstance(int sectionNumber){ 
     EntidadeFragment frag = new EntidadeFragment(); 
     Bundle args = new Bundle(); 
     args.putInt(ARG_SECTION_NUMBER, sectionNumber); 
     frag.setArguments(args); 
     return frag; 
    } 

    @Override 
    public void onConsultaConcluida(List<String> result) { 
     ListView listaEntidades = (ListView) getView().findViewById(R.id.listaentidades); 
     ArrayAdapter arrayAdapter = new ArrayAdapter<>(getView().getContext(),android.R.layout.simple_list_item_1, result); 
     listaEntidades.setAdapter(arrayAdapter); 
    } 
} 

我的MainActivity：

package com.tumta.henrique.teste; 

import android.app.Activity; 
import android.support.v7.app.ActionBarActivity; 
import android.support.v7.app.ActionBar; 
import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentManager; 
import android.content.Context; 
import android.os.Build; 
import android.os.Bundle; 
import android.view.Gravity; 
import android.view.LayoutInflater; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.view.ViewGroup; 
import android.support.v4.widget.DrawerLayout; 
import android.widget.ArrayAdapter; 
import android.widget.TextView; 
import com.tumta.henrique.teste.EntidadeFragment; 


public class MainActivity extends ActionBarActivity 
     implements NavigationDrawerFragment.NavigationDrawerCallbacks { 

    /** 
    * Fragment managing the behaviors, interactions and presentation of the navigation drawer. 
    */ 
    private NavigationDrawerFragment mNavigationDrawerFragment; 

    /** 
    * Used to store the last screen title. For use in {@link #restoreActionBar()}. 
    */ 
    private CharSequence mTitle; 

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

     mNavigationDrawerFragment = (NavigationDrawerFragment) 
       getSupportFragmentManager().findFragmentById(R.id.navigation_drawer); 
     mTitle = getTitle(); 

     // Set up the drawer. 
     mNavigationDrawerFragment.setUp(
       R.id.navigation_drawer, 
       (DrawerLayout) findViewById(R.id.drawer_layout)); 
    } 

    @Override 
    public void onNavigationDrawerItemSelected(int position) { 
     // update the main content by replacing fragments 
     FragmentManager fragmentManager = getSupportFragmentManager(); 
     switch(position + 1){ 
      case 1: 
       fragmentManager.beginTransaction() 
         .replace(R.id.container, PlaceholderFragment.newInstance(position + 1)) 
         .commit(); 
      break; 
      case 2: 
       fragmentManager.beginTransaction() 
         .replace(R.id.container, EntidadeFragment.newInstance(position + 1)) 
         .commit(); 
       break; 

     } 
     //fragmentManager.beginTransaction() 
     //  .replace(R.id.container, PlaceholderFragment.newInstance(position + 1)) 
     //  .commit(); 
    } 

    public void onSectionAttached(int number) { 
     switch (number) { 
      case 1: 
       mTitle = getString(R.string.title_section1); 
       break; 
      case 2: 
       mTitle = "Entidades"; 
       break; 
      case 3: 
       mTitle = getString(R.string.title_section3); 
       break; 
     } 
    } 

    public void restoreActionBar() { 
     ActionBar actionBar = getSupportActionBar(); 
     actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD); 
     actionBar.setDisplayShowTitleEnabled(true); 
     actionBar.setTitle(mTitle); 
    } 


    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     if (!mNavigationDrawerFragment.isDrawerOpen()) { 
      // Only show items in the action bar relevant to this screen 
      // if the drawer is not showing. Otherwise, let the drawer 
      // decide what to show in the action bar. 
      getMenuInflater().inflate(R.menu.main, menu); 
      restoreActionBar(); 
      return true; 
     } 
     return super.onCreateOptionsMenu(menu); 
    } 

    @Override 
    public boolean onOptionsItemSelected(MenuItem item) { 
     // Handle action bar item clicks here. The action bar will 
     // automatically handle clicks on the Home/Up button, so long 
     // as you specify a parent activity in AndroidManifest.xml. 
     int id = item.getItemId(); 

     //noinspection SimplifiableIfStatement 
     if (id == R.id.action_settings) { 
      return true; 
     } 

     return super.onOptionsItemSelected(item); 
    } 

    /** 
    * A placeholder fragment containing a simple view. 
    */ 
    public static class PlaceholderFragment extends Fragment { 
     /** 
     * The fragment argument representing the section number for this 
     * fragment. 
     */ 
     private static final String ARG_SECTION_NUMBER = "section_number"; 

     /** 
     * Returns a new instance of this fragment for the given section 
     * number. 
     */ 
     public static PlaceholderFragment newInstance(int sectionNumber) { 
      PlaceholderFragment fragment = new PlaceholderFragment(); 
      Bundle args = new Bundle(); 
      args.putInt(ARG_SECTION_NUMBER, sectionNumber); 
      fragment.setArguments(args); 
      return fragment; 
     } 

     public PlaceholderFragment() { 
     } 

     @Override 
     public View onCreateView(LayoutInflater inflater, ViewGroup container, 
           Bundle savedInstanceState) { 
      View rootView = inflater.inflate(R.layout.fragment_main, container, false); 
      return rootView; 
     } 

     @Override 
     public void onAttach(Activity activity) { 
      super.onAttach(activity); 
      ((MainActivity) activity).onSectionAttached(
        getArguments().getInt(ARG_SECTION_NUMBER)); 
     } 
    } 

} 

我的清单文件：

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="com.tumta.henrique.teste" > 

    <uses-permission android:name="android.permission.INTERNET"/> 

    <application 
     android:allowBackup="true" 
     android:icon="@mipmap/ic_launcher" 
     android:label="@string/app_name" 
     android:theme="@style/AppTheme" > 
     <activity 
      android:name=".MainActivity" 
      android:label="@string/app_name" > 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 

       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 
    </application> 

</manifest> 

再次说明：当我使用Eclipse时，它工作正常，现在我使用Android Studio，它不会从服务器获取数据。

Answer 1

问题是我忘了在片段上的onCreateView上打电话给我的班级。谢谢！