База данных MySQL для android ListView

Question

Я пытаюсь загрузить данные из базы данных MySQL в android ListView. Это один пример я видел: http://codeoncloud.blogspot.com/2013/07/android-mysql-php-json-tutorial.html

Вот мой код:

public class AbCdEfGh extends ActionBarActivity { 

private String jsonResult; 
private String url = "http://merosong.byethost24.com/android_php_files_management/connection.php"; 
private ListView listView; 
ProgressDialog pDialog; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 

    //showing a ProgressDialog 
    pDialog = new ProgressDialog(this); 
    pDialog = ProgressDialog.show(this, "", "Loading", true); 

    setContentView(R.layout.activity_choose); 
    listView = (ListView) findViewById(R.id.list_main); 

    accessWebService(); 

} 

@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    // Inflate the menu; this adds items to the action bar if it is present 
    getMenuInflater().inflate(R.menu.menu_choose, menu); 
    return true; 
} 

// Async Task to access the web 
private class JsonReadTask extends AsyncTask<String, Void, String> { 
    @Override 
    protected String doInBackground(String... params) { 
     HttpClient httpclient = new DefaultHttpClient(); 
     HttpPost httppost = new HttpPost(params[0]); 
     try { 
      HttpResponse response = httpclient.execute(httppost); 
      jsonResult = inputStreamToString(
        response.getEntity().getContent()).toString(); 

     } catch (ClientProtocolException e) { 
      e.printStackTrace(); 

     } catch (IOException e) { 
      e.printStackTrace(); 

     } 
     return null; 


    } 

    private StringBuilder inputStreamToString(InputStream is) { 
     String rLine = ""; 
     StringBuilder answer = new StringBuilder(); 
     BufferedReader rd = new BufferedReader(new InputStreamReader(is)); 
     try { 
      while ((rLine = rd.readLine()) != null) { 
       answer.append(rLine); 
      } 
     } catch (IOException e) { 


     } 
     return answer; 
    } 

    @Override 
    protected void onPostExecute(String result) { 
     pDialog.dismiss(); 
     ListDrwaer(); 

    } 



}// end async task 

public void accessWebService() { 
    JsonReadTask task = new JsonReadTask(); 
    // passes values for the urls string array 
    task.execute(new String[]{url}); 
} 

// build hash set for list view 
public void ListDrwaer() { 
    List<Map<String, String>> trackList = new ArrayList<Map<String, String>>(); 

    try { 
     JSONObject jsonResponse = new JSONObject(jsonResult); 
     JSONArray jsonMainNode = jsonResponse.optJSONArray("mstracks"); 
     for (int i = 0; i < jsonMainNode.length(); i++) { 
      JSONObject jsonChildNode = jsonMainNode.getJSONObject(i); 
      String name = jsonChildNode.optString("name"); 
      String outPut = name + ""; 
      trackList.add(createEmployee("merosongayush", outPut)); 
     } 

    } catch (JSONException e) { 

    } 


    SimpleAdapter simpleAdapter = new SimpleAdapter(this, trackList, 
      android.R.layout.simple_list_item_1, 
      new String[]{"merosongayush"}, new int[]{android.R.id.text1}); 
    listView.setAdapter(simpleAdapter); 

} 

private HashMap<String, String> createEmployee(String name, String link) { 
    HashMap<String, String> finalNameLink = new HashMap<String, String>(); 
    finalNameLink.put(name, link); 
    return finalNameLink; 
} 

}

Я не получаю ничего в моем андроиде деятельности.

Мой выход connection.php:

http://merosong.byethost24.com/android_php_files_management/connection.php

Пожалуйста, помогите. Заранее спасибо.

Answer 1

Это может быть потому, что ваша функция doInBackground не возвращает ничего.