runOnUiThread不在的AsyncTask

Question

運行我編碼的程序，其從MySQL從服務器提取數據（使用JSON）和它更新UI因此，

我讀取兩種類型的數據使用的AsyncTask從服務器

1) Bubble Answers 
2) Comments 

的parseBubbleAnswers方法成功運行，並更新UI， 但parseComments類，這是的AsyncTask，並調用parseComments方法d oInBackground，不運行runOnUiThread(new Runnable() { run() });

誰能幫我解決這個

這裏是我的代碼：

public class FetchServer extends Activity 
{ 
    protected void onCreate(Bundle savedInstanceState) 
    { 
     String photoId = "1"; // photo id for which the data is fetched 
     checkBubbleData(photoId); // which call AsyncTask - 2 differnt calls 
    } 
    public void checkBubbleData(String photoId) 
    { 
     new parseBubbleAnswers().execute(photoId); // to fetch bubble answers 
     new parseComments().execute(photoId); // to fetch comments 
    } 
    class parseBubbleAnswers extends AsyncTask<String, Integer,String> 
    { 

     @Override 
     protected String doInBackground(String... params) 
     { 
      // TODO Auto-generated method stub 
      Looper.prepare(); 
      parseBubbleAnswers(); // which has runOnUiThread(new Runnable() which updates (successfully !) the UI 
      return null; 
     } 
    } 
    class parseComments extends AsyncTask<String, Integer,String> 
    { 

     @Override 
     protected String doInBackground(String... params) 
     { 
      // TODO Auto-generated method stub 
      Looper.prepare(); 

      String parseComReturn = parseComments(); 
      if(parseComReturn=="end") 
      { 
       commentBuilder(); // which will update UI after fetch data by parseComments() method 
      } 
     } 
    } 
    public void commentBuilder() 
    { 
     runOnUiThread(new Runnable() // while debugging, it comes here, on Step Over it stick for 2 times and then move at the end of method without error 
     {  
      public void run() 
      { 
       // update UI code 
      } 
     }); 
    } 
} 

Answer 1

試試這樣：

首先創建一個Handler：

Handler mHandler = new Handler(); 

改變這一狀況，

public void commentBuilder() 
    { 
     runOnUiThread(new Runnable() // while debugging, it comes here, on Step Over it stick for 2 times and then move at the end of method without error 
     {  
      public void run() 
      { 
       // update UI code 
      } 
     }); 
    } 

有了，

public void commentBuilder() 
    { 
     new Thread(new Runnable() { 
      @Override 
      public void run() { 
       // TODO Auto-generated method stub 
       while (isRunning) { 
        try { 
         // Thread.sleep(10000); 
         mHandler.post(new Runnable() { 

          @Override 
          public void run() { 
           // TODO Auto-generated method stub 
           // Write your code here to update the UI.        
          } 
         }); 
        } catch (Exception e) { 
         // TODO: handle exception 
        } 
       } 
      } 
     }).start(); 
    } 

停止線程通過這一次你與UI做，

isRunning = false; 

編輯：

嘗試使用異步任務是這樣的：

class parseComments extends AsyncTask<String, Integer,String> 
    { 
     protected String doInBackground(String... params) { 
      String parseComReturn = parseComments(); 
      return parseComReturn; 
     } 

     protected void onPostExecute(String result) { 
      if(result.equals("end")) 
      { 
       commentBuilder(); 
      } 
     } 
    } 

感謝。

Answer 2

runOnUiThread是Activity的方法，AsyncTask沒有提及活動。

但是，AsyncTask已經在UI線程上運行，並被設計爲完成該操作。

只處理onPostExecute中的UI更改。