AsyncTask只能第一次工作

Question

我想做一个实用程序httpClient类

我的代码很好的执行第一次。在调试时，第二个执行不会进入或执行，所以有些东西被搞乱了。

的活动/监听

protected String getPage(String url, List<NameValuePair> namevaluePairs, String postOrGet, Activity whichActivity, String dialogText) { 
    try { 
     httpHelper.setListValues(namevaluePairs); 
     httpHelper.setPostOrGet(postOrGet); 
     httpHelper.setParentActivity(whichActivity); 
     httpHelper.setDialogText(dialogText); 
     httpHelper.execute(url); 
    } catch (Exception e) { 
     e.printStackTrace(); 
    } 
    return resultHTML; 
} 

实用类：

public class HTTPHelper extends AsyncTask<String, Void, Void> { 
    private String resultString; 
    private HttpClient httpclient; 
    private List<NameValuePair> nameValuePairs; 
    private String postOrGet; 
    private Activity parentActivity; 
    private String Error; 
    private String dialogText; 
    private ProgressDialog Dialog; 
    WebServiceListener listener; 

    public HTTPHelper(WebServiceListener listener) { 
     this.listener = listener; 
     Error = null; 
     httpclient = new DefaultHttpClient(); 
     postOrGet = "get"; 
     nameValuePairs = null; 
     dialogText = "Logging in"; 
    } 

    @Override 
    public void onPreExecute() { 
     super.onPreExecute(); 
     Error = null; 
     Dialog.setMessage(dialogText); 
     Dialog.show(); 
    } 

    @Override 
    public void onPostExecute(Void unused) { 
     Dialog.dismiss(); 
     if (Error != null) { 
      Toast.makeText(parentActivity, Error, Toast.LENGTH_LONG).show(); 
     } else { 
      ArrayList<String> myList = new ArrayList<String>(); 
      myList.add(resultString); 
      listener.onHTTPGetComplete(myList); 
     } 
    } 

    public void setDialogText(String txt) { 
     dialogText = txt; 
    } 

    public void setListValues(List<NameValuePair> incNameValuePairs) { 
     nameValuePairs = incNameValuePairs; 
    } 

    public void setPostOrGet(String pOrG) { 
     postOrGet = pOrG; 
    } 

    public void setParentActivity(Activity myAct) { 
     parentActivity = myAct; 
     Dialog = new ProgressDialog(parentActivity); 
    } 

    @Override 
    protected Void doInBackground(String... urls) { 
     BufferedReader in = null; 
     try { 
      HttpGet httpget = new HttpGet(urls[0]); 
      HttpPost httppost = new HttpPost(urls[0]); 
      HttpResponse response = null; 

      if (postOrGet.toLowerCase().contains("post")) { 
       httppost.setHeader("Content-Type", "application/x-www-form-urlencoded"); 
       try { 
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs, HTTP.UTF_8)); 
        response = httpclient.execute(httppost); 
       } catch (IOException e) { 
        e.printStackTrace(); 
       } 
      } else { 
       try { 
        response = httpclient.execute(httpget); 
       } catch (IOException e) { 
        e.printStackTrace(); 
       } 
      } 
      try { 
       in = new BufferedReader(new InputStreamReader(response.getEntity().getContent())); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 

      StringBuffer sb = new StringBuffer(""); 
      String line = ""; 
      String NL = System.getProperty("line.separator"); 
      try { 
       while ((line = in.readLine()) != null) { 
        sb.append(line + NL); 
       } 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 

      try { 
       in.close(); 
      } catch (IOException e) { 
       e.printStackTrace(); 
      } 
      resultString = sb.toString(); 
      return null; 
     } finally { 
     } 
    } 
} 

Answer 1

一个的AsyncTask只能使用一次，如文档中陈述运行：http://developer.android.com/reference/android/os/AsyncTask.html

因此，对于每一个请求，你需要创建一个新的帮助对象。

编辑：

检查了这一点：ThreadSafeClientConnManager

Answer 2

（你的情况HTTPHelper）创建AsyncTask的新实例每次执行它时。