如何通過HTTP檢索網站？

Question

我有這個應用程序強制關閉此代碼，我做錯了什麼？

public void buscaAno(View v){ 

    HttpClient httpclient = new DefaultHttpClient(); 
    HttpPost httppost = new HttpPost("http://sapires.netne.net/teste.php?formato=json&idade=55"); 
    try { 
     HttpResponse response = httpclient.execute(httppost); 
     final String str = EntityUtils.toString(response.getEntity()); 

     TextView tv = (TextView) findViewById(R.id.idade); 
     tv.setText(str); 
    } 
    catch (IOException e) { 
     // TODO Auto-generated catch block 
     e.printStackTrace(); 
    } 

} 

Answer 1

看起來這是onClick監聽器，它在主線程上執行阻塞操作，進而導致ANR或NetworkOnMainThreadException。您應該使用AsyncTask或Service爲您的目的。

例如，你可以擴展的AsyncTask方式如下：

private class PostRequestTask extends AsyncTask<String, Void, String> { 
     protected String doInBackground(String... strings) { 
      HttpClient httpclient = new DefaultHttpClient(); 
      HttpPost httppost = new HttpPost(strings[0]); 

      try { 
       HttpResponse response = httpclient.execute(httppost); 
       return EntityUtils.toString(response.getEntity()); 
      } catch (IOException e) { 
       //Handle exception here 
      } 
     } 

     protected void onPostExecute(String result) { 
      TextView textView = (TextView) findViewById(R.id.idade); 
      textView.setText(result); 
     } 
    } 

，然後用它是這樣的：

public void buscaAno(View v) { 
     new PostRequestTask().execute("http://sapires.netne.net/teste.php?formato=json&idade=55"); 
    }