2017-09-14 189 views
0

我有一個應用程序從我的網站訪問一些JSON數據。該應用在我的手機和我測試的手機上的WIFI和移動數據上工作正常。但是,一些用戶在移動數據上遇到問題。當他們使用WIFI時,它可以正常工作,但不適用於他們的移動數據。Android JSON makeHttpRequest在移動數據上返回null

下面是獲取json數據的代碼。

 List<NameValuePair> params = new ArrayList<NameValuePair>(); 
     // getting JSON string from url 
     JSONObject json = jParser.makeHttpRequest(url, "GET", params); 

看來json的手機上的移動數據返回null。我不知道爲什麼。

這裏的類的JSON解析器

public class JSONParser { 

static InputStream is = null; 
static JSONObject jObj = null; 
static String json = ""; 

// constructor 
public JSONParser() { 

} 

// function get json from url 
// by making HTTP POST or GET mehtod 
public JSONObject makeHttpRequest(String url, String method, 
     List<NameValuePair> params) { 

    // Making HTTP request 
    try { 

     // check for request method 
     if(method == "POST"){ 
      // request method is POST 
      // defaultHttpClient 
      DefaultHttpClient httpClient = new DefaultHttpClient(); 
      HttpPost httpPost = new HttpPost(url); 
      httpPost.setEntity(new UrlEncodedFormEntity(params)); 

      HttpResponse httpResponse = httpClient.execute(httpPost); 
      HttpEntity httpEntity = httpResponse.getEntity(); 
      is = httpEntity.getContent(); 

     }else if(method == "GET"){ 
      // request method is GET 
      DefaultHttpClient httpClient = new DefaultHttpClient(); 
      // String paramString = URLEncodedUtils.format(params, "utf-8"); 
      // url += "?" + paramString; 
      HttpGet httpGet = new HttpGet(url); 

      HttpResponse httpResponse = httpClient.execute(httpGet); 
      HttpEntity httpEntity = httpResponse.getEntity(); 
      is = httpEntity.getContent(); 
     }   

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

    try { 
     BufferedReader reader = new BufferedReader(new InputStreamReader(
       is, "iso-8859-1"), 8); 
     StringBuilder sb = new StringBuilder(); 
     String line = null; 
     while ((line = reader.readLine()) != null) { 
      sb.append(line + "\n"); 
     } 
     is.close(); 
     json = sb.toString(); 
    } catch (Exception e) { 
     Log.e("Buffer Error", "Error converting result " + e.toString()); 
    } 

    // try parse the string to a JSON object 
    try { 
     jObj = new JSONObject(json); 
    } catch (JSONException e) { 
     Log.e("JSON Parser", "Error parsing data " + e.toString()); 
    } 

    // return JSON String 
    return jObj; 

} 
} 
+0

我認爲當你使用移動數據,您的應用程序需要一定的時間要求服務器。您可以從服務器初始化接口等待響應。 – Dungnbhut

+0

使用此答案爲api請求https://stackoverflow.com/questions/46086118/getting-json-info-from-php-to-android-studio?answertab=votes#tab-top –

回答

0

嘗試設置連接插座超時,以合理的時間 - 在景區裏的數據連接是爲了有點慢測試您的設備上以確定應該有多長時間。

這裏是一個偉大SO與如何做到這一點的例子回答: https://stackoverflow.com/a/1565243/5095571