使用Android应用程序从服务器中提取数据

Question

我在Android应用程序中从服务器中提取数据时遇到问题。加载数据需要很长时间，请注意它只有5行，我想在我的情况下，因为我在每个循环中拉动用户图片。我不知道更好的方法，有什么建议吗？

以下是我在后台函数中执行此操作的代码：

 protected ArrayList<User> doInBackground(Object... Void) {

        String response = performGetCall(SERVER_ADDRESS + "FetchAll.php", null);
        User user = null;
        ArrayList<User> listUsers = new ArrayList<User>();
        try {
            JSONArray allUsersData = new JSONArray(response);
            //list = ArrayUtil.convert(allUsersData);
            //Log.d("List", list.toString());
            for (int i=0, l=allUsersData.length(); i<l; i++) {
                JSONObject userData = allUsersData.getJSONObject(i);
                String imageName = userData.getString("imageName");
                Bitmap image = null;
                if (imageName != null) {
                    String imagePath = SERVER_ADDRESS + "pictuers/" + imageName;
                    HttpURLConnection conn = null;
                    try {
                        URL imageUrl = new URL(imagePath);
                        conn = (HttpURLConnection) imageUrl.openConnection();
                        conn.setReadTimeout(CONNECTION_TIMEOUT);
                        conn.setConnectTimeout(CONNECTION_TIMEOUT);
                        image = BitmapFactory.decodeStream((InputStream) conn.getContent(), null, null);
                    } catch (IOException e) {
                        Log.d("Image get exception:",e.toString());
                        e.printStackTrace();
                        image = null;
                    }
                }else {
                    imageName = "";
                }


                user = new User(userData.getInt("user_id"), userData.getString("name"), userData.getString("userName"), userData.getString("email"),userData.getString("gender"),userData.getString("password"),userData.getString("phone"), imageName,image);
                    listUsers.add(user);
                    // Log.d("Rturned User: ",returnedUser.email);
                    //Log.d("Response", userData.toString());
            }
            return listUsers;
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return listUsers;

    }