Xutils请求服务器json数据与下载文件

String code_url = "https://ic.snssdk.com/user/mobile/send_code/v2/";

                            HttpUtils httpUtils = new HttpUtils();
                            //网址
                            RequestParams params = new RequestParams();
                            params.addBodyParameter("type", "1");// 必填
                            params.addBodyParameter("mobile",shoujihao );// 必填

                            httpUtils.send(HttpMethod.POST, code_url, params,
                                    new RequestCallBack<String>() {

                                @Override
                                public void onStart() {
                                    // TODO Auto-generated method stub
                                    super.onStart();
                                    Log.i("TAG", "请求开始");
                                }

                                @Override
                                public void onFailure(HttpException arg0, String arg1) {

                                    Log.i("TAG", "发送验证码请求失败:  " + arg1);
                                    Toast.makeText(PhoneZhuCe.this, "发送验证码请求失败:  "+ arg1, 0).show();
                                }

                                @Override
                                public void onSuccess(ResponseInfo<String> arg0) {
                                    Log.i("TAG", "发送验证码请求成功:  " + arg0.result);

                                    String s=arg0.result;
                                    Gson gson=new Gson();
                                    Loginphone fromJson = gson.fromJson(s, Loginphone.class);
                                    String message = fromJson.getMessage();
                                    if(message.equals("success")){
                                        Intent intent = new Intent(PhoneZhuCe.this,
                                                PhoneZhuCe2.class);

                                        startActivity(intent);
                                    }else{
                                        Toast.makeText(PhoneZhuCe.this, fromJson.getData().getDescription(), 0)
                                                .show();
                                    }

                                }
                            });

下载数据：

String path = Environment.getExternalStorageDirectory().getPath();
    String target=path+"/image/"+num+".png";//下载文件保存的路径

    HttpUtils http=new HttpUtils();
   //url路径
    HttpHandler handler=http.download(url, target, true, true,new RequestCallBack<File>() {

        @Override
        public void onSuccess(ResponseInfo<File> arg0) {
            // TODO Auto-generated method stub

        }

        @Override
        public void onFailure(HttpException arg0, String arg1) {
            // TODO Auto-generated method stub

        }
    });