Question

我需要从JSON网址检索一些值。下面的代码我尝试过，但是它没有给出任何错误或异常，但没有获取值。

RequestQueue queue = Volley.newRequestQueue(this);
String url ="http://api.ipstack.com/111.125.204.140? 
access_key=############";

StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
        new Response.Listener<String>() {
            @Override
            public void onResponse(String response) {

                JSONObject json = null;
                try {
                    json = new JSONObject(response);
                } catch (JSONException e) {
                    e.printStackTrace();
                    Log.d("errror",e.toString());// Not getting any error
                }

                String cityName = json.optString("type");// here iam not getting any value.
                txtJson.setText(cityName);

            }
        }, new Response.ErrorListener() {
    @Override
    public void onErrorResponse(VolleyError error) {
        txtJson.setText("That didn't work!");
    }
});

queue.add(stringRequest);

JSON结构

{
"ip": "134.201.250.155",
"hostname": "134.201.250.155",
"type": "ipv4",
"continent_code": "NA",
  "continent_name": "North America",
"country_code": "US",
"country_name": "United States",
"region_code": "CA",
"region_name": "California",
"city": "Los Angeles",
 "zip": "90013",
 "latitude": 34.0453,
 "longitude": -118.2413
  }

我正在寻找过去2周内的解决方案。请任何人对此帮助我，将不胜感激。提前致谢。

Answer 1

尝试JSONobject

RequestQueue queue = Volley.newRequestQueue(this);
String url = "http://api.ipstack.com/111.125.204.140? 
access_key = ############";

StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
  new Response.Listener < String > () {
    @Override
    public void onResponse(String response) {

      JSONObject json = null;
      try {
        json = new JSONObject(response);
      } catch (JSONException e) {
        e.printStackTrace();
        Log.d("errror", e.toString()); // Not getting any error
      }

      /* try this instead */
      JSONObject json = new JSONObject(response);
      String cityName = json.getString("city");



    }
  }, new Response.ErrorListener() {
    @Override
    public void onErrorResponse(VolleyError error) {
      txtJson.setText("That didn't work!");
    }
  });

queue.add(stringRequest);

Answer 2

尝试下面的代码

RequestQueue queue = Volley.newRequestQueue(this);
    String url ="http://api.ipstack.com/111.125.204.140?
    access_key=############";

    StringRequest stringRequest = new StringRequest(Request.Method.GET, url,
            new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {

                    JSONObject json = null;
                    try {
                        json = new JSONObject(response);
                        if (json.has("type") && !json.isNull("type")) {
                            String cityName = json.getString("type");
                            txtJson.setText(cityName);
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                        Log.d("errror",e.toString());// Not getting any error
                    }



                }
            }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            txtJson.setText("That didn't work!");
        }
    });

    queue.add(stringRequest);

使用Android中的Volley库从URL解析JSON

2 个答案: