在android中解析对象的JSON数组 [英] Parsing JSON array of objects in android

问题描述

我想从这个 api 调用中获取 lineId、destinationName 和 timeToStation https://api.tfl.gov.uk/Line/25,86,w19/Arrivals?stopPointId=490009219W&app_id=&app_key=有人可以帮忙举个例子吗?[{"$type": "Tfl.Api.Presentation.Entities.Prediction, Tfl.Api.Presentation.Entities","id": "-480785385",操作类型":1，"vehicleId": "BJ11DSX","naptanId": "490009219W","stationName": "小伊尔福德巷","lineId": "25","lineName": "25","平台名称": "B","direction": "入站","轴承": "245","destinationNaptanId": "","destinationName": "牛津马戏团","时间戳": "2016-04-17T16:56:56.463Z",时间到站":1534，当前位置": ""，"towards": "East Ham or Manor Park","expectedArrival": "2016-04-17T17:22:31Z","timeToLive": "2016-04-17T17:23:01Z","modeName": "总线"},{"$type": "Tfl.Api.Presentation.Entities.Prediction, Tfl.Api.Presentation.Entities","id": "1992301652",操作类型":1，"vehicleId": "BJ11DVA","naptanId": "490009219W","stationName": "小伊尔福德巷","lineId": "25","lineName": "25","平台名称": "B","direction": "入站","轴承": "245","destinationNaptanId": "","destinationName": "牛津马戏团","时间戳": "2016-04-17T16:56:56.463Z",时间到站":1159，当前位置": ""，"towards": "East Ham or Manor Park","expectedArrival": "2016-04-17T17:16:16Z","timeToLive": "2016-04-17T17:16:46Z","modeName": "总线"},{"$type": "Tfl.Api.Presentation.Entities.Prediction, Tfl.Api.Presentation.Entities","id": "733078946",操作类型":1，"vehicleId": "BJ11DVG","naptanId": "490009219W","stationName": "小伊尔福德巷","lineId": "25","lineName": "25",平台名称":B"，"direction": "入站","轴承": "245","destinationNaptanId": "","destinationName": "牛津马戏团","时间戳": "2016-04-17T16:56:56.463Z",时间到站":790，当前位置": ""，"towards": "East Ham or Manor Park","expectedArrival": "2016-04-17T17:10:07Z","timeToLive": "2016-04-17T17:10:37Z","modeName": "总线"}]

I want to get the lineId, destinationName and timeToStation from this api call https://api.tfl.gov.uk/Line/25,86,w19/Arrivals?stopPointId=490009219W&app_id=&app_key= Can someone help with example please? [ { "$type": "Tfl.Api.Presentation.Entities.Prediction, Tfl.Api.Presentation.Entities", "id": "-480785385", "operationType": 1, "vehicleId": "BJ11DSX", "naptanId": "490009219W", "stationName": "Little Ilford Lane", "lineId": "25", "lineName": "25", "platformName": "B", "direction": "inbound", "bearing": "245", "destinationNaptanId": "", "destinationName": "Oxford Circus", "timestamp": "2016-04-17T16:56:56.463Z", "timeToStation": 1534, "currentLocation": "", "towards": "East Ham or Manor Park", "expectedArrival": "2016-04-17T17:22:31Z", "timeToLive": "2016-04-17T17:23:01Z", "modeName": "bus" }, { "$type": "Tfl.Api.Presentation.Entities.Prediction, Tfl.Api.Presentation.Entities", "id": "1992301652", "operationType": 1, "vehicleId": "BJ11DVA", "naptanId": "490009219W", "stationName": "Little Ilford Lane", "lineId": "25", "lineName": "25", "platformName": "B", "direction": "inbound", "bearing": "245", "destinationNaptanId": "", "destinationName": "Oxford Circus", "timestamp": "2016-04-17T16:56:56.463Z", "timeToStation": 1159, "currentLocation": "", "towards": "East Ham or Manor Park", "expectedArrival": "2016-04-17T17:16:16Z", "timeToLive": "2016-04-17T17:16:46Z", "modeName": "bus" }, { "$type": "Tfl.Api.Presentation.Entities.Prediction, Tfl.Api.Presentation.Entities", "id": "733078946", "operationType": 1, "vehicleId": "BJ11DVG", "naptanId": "490009219W", "stationName": "Little Ilford Lane", "lineId": "25", "lineName": "25", "platformName": "B", "direction": "inbound", "bearing": "245", "destinationNaptanId": "", "destinationName": "Oxford Circus", "timestamp": "2016-04-17T16:56:56.463Z", "timeToStation": 790, "currentLocation": "", "towards": "East Ham or Manor Park", "expectedArrival": "2016-04-17T17:10:07Z", "timeToLive": "2016-04-17T17:10:37Z", "modeName": "bus" } ]

我的 AsyncTask 被赋予了 belw

My AsyncTask is given belw

   @Override
    protected JSONObject doInBackground(String... args){
       JSONParser jsonParser = new JSONParser();

        Log.i("URL", url);
        JSONObject json = jsonParser.getJSONFromUrl(url);
        if(json == null) {
            Log.i("Json obj =" , "NULL");
        }
        else{
            return json;
        }
        return new JSONObject();
    }

    @Override
    protected void onPostExecute(JSONObject json){
        progressDialog.dismiss();
        //String shopName ="";
       // String distance="";

        try{
            //Fetching JSON Array
            Log.i("JSON", json.toString());

            jsonData = new JSONArray(json);

            Double arrivalTime= 0.0;

            for(int i=0;i<json.length();i++) {

                try {
                    JSONObject c = json.getJSONObject(i);

                    busNoArray.add(json.getString(TAG_LINEID));
                    destinationArray.add(json.getString(TAG_DESTINATION));

                    arrivalTime = json.getDouble(TAG_TIME) / 60;
                    arrivalTimeArray.add(arrivalTime);

                } catch (JSONException e) {
                    e.printStackTrace();
                }

            }

            adapter = new BusTimeAdapter(BusTimeActivity.this,busNoArray, destinationArray, arrivalTimeArray);
            mListView.setAdapter(adapter);`

有人可以帮我吗?

推荐答案

首先确保您已检索到 JSON String，

First be sure you have retrieved JSON String,

然后你可以很容易地访问它们里面的属性

Then You can easily access the properties inside them like

try {
     JSONArray jsonArray = new JSONArray(json);
     JSONObject obj = jsonArray.getJSONObject(0); //0 for just retrieving first object you can loop it
     String myVehicleID = obj.getString("vehicleId"); //To retrieve vehicleId
     //Similarly do it for others as well
    } catch (JSONException e) {
      e.printStackTrace();
    }

这篇关于在android中解析对象的JSON数组的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！