【发布时间】：2016-08-09 08:07:37
【问题描述】：
我想从这个 api 调用https://api.tfl.gov.uk/Line/25,86,w19/Arrivals?stopPointId=490009219W&app_id=&app_key= 中获取 lineId、destinationName 和 timeToStation
有人可以帮忙举个例子吗？
[
{
"$type": "Tfl.Api.Presentation.Entities.Prediction, Tfl.Api.Presentation.Entities",
"id": "-480785385",
"operationType": 1,
"vehicleId": "BJ11DSX",
"naptanId": "490009219W",
"stationName": "Little Ilford Lane",
"lineId": "25",
"lineName": "25",
"platformName": "B",
"direction": "inbound",
"bearing": "245",
"destinationNaptanId": "",
"destinationName": "Oxford Circus",
"timestamp": "2016-04-17T16:56:56.463Z",
"timeToStation": 1534,
"currentLocation": "",
"towards": "East Ham or Manor Park",
"expectedArrival": "2016-04-17T17:22:31Z",
"timeToLive": "2016-04-17T17:23:01Z",
"modeName": "bus"
},
{
"$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 在下面给出
@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？
【问题讨论】：
-
你确定这是你的 json
Log.i("JSON", json.toString());记录吗？你做错了一切。 -
这只是为了确保它不是空响应。我不明白的是如何访问数组内的对象，因为我的 doInBackground 返回一个对象，我不确定如何访问数组内的值。
-
我已将其添加为答案，我使用 0 仅检索第一个对象，但您也可以循环检索其他对象。并添加了一些 cmets 来澄清这些。希望对您有所帮助。如果您有任何困惑，请随时询问。