谷歌地图API中的Android应用程序JSON解析 [英] JSON parsing of Google Maps API in Android App
问题描述
我想使用谷歌地图API来获取方向的时间。我希望创建一个URL，得到JSON响应，然后检查行程持续时间响应。当我创建JSON对象，我有麻烦浏览它。对我来说，这表明我要么搞砸得到响应或导航JSON对象。我倒是AP preciate如果你能偷看我从各地的网络教程缝合在一起位和code片。
这code的目的是获得响应。它的周围有一个try / catch，也没有引发任何错误。
字符串stringUrl =＆LT; URL GOES HERE取代;
网址URL =新的URL（stringUrl）;
HttpURLConnection的httpconn =（HttpURLConnection类）url.openConnection（）;
如果（httpconn.getResponse code（）== HttpURLConnection.HTTP_OK）
{
BufferedReader中输入=新的BufferedReader（新的InputStreamReader（httpconn.getInputStream（）），8192）;
字符串strLine中= NULL;
而（（strLine中= input.readLine（））！= NULL）
{
response.append（strLine中）;
}
input.close（）;
}
串jsonOutput = response.toString（）;
这code旨在采取输出和解析成最后一个字符串，持续时间，灵感来自<一href="http://stackoverflow.com/questions/2951007/android-get-duration-from-maps-google-com-directions/2953077#2953077"标题=这个计算器的答案>这个计算器回答了类似的问题。
的JSONObject的JSONObject =新的JSONObject（jsonOutput）;
JSONObject的routeObject = jsonObject.getJSONObject（路）;
JSONObject的legsObject = routeObject.getJSONObject（腿）;
JSONObject的durationObject = legsObject.getJSONObject（期限）;
字符串长度= durationObject.getString（文字）;
我赶上第二块的第二行的JSON异常。任何人都可以帮助解决这一问题？或者提出一个简单的方法来获得相同的数据？
编辑：多亏了这里的第一个有用的答案（来自aromero），后半部分现在看起来像：
的JSONObject的JSONObject =新的JSONObject（responseText的）;
JSONArray routeObject = jsonObject.getJSONArray（路）;
JSONArray legsObject = routeObject.getJSONArray（2）; ***错误***
的JSONObject durationObject = legsObject.getJSONObject（1）;
字符串长度= durationObject.getString（文字）;
但它仍然抛出一个JSON例外，只是现在它的第三个行之后。我敢肯定，这是令人尴尬容易解决，但我真的AP preciate一些帮助。
为例JSON文件的相关部分如下所示：
{
路线：
{
界限：{
东北 ： {
纬度：34.092810，
液化天然气：-118.328860
}，
西南 ： {
纬度：33.995590，
液化天然气：-118.446040
}
}，
版权：地图数据©2011谷歌，
腿：
{
距离 ： {
文：12.9英里，
值：20807
}，
持续时间：{
文：27分钟，
值：1619
}，
路线而不是使用数组， getJSONObject ，使用 getJSONArray
腿是一个数组也。
的JSONObject的JSONObject =新的JSONObject（responseText的）;
// routesArray包含所有路线
JSONArray routesArray = jsonObject.getJSONArray（路）;
//取得第一路线
JSONObject的路线= routesArray.getJSONObject（0）;
//采取一切腿路线
JSONArray腿= route.getJSONArray（腿）;
//取得首回合
的JSONObject腿= legs.getJSONObject（0）;
JSONObject的durationObject = leg.getJSONObject（期限）;
字符串长度= durationObject.getString（文字）;
I'm trying to use the google maps API to fetch direction times. I'm hoping to create a url, get the JSON response, and then examine that response for travel duration. After I create the JSON object, I have trouble navigating it. To me, this indicates that I have either messed up getting the response or navigating the JSON object. I'd appreciate it if you could peek at the bits and pieces of code I have stitched together from tutorials around the web.
This code is intended to get the response. It's surrounded by a try/catch and it hasn't triggered any errors.
String stringUrl = <URL GOES HERE>;
URL url = new URL(stringUrl);
HttpURLConnection httpconn = (HttpURLConnection)url.openConnection();
if (httpconn.getResponseCode() == HttpURLConnection.HTTP_OK)
{
BufferedReader input = new BufferedReader(new InputStreamReader(httpconn.getInputStream()),8192);
String strLine = null;
while ((strLine = input.readLine()) != null)
{
response.append(strLine);
}
input.close();
}
String jsonOutput = response.toString();
This code is intended to take that output and parse it into the final string, duration, as inspired by this stackoverflow answer for a similar question.
JSONObject jsonObject = new JSONObject(jsonOutput);
JSONObject routeObject = jsonObject.getJSONObject("routes");
JSONObject legsObject = routeObject.getJSONObject("legs");
JSONObject durationObject = legsObject.getJSONObject("duration");
String duration = durationObject.getString("text");
I'm catching a JSON exception on the second line of the second block. Can anyone help to fix this? Or perhaps suggest a simpler way to get the same data?
EDIT: thanks to the first helpful answer here (from aromero), the latter half now looks like:
JSONObject jsonObject = new JSONObject(responseText);
JSONArray routeObject = jsonObject.getJSONArray("routes");
JSONArray legsObject = routeObject.getJSONArray(2); ***error***
JSONObject durationObject = legsObject.getJSONObject(1);
String duration = durationObject.getString("text");
But it is still throwing a JSON exception, only now it's after the third line. I'm sure this is embarrassingly easy to fix, but I would really appreciate some help.
The relevant part of an example JSON file is shown below:
{
"routes" : [
{
"bounds" : {
"northeast" : {
"lat" : 34.092810,
"lng" : -118.328860
},
"southwest" : {
"lat" : 33.995590,
"lng" : -118.446040
}
},
"copyrights" : "Map data ©2011 Google",
"legs" : [
{
"distance" : {
"text" : "12.9 mi",
"value" : 20807
},
"duration" : {
"text" : "27 mins",
"value" : 1619
},
"routes" is an array, instead of using getJSONObject, use getJSONArray
"legs" is an array also.
JSONObject jsonObject = new JSONObject(responseText);
// routesArray contains ALL routes
JSONArray routesArray = jsonObject.getJSONArray("routes");
// Grab the first route
JSONObject route = routesArray.getJSONObject(0);
// Take all legs from the route
JSONArray legs = route.getJSONArray("legs");
// Grab first leg
JSONObject leg = legs.getJSONObject(0);
JSONObject durationObject = leg.getJSONObject("duration");
String duration = durationObject.getString("text");
这篇关于谷歌地图API中的Android应用程序JSON解析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！
