Take Coordinates from json and search on Google map (Android)

Question

I am developing a map application on Android which is about finding best roads. The problem is not all roads name are on Google API so i have it on one JSon file. Which is the best way to get coordinates from JSon file and show it to Android App with lines from position A to B.

    {
   "type": "FeatureCollection",
   "crs": {
      "type": "name",
      "properties": {
         "name": "urn:ogc:def:crs:OGC:1.3:CRS84"
      }
   },
   "features": [
      {
         "type": "Feature",
         "properties": {
            "Name": "po",
            "description": "",
            "timestamp": null,
            "begin": null,
            "end": null,
            "altitudeMode": null,
            "tessellate": -1,
            "extrude": 0,
            "visibility": -1,
            "drawOrder": null,
            "icon": null,
            "description_1": null,
            "Number": "10",
            "RoadNameCo": "03_10234",
            "RoadNameAL": "MEHDI HOXHA"
         },
         "geometry": {
            "type": "Point",
            "coordinates": [
               20.853835,
               42.601668,
               0
            ]
         }
      },
      {
         "type": "Feature",
         "properties": {
            "Name": "po",
            "description": "",
            "timestamp": null,
            "begin": null,
            "end": null,
            "altitudeMode": null,
            "tessellate": -1,
            "extrude": 0,
            "visibility": -1,
            "drawOrder": null,
            "icon": null,
            "description_1": null,
            "Number": "16",
            "RoadNameCo": "03_10234",
            "RoadNameAL": "MEHDI HOXHA"
         },
         "geometry": {
            "type": "Point",
            "coordinates": [
               20.854006,
               42.60127,
               0
            ]
         }
      }

   ]
}

what exactly is a problem? you can't parse JSON, or you can't do route on the map? That are 2 different questions, each of which was answered here already for few hundred times. — Vladyslav Matviienko, Sep 21 '17 at 07:17
you can't parse JSON to google map. As I said, that are 2 different questions. First parse JSON to coordinates, then set coordinates to google map. So what of 2 **different and completely unrelated** tasks is your question? — Vladyslav Matviienko, Sep 21 '17 at 07:20
Alright thanks or your help. How do l parse JSON to coordinates? — MeliDev, Sep 21 '17 at 07:24
`each of which was answered here already for few hundred times` - search for `Android parse json`, you will find 100+ answers — Vladyslav Matviienko, Sep 21 '17 at 07:26
Not sure if this is an answer, but [check this out.](https://www.youtube.com/watch?v=CCZPUeY94MU) Its a tutorial to find road and add polylines on road. I tried and I can assure you it is working. If you want to know how it works (demo), check out [this part of video](https://youtu.be/CCZPUeY94MU?t=1447). It have English subtitles — Aswin P Ashok, Sep 21 '17 at 08:08
@AswinPAshok thanks for help, the polyines part is OK but the coordinates lat long taking from json dont know? — MeliDev, Sep 21 '17 at 08:11
So you just want the `"coordinates": [20.854006,42.60127,0]` out of that object? and store that in an array? — Aswin P Ashok, Sep 21 '17 at 09:02
do you want that 0 in array? I can write a function which return a list of LatLng objects from the string given without 0. — Aswin P Ashok, Sep 21 '17 at 09:50

score 1 · Answer 1 · edited Sep 21 '17 at 09:35

1

Just try to parse like this:

JSONArray lat_long_jsonArray = jsonObject.getJSONArray("coordinates");
if (lat_long_jsonArray.length() != 0)
{

  String Longitude(lat_long_jsonArray.get(0).toString());

  String Latitude(lat_long_jsonArray.get(1).toString());
}

edited Sep 21 '17 at 09:35

Miriam Farber

18,986
14
61
76

answered Sep 21 '17 at 07:26

yash786

1,151
8
18

please check your code, it won't compile – Vladyslav Matviienko Sep 21 '17 at 07:32
@VladMatvienko I have given you only how to get co-ordinates form coordinates JsonArray now you have to parse. – yash786 Sep 21 '17 at 07:34
That was not me who asked the questions, but your code is invalid. Please double check Lat and Long declaration, or usage, or whatever it should be, it is not clear. – Vladyslav Matviienko Sep 21 '17 at 07:35
@MuharremSmakiqi, excuse me, I don't think I want one. – Vladyslav Matviienko Sep 21 '17 at 08:57

Aswin P Ashok · Accepted Answer · 2017-09-21T10:53:31.670

Try this

private List<LatLng> getLocationList(String JSON_String)
{
   List<LatLng> locationList = new ArrayList<>();
    try {

        JSONObject object = new JSONObject(JSON_String);
        JSONArray mArray = object.getJSONArray("features");

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

            JSONObject obj=mArray.getJSONObject(i);
            JSONObject geometryObject=obj.getJSONObject("geometry");
            JSONArray locationJSON_Array=geometryObject.getJSONArray("coordinates");

            LatLng location=new LatLng(locationJSON_Array.getDouble(0),locationJSON_Array.getDouble(1));
            locationList.add(location);
        }

    }catch (JSONException ex){
        ex.printStackTrace();
        //handle Exception
    } 
    return locationList;
}

Use it like this

List<LatLng> LocationList =getLocationList(Your_JSON_String);//The String posted in question
LatLng firstLocation=locationList.get(0);
LatLng secondLocation=locationList.get(1);

Let me Know if anything goes wrong

Take Coordinates from json and search on Google map (Android)

2 Answers2