In my app user can insert multiple location and show in map. How can i achieve this? I know how to draw route between two location but i want to draw route between multiple marker as like image. 
In image marker show location that is entered by user. I also want to calculate distance between marker like calculate distance between B to C and C to D.
How can I achieve this??
Use direction api which return multi-part directions using a series of waypoints.
private static final LatLng LOWER_MANHATTAN = new LatLng(40.722543,-73.998585);
private static final LatLng BROOKLYN_BRIDGE = new LatLng(40.7057, -73.9964);
private static final LatLng WALL_STREET = new LatLng(40.7064, -74.0094);
private String getMapsApiDirectionsUrl() {
String origin = "origin=" + LOWER_MANHATTAN.latitude + "," + LOWER_MANHATTAN.longitude;
String waypoints = "waypoints=optimize:true|" + BROOKLYN_BRIDGE.latitude + "," + BROOKLYN_BRIDGE.longitude + "|";
String destination = "destination=" + WALL_STREET.latitude + "," + WALL_STREET.longitude;
String sensor = "sensor=false";
String params = origin + "&" + waypoints + "&" + destination + "&" + sensor;
String output = "json";
String url = "https://maps.googleapis.com/maps/api/directions/"
+ output + "?" + params;
return url;
}
}
When you get response from above request . you need to draw route from response
public void drawRoute(String result) {
try {
//Tranform the string into a json object
final JSONObject json = new JSONObject(result);
JSONArray routeArray = json.getJSONArray("routes");
JSONObject routes = routeArray.getJSONObject(0);
JSONObject overviewPolylines = routes.getJSONObject("overview_polyline");
String encodedString = overviewPolylines.getString("points");
List<LatLng> list = decodePoly(encodedString);
Polyline line = mMap.addPolyline(new PolylineOptions()
.addAll(list)
.width(12)
.color(Color.parseColor("#05b1fb"))//Google maps blue color
.geodesic(true)
);
} catch (JSONException e) {
}
}
You will get more detail of this from Draw-route-github
For Distance calculation you need to Distance Matrix API is a service that provides travel distance and time for a matrix of origins and destinations
Using direction api you can achieve this. you just have to pass user inserted marker as waypoints as follow
https://maps.googleapis.com/maps/api/directions/json?
origin=sydney,au&destination=perth,au
&waypoints=via:-37.81223%2C144.96254%7Cvia:-34.92788%2C138.60008
&key=YOUR_API_KEY
you will get list of route which have the distance between to points
//retrofit
@GET("https://maps.googleapis.com/maps/api/directions/json")
Observable<DirectionResults> getDirectionWithWayPoints(@Query("origin") String origin, @Query("destination") String destination, @Query("waypoints") String wayPoints, @Query("key") String key);
// plotting logic
api.getDirectionWithWayPoints(startPoint, endPoint, stringBuilder.toString(), getString(R.string.API_KEY))
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribeWith(new Observer<DirectionResults>() {
@Override
public void onSubscribe(Disposable d) {
}
@Override
public void onNext(DirectionResults directionResults) {
hideDialog();
if (null == directionResults) {
return;
}
ArrayList<LatLng> routelist = new ArrayList<>();
routelist.add(latLngStart);
if (directionResults.getRoutes().size() > 0) {
List<LatLng> decodelist;
RoutesItem routeA = directionResults.getRoutes().get(0);
if (routeA.getLegs().size() > 0) {
for (int j = 0; j < routeA.getLegs().size(); j++) {
List<StepsItem> steps = routeA.getLegs().get(j).getSteps();
StepsItem step;
Location location;
String polyline;
for (int i = 0; i < steps.size(); i++) {
step = steps.get(i);
polyline = step.getPolyline().getPoints();
decodelist = DirectionsJSONParser.decodePoly(polyline);
routelist.addAll(decodelist);
}
}
}
}
if (routelist.size() > 0) {
routelist.add(latLngEnd);
rectLine = new PolylineOptions().width(12).color(
Color.CYAN);
for (int i = 0; i < routelist.size(); i++) {
rectLine.add(routelist.get(i));
}
// Adding route on the map
if (null != mMap) {
mMap.addPolyline(rectLine);
fixZoom(rectLine, mMap);
getVehicleId();
}
}
}
@Override
public void onError(Throwable e) {
hideDialog();
e.printStackTrace();
}
@Override
public void onComplete() {
}
});
}
}
Google provides libraries out of the box for solving this kind of issues.
I would structure my application in following manner.
Use google API's, you will need more than 1 API to achieve both of the tasks.
2.a To find out distances between two points use Google Distance Matrix API (https://developers.google.com/maps/documentation/distance-matrix/start).
2.b To add multiple markers you can refer to following answer Google Maps JS API v3 - Simple Multiple Marker Example
For draw route you can use :
PolylineOptions options = new
PolylineOptions().width(5).color(Color.BLUE).geodesic(true);
for (int z = 0; z < list.size(); z++) {
LatLng point = list.get(z);
options.add(point);
}
line = myMap.addPolyline(options);
And calculating distance for usimg **Google Maps Direction API**
