Develop Reference

How do I retrieve the JSON response for each click on Google Map Marker?

I was able to make multiple marks on the google map on android by getting data from JSON. So NOW each of those markers has their own corresponding bukken_name, latitute and longitude.
Each time I click a specific marker on the map. I want it to display in console their retrieved JSON data.
In my current code, onMarkerClick gets the values and then displays it in System.out.println. But whenever I do so click the marker it only keeps on display the exact same value of the last JSON data.
StringRequest stringRequest = new StringRequest(url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try{
JSONObject jsonObject = new JSONObject(response);
JSONObject data = jsonObject.getJSONObject("data");
JSONArray bukken_list = data.getJSONArray("bukken_list");
for (int i = 0; i < bukken_list.length(); i++) {
JSONObject returnBukken = bukken_list.getJSONObject(i);
String latitude = returnBukken.getString("ido_hokui"); //latitude
String longitude = returnBukken.getString("keido_tokei"); //longitude
final String bukken_name = returnBukken.getString("bukken_name"); //longitude
final Double x = Double.parseDouble(latitude);
final Double y = Double.parseDouble(longitude);
System.out.println("COORDINATES: " + i);
System.out.println("LATITUDE: " + latitude);
System.out.println("LONGITUDE: " + longitude);
System.out.println("BUKKEN NAME: " + longitude);
LatLng japan = new LatLng(x, y);
MarkerOptions client_marker = new MarkerOptions().position(new LatLng(x, y));
client_marker.icon(BitmapDescriptorFactory.fromResource(R.drawable.mapicon_rent));
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(japan, 10f));
mMap.addMarker(client_marker);
mMap.moveCamera(CameraUpdateFactory.newLatLng(japan));
mMap.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
#Override
public boolean onMarkerClick(Marker arg0) {
//FAULT: does not get value of each marker
System.out.println("MARKER " + x + " " + y + " " + bukken_name);
return true;
}
});
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
int x = 1;
// Anything you want
}
});

Set bukken_name as marker's tag:
Marker marker = mMap.addMarker(client_marker);
marker.setTag(bukken_name);
On marker click:
public boolean onMarkerClick(Marker clickedMarker) {
LatLng location = clickedMarker.getPosition();
System.out.println("MARKER " + location.latitude + " " + location.longitude + " " + clickedMarker.getTag());
return true;
}

How to draw route and calculate distance between multiple markers on google map in android

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.
Direction api Documentation
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 Retrofit 2 for connecting to network. (https://square.github.io/retrofit/)
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**

How to remove the extra polyline from google maps api android

I have added a waypoint and drawn the polyline from start to destination through the waypoint. But an extra straight line is drawn from start to destination. How can I remove it ?
The code below shows the ParserTask and getDirections URL.
private class ParserTask extends AsyncTask<String, Integer, List<List<HashMap<String, String>>>> {
// Parsing the data in non-ui thread
#Override
protected List<List<HashMap<String, String>>> doInBackground(String... jsonData) {
JSONObject jObject;
List<List<HashMap<String, String>>> routes = null;
try {
jObject = new JSONObject(jsonData[0]);
DirectionsJSONParser parser = new DirectionsJSONParser();
routes = parser.parse(jObject);
Log.d("routes", routes.toString());
Log.d("jObject", jObject.toString());
} catch (Exception e) {
e.printStackTrace();
}
return routes;
}
#Override
protected void onPostExecute(List<List<HashMap<String, String>>> result) {
ArrayList<LatLng> points = new ArrayList<LatLng>();;
PolylineOptions lineOptions = new PolylineOptions();;
lineOptions.width(2);
lineOptions.color(Color.RED);
MarkerOptions markerOptions = new MarkerOptions();
// Traversing through all the routes
for(int i=0;i<result.size();i++){
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
for (int j = 0; j < path.size(); j++) {
HashMap<String, String> point = path.get(j);
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
lineOptions.addAll(points);
lineOptions.width(12);
lineOptions.color(Color.RED);
lineOptions.geodesic(true);
}
// Drawing polyline in the Google Map for the i-th route
mMap.addPolyline(lineOptions);
}
}
private String getDirectionsUrl(LatLng origin_start, LatLng dest, LatLng waypoint_xx) {
String origin = "origin=" + origin_start.latitude + "," + origin_start.longitude;
//String waypointss = "waypoints=optimize:true|" + waypoint_xx.latitude + "," + waypoint_xx.longitude ;
String destination = "destination=" + dest.latitude + "," + dest.longitude;
// Waypoints
String waypoints = "";
for(int i=2;i<markerPoints.size();i++){
LatLng point = (LatLng) markerPoints.get(i);
if(i==2)
waypoints = "waypoints=";
waypoints += point.latitude + "," + point.longitude + "|";
}
String sensor = "sensor=false";
String alternative = "alternatives=false";
String params = origin + "&" + destination + "&" + alternative + "&" + sensor + "&" + waypoints ;
String output = "json";
String url = "https://maps.googleapis.com/maps/api/directions/"
+ output + "?" + params;
return url;
}
This code is the Directions JSON Parser
public class DirectionsJSONParser {
/** Receives a JSONObject and returns a list of lists containing latitude and longitude */
public List<List<HashMap<String,String>>> parse(JSONObject jObject){
List<List<HashMap<String, String>>> routes = new ArrayList<List<HashMap<String,String>>>() ;
JSONArray jRoutes = null;
JSONArray jLegs = null;
JSONArray jSteps = null;
try {
jRoutes = jObject.getJSONArray("routes");
/** Traversing all routes */
for(int i=0;i<jRoutes.length();i++){
jLegs = ( (JSONObject)jRoutes.get(i)).getJSONArray("legs");
List path = new ArrayList<HashMap<String, String>>();
/** Traversing all legs */
for(int j=0;j<jLegs.length();j++){
jSteps = ( (JSONObject)jLegs.get(j)).getJSONArray("steps");
/** Traversing all steps */
for(int k=0;k<jSteps.length();k++){
String polyline = "";
polyline = (String)((JSONObject)((JSONObject)jSteps.get(k)).get("polyline")).get("points");
List list = decodePoly(polyline);
/** Traversing all points */
for(int l=0;l <list.size();l++){
HashMap<String, String> hm = new HashMap<String, String>();
hm.put("lat", Double.toString(((LatLng)list.get(l)).latitude) );
hm.put("lng", Double.toString(((LatLng)list.get(l)).longitude) );
path.add(hm);
}
}
routes.add(path);
}
}
} catch (JSONException e) {
e.printStackTrace();
}catch (Exception e){
}
return routes;
}
/**
* Method to decode polyline points
* Courtesy : http://jeffreysambells.com/2010/05/27/decoding-polylines-from-google-maps-direction-api-with-java
* */
private List decodePoly(String encoded) {
List poly = new ArrayList();
int index = 0, len = encoded.length();
int lat = 0, lng = 0;
while (index < len) {
int b, shift = 0, result = 0;
do {
b = encoded.charAt(index++) - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
lat += dlat;
shift = 0;
result = 0;
do {
b = encoded.charAt(index++) - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
lng += dlng;
LatLng p = new LatLng((((double) lat / 1E5)),
(((double) lng / 1E5)));
poly.add(p);
}
return poly;
}
}
This is the Download Task
private class DownloadTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... url) {
String data = "";
try {
data = downloadUrl(url[0]);
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
Log.d("parserTask data", data.toString());
return data;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
ParserTask parserTask = new ParserTask();
Log.d("parserTask result", result.toString());
parserTask.execute(result);
}
}
And finally the onMapReady method
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
UiSettings uiSettings = googleMap.getUiSettings();
//uiSettings.setCompassEnabled(false);
uiSettings.setZoomControlsEnabled(true);
//-------------
// mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
//Initialize Google Play Services
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
//Location Permission already granted
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
} else {
//Request Location Permission
checkLocationPermission();
}
}
else {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
//-------------
DatabaseReference myRef = FirebaseDatabase.getInstance().getReference().child("location");
myRef.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
NotificationCompat.Builder builder =
new NotificationCompat.Builder(MapsActivity.this)
.setSmallIcon(R.drawable.applogo)
.setContentTitle("Trip Request")
.setContentText("Click to accept trip!");
manager = (NotificationManager) MapsActivity.this.getSystemService( MapsActivity.this.NOTIFICATION_SERVICE );
manager.notify(0, builder.build());
// sendNotification();
startLatFB = (Double) dataSnapshot.child("startLat").getValue();
startLonFB = (Double) dataSnapshot.child("startLon").getValue();
endLatFB = (Double) dataSnapshot.child("endLat").getValue();
endLonFB = (Double) dataSnapshot.child("endLon").getValue();
Log.d("startLat", startLatFB.toString());
Log.d("startLon", startLonFB.toString());
Log.d("endLat", endLatFB.toString());
Log.d("endLon", endLonFB.toString());
if (markerPoints.size() > 1) {
markerPoints.clear();
mMap.clear();
}
double startLat = startLatFB; //SLIIT
double startLon = startLonFB;
double wayPointLat = 6.9040322; //FAB - Malabe
double wayPointLon = 79.948803;
double wayPointLatTwo = 6.053519; //FAB - Malabe
double wayPointLonTwo = 80.220977;
double endLat = endLatFB; //MAS
double endLon = endLonFB;
LatLng start_latLng = new LatLng(startLat, startLon);
LatLng waypoint_latLng = new LatLng(wayPointLat, wayPointLon);
LatLng end_latLng = new LatLng(endLat, endLon);
// LatLng start_latLng = new LatLng(startLatFB, startLonFB);
// LatLng waypoint_latLng = new LatLng(wayPointLat, wayPointLon);
// LatLng end_latLng = new LatLng(endLatFB, endLonFB);
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(start_latLng, 11));
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(start_latLng,11f));
// start_latLng = startLatFB;
// Adding new item to the ArrayList
markerPoints.add(start_latLng);
markerPoints.add(end_latLng);
markerPoints.add(waypoint_latLng);
// Creating MarkerOptions
MarkerOptions options = new MarkerOptions();
MarkerOptions optionsTwo = new MarkerOptions();
MarkerOptions optionsThree = new MarkerOptions();
BitmapDescriptor icon = BitmapDescriptorFactory.fromResource(R.drawable.startlocation);
BitmapDescriptor icon2 = BitmapDescriptorFactory.fromResource(R.drawable.endlocation);
// Setting the position of the marker
options.position(start_latLng);
optionsTwo.position(end_latLng);
optionsThree.position(waypoint_latLng);
if (markerPoints.size() == 1) {
options.icon(icon);
} else if (markerPoints.size() == 2) {
options.icon(icon2);
}
// Add new marker to the Google Map Android API V2
mMap.addMarker(options);
mMap.addMarker(optionsTwo);
mMap.addMarker(optionsThree);
// Checks, whether start and end locations are captured
if (markerPoints.size() >= 3) {
LatLng origin = (LatLng) markerPoints.get(0);
LatLng dest = (LatLng) markerPoints.get(1);
LatLng waypointss = (LatLng) markerPoints.get(2);
Log.d("origin url", origin.toString());
Log.d("dest url", origin.toString());
Log.d("waypoint url", origin.toString());
// Getting URL to the Google Directions API
String url = getDirectionsUrl(origin, dest, waypointss);
DownloadTask downloadTask = new DownloadTask();
// Start downloading json data from Google Directions API
downloadTask.execute(url);
Log.d("DownloadTask url", url);
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}

Try initializing new Arraylist of Points each time while traversing.
Here is a sample:
#Override
protected void onPostExecute(List<List<HashMap<String, String>>> result) {
ArrayList<LatLng> points = null;
PolylineOptions lineOptions = null;
// Traversing through all the routes
for(int i=0;i<result.size();i++){
points = new ArrayList<LatLng>(); //initialize here
lineOptions = new PolylineOptions();
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
for (int j = 0; j < path.size(); j++) {
HashMap<String, String> point = path.get(j);
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
lineOptions.addAll(points);
lineOptions.width(12);
lineOptions.color(Color.RED);
}
// Drawing polyline in the Google Map for the i-th route
mMap.addPolyline(lineOptions);
}
}
For detail implementation Go through This Link

Draw Routes between multiple points on map

I am new to android. I want to draw routes between multiple markers. I a, getting latitude, longitude and datetime from server. Now i want to show route between the points. I have stored them in arraylist. Here is how i am getting the points in async task doInBackground().
newLatt= new ArrayList<String>();
newLongg= new ArrayList<String>();
newdatTime= new ArrayList<String>();
JSONArray arr = new JSONArray(strServerResponse);
for (int i = 0; i < arr.length(); i++) {
JSONObject jsonObj1 = arr.getJSONObject(i);
String status = jsonObj1.optString("status");
if (status!="false"){
Pojo pojo = new Pojo();
String latitude = jsonObj1.optString("Latitude");
String longitude = jsonObj1.optString("Longitude");
String date_time = jsonObj1.optString("date_time");
newLatt.add(latitude);
newLongg.add(longitude);
newdatTime.add(date_time);
}else {
Handler handler = new Handler(Looper.getMainLooper());
handler.post(new Runnable() {
#Override
public void run() {
AlertDialog alertDialog = new AlertDialog.Builder(
MapActivity.this).create();
alertDialog.setMessage("Locations Not Available");
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
}
});
alertDialog.show();
}
}
);
}
and in postExecute() method i am showing markers
SupportMapFragment supportMapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
map = supportMapFragment.getMap();
map.setMyLocationEnabled(true);
if (newLatt.size()>0){
for (int i = 0; i < newLatt.size(); i++) {
Double lati = Double.parseDouble(newLatt.get(i));
Double longi = Double.parseDouble(newLongg.get(i));
String dattme = newdatTime.get(i);
dest = new LatLng(lati, longi);
if (map != null) {
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(dest);
map.moveCamera(CameraUpdateFactory.newLatLng(dest));
map.animateCamera(CameraUpdateFactory.zoomTo(15));
markerOptions.icon(BitmapDescriptorFactory
.defaultMarker(BitmapDescriptorFactory.HUE_RED));
markerOptions.title("" + dattme);
map.addMarker(markerOptions);
map.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
#Override
public boolean onMarkerClick(Marker marker) {
marker.showInfoWindow();
return false;
}
});
UPDATE
PolylineOptions rectOptions = new PolylineOptions();
//this is the color of route
rectOptions.color(Color.argb(255, 85, 166, 27));
LatLng startLatLng = null;
LatLng endLatLng = null;
SupportMapFragment supportMapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
map = supportMapFragment.getMap();
map.setMyLocationEnabled(true);
if (newLatt.size()>0){
for (int i = 0; i < newLatt.size(); i++) {
Double lati = Double.parseDouble(newLatt.get(i));
Double longi = Double.parseDouble(newLongg.get(i));
String dattme = newdatTime.get(i);
dest = new LatLng(lati, longi);
if (map != null) {
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(dest);
map.moveCamera(CameraUpdateFactory.newLatLng(dest));
map.animateCamera(CameraUpdateFactory.zoomTo(15));
markerOptions.icon(BitmapDescriptorFactory
.defaultMarker(BitmapDescriptorFactory.HUE_RED));
markerOptions.title("" + dattme);
map.addMarker(markerOptions);
map.setOnMarkerClickListener(new GoogleMap.OnMarkerClickListener() {
#Override
public boolean onMarkerClick(Marker marker) {
marker.showInfoWindow();
return false;
}
});
LatLng latlng = new LatLng(lati,
longi);
if (i == 0) {
startLatLng = latlng;
}
if (i == newLatt.size() - 1) {
endLatLng = latlng;
}
rectOptions.add(latlng);
String url = getDirectionsUrl(startLatLng, endLatLng);
DownloadTask downloadTask = new DownloadTask();
downloadTask.execute(url);
}
}
map.addPolyline(rectOptions);
getDirections:
private String getDirectionsUrl(LatLng origin, LatLng dest) {
// Origin of route
String str_origin = "origin=" + origin.latitude + ","
+ origin.longitude;
// Destination of route
String str_dest = "destination=" + dest.latitude + "," + dest.longitude;
// Sensor enabled
String sensor = "sensor=false";
// Building the parameters to the web service
String parameters = str_origin + "&" + str_dest + "&" + sensor;
// Output format
String output = "json";
// Building the url to the web service
String url = "https://maps.googleapis.com/maps/api/directions/"
+ output + "?" + parameters;
return url;
}

In your postExecute add the following code to add ploylines on the map.
PolylineOptions rectOptions = new PolylineOptions();
//this is the color of route
rectOptions.color(Color.argb(255, 85, 166, 27));
LatLng startLatLng = null;
LatLng endLatLng = null;
for (int i = 0; i < newLatt.size(); i++) {
Double lati = Double.parseDouble(newLatt.get(i));
Double longi = Double.parseDouble(newLongg.get(i));
LatLng latlng = new LatLng(lati,
longi);
if (i == 0) {
startLatLng = latlng;
}
if (i == jArr.length() - 1) {
endLatLng = latlng;
}
rectOptions.add(latlng);
}
map.addPolyline(rectOptions);
Happy coding...

Android does not provide embedded direction service in google map api. To draw route between points you must use google direction services REST API .
You can get complete code and description from http://wptrafficanalyzer.in/blog/drawing-driving-route-directions-between-two-locations-using-google-directions-in-google-map-android-api-v2/
ArrayList<LatLng> points = null;
PolylineOptions lineOptions = null;
MarkerOptions markerOptions = new MarkerOptions();
// Traversing through all the routes
for(int i=0;i<result.size();i++){
points = new ArrayList<LatLng>();
lineOptions = new PolylineOptions();
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
// Fetching all the points in i-th route
for(int j=0;j<path.size();j++){
HashMap<String,String> point = path.get(j);
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
// Adding all the points in the route to LineOptions
lineOptions.addAll(points);
lineOptions.width(2);
lineOptions.color(Color.RED);
}
// Drawing polyline in the Google Map for the i-th route
map.addPolyline(lineOptions);

Delete or remove the polylines in google map api v2

I am trying this from quite long so is why i am here seeking for some serious help!!
In my application i am suppose to plot more than 2 alternative routes onclick of a button, say in my application i have 3 buttons such as r1,r2 and r3.When i enter the source and destination locations in my application's respective's edittexts and click enter then i shall be plotting by default r1 so now when i click on r2 button the path/route plotted on the map previously should be erased/deleted and the new alternative path/route should be plotted on the map but isnt happening that way instead of erasing the previous path/route it is plotting both the routes on the map:( can someone please help me?
Here is my code.
List<RoutesDictionary> routeDicList = new ArrayList<RoutesDictionary>();
routeTwo.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
map.clear();
routeDicList.clear();
routeType = 2;
rout = "walking";
new TrafficData().execute();
Log.d("TH routeTwo", "In routeTwo After" +
`enter code here`routeDicList.size());
}
});
public class TrafficData extends AsyncTask<Context, String, String> {
routeTwo.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
map.clear();
routeDicList.clear();
routeType = 2;
rout = "walking";
new TrafficData().execute();
}
});
#Override
protected String doInBackground(Context... params) {
try {
if (!via_route.equals("")) {
url = "http://maps.googleapis.com/maps/api/directions/json?origin="
+ sourceAdd
+ "&destination="
+ destinationAdd
+ "&waypoints=via:"
+ via_route
+ "&sensor=false&mode=" + rout;
} else {
url = "http://maps.googleapis.com/maps/api/directions/json?origin="
+ sourceAdd
+ "&destination="
+ destinationAdd
+ "&sensor=false&mode=" + rout;
}
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpGet httpPost = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpPost);
result = EntityUtils.toString(httpResponse.getEntity());
Log.v("Traffic App : ", "The Traffic App result is : "
+ result);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
} catch (Exception e) {
e.printStackTrace();
}
return result;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
Log.v("Traffic App : ", "The Traffic App resultTraffic is : "
+ resultTraffic);
try {
JSONObject routesObj = new JSONObject(result);
String status = routesObj.getString("status");
if (status.equals("OK")) {
routesDictionary = new RoutesDictionary();
allRouteDic.addSrcAddress(sourceAdd);
allRouteDic.addDesAddress(destinationAdd);
AllRoutes.allRoutes.add(allRouteDic);
Log.v("***********************", "THE ***** Array list : ");
JSONArray routesArr = routesObj.getJSONArray("routes");
JSONObject mainObj = routesArr.getJSONObject(0);
JSONArray legsArr = mainObj.getJSONArray("legs");
int legsSize = legsArr.length();
for (int i = 0; i < legsSize; i++) {
routesDictionary.addlegsDistance(legsArr.getJSONObject(
i).getJSONObject("distance"));
routesDictionary.addlegsDuration(legsArr.getJSONObject(
i).getJSONObject("duration"));
routesDictionary.addlegsEndaddress(legsArr
.getJSONObject(i).getString("end_address"));
routesDictionary
.addlegsEndlocation(legsArr.getJSONObject(i)
.getJSONObject("end_location"));
routesDictionary.addlegsStartaddress(legsArr
.getJSONObject(i).getString("start_address"));
routesDictionary.addlegsStartlocation(legsArr
.getJSONObject(i).getJSONObject(
"start_location"));
routeDicList.add(routesDictionary);
JSONArray stepsArr = legsArr.getJSONObject(i)
.getJSONArray("steps");
int stepsLen = stepsArr.length();
for (int j = 0; j < stepsLen; j++) {
routesDictionary
.addlegs_StepsDistance(stepsArr
.getJSONObject(j).getJSONObject(
"distance"));
routesDictionary
.addlegs_StepsDuration(stepsArr
.getJSONObject(j).getJSONObject(
"duration"));
routesDictionary.addlegs_StepsEndlocation(stepsArr
.getJSONObject(j).getJSONObject(
"end_location"));
routesDictionary.addlegs_StepsHtmlInstruct(stepsArr
.getJSONObject(j).getString(
"html_instructions"));
routesDictionary
.addlegs_StepsPloyline(stepsArr
.getJSONObject(j).getJSONObject(
"polyline"));
routesDictionary
.addlegs_StepsStartlocation(stepsArr
.getJSONObject(j).getJSONObject(
"start_location"));
routesDictionary.addlegs_StepsTravelmode(stepsArr
.getJSONObject(j).getString("travel_mode"));
routeDicList.add(routesDictionary);
}
}
int strLoc = routeDicList.get(0)
.getlegs_StepsStartlocation().size();
for (int k = 0; k < strLoc; k++) {
routesDictionary.addStrLatit(routeDicList.get(0)
.getlegs_StepsStartlocation().get(k)
.getString("lat"));
routesDictionary.addStrlongi(routeDicList.get(0)
.getlegs_StepsStartlocation().get(k)
.getString("lng"));
routeDicList.add(routesDictionary);
}
int endLoc = routeDicList.get(0).getlegs_StepsEndlocation()
.size();
for (int l = 0; l < endLoc; l++) {
routesDictionary.addEndLatit(routeDicList.get(0)
.getlegs_StepsEndlocation().get(l)
.getString("lat"));
routesDictionary.addEndLongi(routeDicList.get(0)
.getlegs_StepsEndlocation().get(l)
.getString("lng"));
routeDicList.add(routesDictionary);
}
int strL = routeDicList.get(0).getStrLatit().size();
for (int m = 0; m < strL; m++) {
Log.v("Traffic : ", "*** Latitude and Longi *** : "
+ routeDicList.get(0).getStrLatit().get(m)
+ " "
+ routeDicList.get(0).getStrLong().get(m));
}
int endL = routeDicList.get(0).getEndLatit().size();
for (int m = 0; m < endL; m++) {
Log.v("Traffic : ", "### Latitude and Longi ### : "
+ routeDicList.get(0).getEndLatit().get(m)
+ " "
+ routeDicList.get(0).getEndLong().get(m));
}
rectOptions = new PolylineOptions();
Log.v("*****************", "The RECTPOINTS SIZE : "
+ rectOptions.getPoints().size());
rectOptions.getPoints().clear();
switch (routeType) {
case 1:
rectOptions.color(Color.RED);
break;
case 2:
rectOptions.color(Color.BLUE);
break;
case 3:
rectOptions.color(Color.GREEN);
break;
default:
break;
}
rectOptions.width(4);
for (int i = 1; i < strL; i++) {
rectOptions.add(new LatLng(Double.valueOf(routeDicList
.get(0).getStrLatit().get(i)), Double
.valueOf(routeDicList.get(0).getStrLong()
.get(i))));
}
// Get back the mutable Polygon
map.clear();
polyline = map.addPolyline(rectOptions.geodesic(false));
polyline.remove();
polyline = map.addPolyline(rectOptions.geodesic(true));
double lng = Double.valueOf(routeDicList.get(0)
.getlegs_StepsStartlocation().get(0)
.getString("lng"));
double lat = Double.valueOf(routeDicList.get(0)
.getlegs_StepsStartlocation().get(0)
.getString("lat"));
map.animateCamera(CameraUpdateFactory.newLatLngZoom(
new LatLng(lat, lng), 14.0f));
// start longitude and latitude
double startlng = Double
.valueOf(routeDicList.get(0)
.getlegs_StepsEndlocation().get(0)
.getString("lng"));
double startlat = Double
.valueOf(routeDicList.get(0)
.getlegs_StepsEndlocation().get(0)
.getString("lat"));
// start location marker
addMarker(startlat, startlng);
// end longitude and latitude
double endlng = Double.valueOf(routeDicList.get(0)
.getlegs_StepsStartlocation().get(endLoc - 1)
.getString("lng"));
double endlat = Double.valueOf(routeDicList.get(0)
.getlegs_StepsStartlocation().get(endLoc - 1)
.getString("lat"));
// end location marker
addMarker(endlat, endlng);
}
} catch (JSONException e) {
e.printStackTrace();
}
}

1- You set the OnClickListener for routeTwo button twice one in the main class and one in the AsyncTask , the one in the AsyncTask should be removed.
2- Pressing the button twice fast would produce your problem, because you will start two separably AsyncTasks each one will draw a route so both routes would be displayed, i prefer using just one AsyncTask as a global variable and before running new one check if there is a running AsyncTask ,this could be done by
if(trafficData != null && trafficData.getStatus() != AsyncTask.Status.FINISHED){
trafficData .cancel(true);
}