Develop Reference

Roads googleapi: Some places missing and lines passing through edifices

I'm using the Roads Google API passing a list of positions and I want to paint lines in the most probable road driven by a car by these points.
Something is going wrong because some points are not being crossed by the lines and the lines are not using only roads, some of them pass through edifices or the sea with straight lines. I added markers to show the problem.
Is something wrong in the code?
Some sample code to get this error:
public class MainActivity extends AppCompatActivity implements OnMapReadyCallback {
private GoogleMap mGoogleMap;
private MapFragment mapFragment;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mapFragment = (MapFragment) getFragmentManager()
.findFragmentById(R.id.map_fragment);
mapFragment.getMapAsync(this);
}
#Override
public void onMapReady(GoogleMap googleMap) {
mGoogleMap = googleMap;
List<LatLng> sourcePoints = new ArrayList<>();
sourcePoints.add(new LatLng(39.4321055669415, -0.343169529033198));
sourcePoints.add(new LatLng(39.4279737815806, -0.334743742804801));
sourcePoints.add(new LatLng(39.4235262880062, -0.341102620562518));
sourcePoints.add(new LatLng(39.4216973481355, -0.340624944612178));
sourcePoints.add(new LatLng(39.4194951574233, -0.335974058847626));
sourcePoints.add(new LatLng(39.4216760915054, -0.340342003540913));
sourcePoints.add(new LatLng(39.4235646246302, -0.340901154018858));
sourcePoints.add(new LatLng(39.4321131753486, -0.342995147300383));
PolylineOptions polyLineOptions = new PolylineOptions();
polyLineOptions.addAll(sourcePoints);
polyLineOptions.width(5);
polyLineOptions.color(Color.BLUE);
mGoogleMap.addPolyline(polyLineOptions);
mGoogleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(sourcePoints.get(0), 15));
List<LatLng> snappedPoints = new ArrayList<>();
new GetSnappedPointsAsyncTask().execute(sourcePoints, null, snappedPoints);
}
private String buildRequestUrl(List<LatLng> trackPoints) {
StringBuilder url = new StringBuilder();
url.append("https://roads.googleapis.com/v1/snapToRoads?path=");
for (LatLng trackPoint : trackPoints) {
url.append(String.format("%8.5f", trackPoint.latitude));
url.append(",");
url.append(String.format("%8.5f", trackPoint.longitude));
url.append("|");
}
url.delete(url.length() - 1, url.length());
url.append("&interpolate=true");
url.append(String.format("&key=%s", <your_Google_Maps_API_key>);
return url.toString();
}
private class GetSnappedPointsAsyncTask extends AsyncTask<List<LatLng>, Void, List<LatLng>> {
protected void onPreExecute() {
super.onPreExecute();
}
protected List<LatLng> doInBackground(List<LatLng>... params) {
List<LatLng> snappedPoints = new ArrayList<>();
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(buildRequestUrl(params[0]));
connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuilder jsonStringBuilder = new StringBuilder();
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line+"\n");
jsonStringBuilder.append(line);
jsonStringBuilder.append("\n");
}
JSONObject jsonObject = new JSONObject(jsonStringBuilder.toString());
JSONArray snappedPointsArr = jsonObject.getJSONArray("snappedPoints");
for (int i = 0; i < snappedPointsArr.length(); i++) {
JSONObject snappedPointLocation = ((JSONObject) (snappedPointsArr.get(i))).getJSONObject("location");
double lattitude = snappedPointLocation.getDouble("latitude");
double longitude = snappedPointLocation.getDouble("longitude");
snappedPoints.add(new LatLng(lattitude, longitude));
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return snappedPoints;
}
#Override
protected void onPostExecute(List<LatLng> result) {
super.onPostExecute(result);
PolylineOptions polyLineOptions = new PolylineOptions();
polyLineOptions.addAll(result);
polyLineOptions.width(5);
polyLineOptions.color(Color.RED);
mGoogleMap.addPolyline(polyLineOptions);
LatLngBounds.Builder builder = new LatLngBounds.Builder();
builder.include(result.get(0));
builder.include(result.get(result.size()-1));
LatLngBounds bounds = builder.build();
mGoogleMap.animateCamera(CameraUpdateFactory.newLatLngBounds(bounds, 10));
}
}
}

It's everything ok with your code: there are not enough points for Snap to Roads. You should use Google Maps Directions API instead of Snap to Roads API to get lacking points: format route request, receive and parse response - you need overview_polyline tag points String value - it's encoded polyline of route part For your source points (blue path on figure):
List<LatLng> sourcePoints = new ArrayList<>();
sourcePoints.add(new LatLng(39.4321055669415, -0.343169529033198));
sourcePoints.add(new LatLng(39.4279737815806, -0.334743742804801));
sourcePoints.add(new LatLng(39.4235262880062, -0.341102620562518));
sourcePoints.add(new LatLng(39.4216973481355, -0.340624944612178));
sourcePoints.add(new LatLng(39.4194951574233, -0.335974058847626));
sourcePoints.add(new LatLng(39.4216760915054, -0.340342003540913));
sourcePoints.add(new LatLng(39.4235646246302, -0.340901154018858));
sourcePoints.add(new LatLng(39.4321131753486, -0.342995147300383));
with Google Maps Directions API implementation like that:
public class MainActivity extends AppCompatActivity implements OnMapReadyCallback {
private static final String TAG = MainActivity.class.getSimpleName();
private GoogleMap mGoogleMap;
private MapFragment mapFragment;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mapFragment = (MapFragment) getFragmentManager()
.findFragmentById(R.id.map_fragment);
mapFragment.getMapAsync(this);
}
#Override
public void onMapReady(GoogleMap googleMap) {
mGoogleMap = googleMap;
List<LatLng> sourcePoints = new ArrayList<>();
sourcePoints.add(new LatLng(39.4321055669415, -0.343169529033198));
sourcePoints.add(new LatLng(39.4279737815806, -0.334743742804801));
sourcePoints.add(new LatLng(39.4235262880062, -0.341102620562518));
sourcePoints.add(new LatLng(39.4216973481355, -0.340624944612178));
sourcePoints.add(new LatLng(39.4194951574233, -0.335974058847626));
sourcePoints.add(new LatLng(39.4216760915054, -0.340342003540913));
sourcePoints.add(new LatLng(39.4235646246302, -0.340901154018858));
sourcePoints.add(new LatLng(39.4321131753486, -0.342995147300383));
PolylineOptions polyLineOptions = new PolylineOptions();
polyLineOptions.addAll(sourcePoints);
polyLineOptions.width(5);
polyLineOptions.color(Color.BLUE);
mGoogleMap.addPolyline(polyLineOptions);
mGoogleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(sourcePoints.get(0), 15));
List<LatLng> directionsPoints = new ArrayList<>();
new GetDirectionPointsAsyncTask().execute(sourcePoints, null, directionsPoints);
}
private String buildDirectionsUrl(List<LatLng> trackPoints) {
if (trackPoints.size() < 2) {
return null;
}
final LatLng origin = trackPoints.get(0);
final LatLng dest = trackPoints.get(trackPoints.size() - 1);
StringBuilder url = new StringBuilder();
url.append("https://maps.googleapis.com/maps/api/directions/json?");
url.append(String.format("origin=%8.5f,%8.5f", origin.latitude, origin.longitude));
url.append(String.format("&destination=%8.5f,%8.5f", dest.latitude, dest.longitude));
// add waypoints, if they exists
if (trackPoints.size() > 2) {
url.append("&waypoints=");
LatLng wayPoint;
for (int ixWaypoint = 1; ixWaypoint < trackPoints.size() - 2; ixWaypoint++) {
wayPoint = trackPoints.get(ixWaypoint);
url.append(String.format("%8.5f,%8.5f|", wayPoint.latitude, wayPoint.longitude));
}
url.delete(url.length() - 1, url.length());
}
url.append(String.format("&key=%s", getResources().getString(R.string.google_maps_key)));
return url.toString();
}
private class GetDirectionPointsAsyncTask extends AsyncTask<List<LatLng>, Void, List<LatLng>> {
protected void onPreExecute() {
super.onPreExecute();
}
protected List<LatLng> doInBackground(List<LatLng>... params) {
List<LatLng> routePoints = new ArrayList<>();
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(buildDirectionsUrl(params[0]));
connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.connect();
int responseCode = connection.getResponseCode();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuilder jsonStringBuilder = new StringBuilder();
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line+"\n");
jsonStringBuilder.append(line);
jsonStringBuilder.append("\n");
}
JSONObject jsonRoot = new JSONObject(jsonStringBuilder.toString());
JSONArray jsonRoutes = jsonRoot.getJSONArray("routes");
if (jsonRoutes.length() < 1) {
return null;
}
JSONObject jsonRoute = jsonRoutes.getJSONObject(0);
JSONObject overviewPolyline = jsonRoute.getJSONObject("overview_polyline");
String overviewPolylineEncodedPoints = overviewPolyline.getString("points");
routePoints = decodePoly(overviewPolylineEncodedPoints);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return routePoints;
}
#Override
protected void onPostExecute(List<LatLng> result) {
super.onPostExecute(result);
PolylineOptions polyLineOptions = new PolylineOptions();
polyLineOptions.addAll(result);
polyLineOptions.width(5);
polyLineOptions.color(Color.RED);
mGoogleMap.addPolyline(polyLineOptions);
LatLngBounds.Builder builder = new LatLngBounds.Builder();
builder.include(result.get(0));
builder.include(result.get(result.size()-1));
LatLngBounds bounds = builder.build();
mGoogleMap.animateCamera(CameraUpdateFactory.newLatLngBounds(bounds, 10));
}
}
//
// Method to decode polyline points
// Courtesy : http://jeffreysambells.com/2010/05/27/decoding-polylines-from-google-maps-direction-api-with-java
private List<LatLng> decodePoly(String encoded) {
List<LatLng> 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;
}
}
you get something like that (red path on figure):
NB! Don't forget to allow Directions API on Google APIs Console
More details about Direction API here and in many online tutorials/examples.

How do I track the location of a user throughout the day in Google Maps?

How would you track the location of a user for the entire day, like the timeline in Google maps?
I have two ideas
For example, if I have 200 LatLng values per day, how do I pass all of these LatLng values to Google map as points? I got one google doc reference in that I can track up to 10 locations points only.
Is there any Google API to track the user throughout the whole day and make a timeline for it?

If you have 200 LatLng point you always can just draw them as polyline:
...
final List<LatLng> polylinePoints = new ArrayList<>();
polylinePoints.add(new LatLng(<Point1_Lat>, <Point1_Lng>));
polylinePoints.add(new LatLng(<Point2_Lat>, <Point2_Lng>));
...
final Polyline polyline = mGoogleMap.addPolyline(new PolylineOptions()
.addAll(polylinePoints)
.color(Color.BLUE)
.width(20));
and, if you need, snap them to roads with Snap to Road part of Google Maps Roads API:
...
List<LatLng> snappedPoints = new ArrayList<>();
new GetSnappedPointsAsyncTask().execute(polylinePoints, null, snappedPoints);
...
private class GetSnappedPointsAsyncTask extends AsyncTask<List<LatLng>, Void, List<LatLng>> {
protected void onPreExecute() {
super.onPreExecute();
}
protected List<LatLng> doInBackground(List<LatLng>... params) {
List<LatLng> snappedPoints = new ArrayList<>();
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(buildRequestUrl(params[0]));
connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuilder jsonStringBuilder = new StringBuilder();
StringBuffer buffer = new StringBuffer();
String line = "";
while ((line = reader.readLine()) != null) {
buffer.append(line+"\n");
jsonStringBuilder.append(line);
jsonStringBuilder.append("\n");
}
JSONObject jsonObject = new JSONObject(jsonStringBuilder.toString());
JSONArray snappedPointsArr = jsonObject.getJSONArray("snappedPoints");
for (int i = 0; i < snappedPointsArr.length(); i++) {
JSONObject snappedPointLocation = ((JSONObject) (snappedPointsArr.get(i))).getJSONObject("location");
double lattitude = snappedPointLocation.getDouble("latitude");
double longitude = snappedPointLocation.getDouble("longitude");
snappedPoints.add(new LatLng(lattitude, longitude));
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
try {
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return snappedPoints;
}
#Override
protected void onPostExecute(List<LatLng> result) {
super.onPostExecute(result);
PolylineOptions polyLineOptions = new PolylineOptions();
polyLineOptions.addAll(result);
polyLineOptions.width(5);
polyLineOptions.color(Color.RED);
mGoogleMap.addPolyline(polyLineOptions);
LatLngBounds.Builder builder = new LatLngBounds.Builder();
builder.include(result.get(0));
builder.include(result.get(result.size()-1));
LatLngBounds bounds = builder.build();
mGoogleMap.animateCamera(CameraUpdateFactory.newLatLngBounds(bounds, 10));
}
}
private String buildRequestUrl(List<LatLng> trackPoints) {
StringBuilder url = new StringBuilder();
url.append("https://roads.googleapis.com/v1/snapToRoads?path=");
for (LatLng trackPoint : trackPoints) {
url.append(String.format("%8.5f", trackPoint.latitude));
url.append(",");
url.append(String.format("%8.5f", trackPoint.longitude));
url.append("|");
}
url.delete(url.length() - 1, url.length());
url.append("&interpolate=true");
url.append(String.format("&key=%s", <your_Google_Maps_API_key>);
return url.toString();
}
If distance between adjacent points too big, you can use Waypoints part of Directions API to get directions between that points and draw polyline with results of waypoints request.

Finally I got solution for this, You can able to get latlng every 15 mins what every you want.
I got reference from google sample github we can run background service using PendingIntent or we can use Broadcast Receiver.
public class LocationUpdatesIntentService extends IntentService {
private static final String ACTION_PROCESS_UPDATES =
"com.google.android.gms.location.sample.locationupdatespendingintent.action" +
".PROCESS_UPDATES";
private static final String TAG = LocationUpdatesIntentService.class.getSimpleName();
public LocationUpdatesIntentService() {
// Name the worker thread.
super(TAG);
}
#Override
protected void onHandleIntent(Intent intent) {
if (intent != null) {
final String action = intent.getAction();
if (ACTION_PROCESS_UPDATES.equals(action)) {
LocationResult result = LocationResult.extractResult(intent);
if (result != null) {
List<Location> locations = result.getLocations();
Utils.setLocationUpdatesResult(this, locations);
Utils.sendNotification(this, Utils.getLocationResultTitle(this, locations));
Log.i(TAG, Utils.getLocationUpdatesResult(this));
}
}
}
}
}
Chere here complete reference:
https://github.com/googlesamples/android-play-location
Some of the mobile Background Service is not running..if service is not running follow below steps:
In Xiaomi devices, you just have to add your app to Autostart list, to
do so, follow these simple steps given below:
1.Open Security app on your phone.
2.Tap on Permissions, it'll show you two options: Autostart and
Permissions
3.Tap on Autostart, it'll show you list of apps with on or off toggle
buttons.
4.Turn on toggle of your app, you're done!

Update marker location on the map without opening and closing Activity

I'm having a question about how to do a project that I thought would be simple.
Next I have an app that sends the location of the mobile phone by 10 seconds to MySql, so alright.
But I just need to now display in another app the current location these users on the mapped 10 seconds without having to open and close the Activity.
In this code below the mapping of the markers that come from the Mysql bank using json is displayed. Any tips?
public class MainActivity extends FragmentActivity {
// Google Map
private GoogleMap googleMap;
// Latitude & Longitude
private Double Latitude = 0.00;
private Double Longitude = 0.00;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//*** Permission StrictMode
if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
}
ArrayList<HashMap<String, String>> location = null;
String url = "http://192.168.1.202/android/getLatLon.php";
try {
JSONArray data = new JSONArray(getHttpGet(url));
location = new ArrayList<HashMap<String, String>>();
HashMap<String, String> map;
for(int i = 0; i < data.length(); i++){
JSONObject c = data.getJSONObject(i);
map = new HashMap<String, String>();
map.put("LocationID", c.getString("LocationID"));
map.put("Latitude", c.getString("Latitude"));
map.put("Longitude", c.getString("Longitude"));
map.put("LocationName", c.getString("LocationName"));
location.add(map);
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// *** Display Google Map
googleMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.googleMap)).getMap();
// *** Focus & Zoom
Latitude = Double.parseDouble(location.get(0).get("Latitude").toString());
Longitude = Double.parseDouble(location.get(0).get("Longitude").toString());
LatLng coordinate = new LatLng(Latitude, Longitude);
googleMap.setMapType(com.google.android.gms.maps.GoogleMap.MAP_TYPE_HYBRID);
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(coordinate, 17));
// *** Marker (Loop)
for (int i = 0; i < location.size(); i++) {
Latitude = Double.parseDouble(location.get(i).get("Latitude").toString());
Longitude = Double.parseDouble(location.get(i).get("Longitude").toString());
String name = location.get(i).get("LocationName").toString();
MarkerOptions marker = new MarkerOptions().position(new LatLng(Latitude, Longitude)).title(name);
googleMap.addMarker(marker);
}
}
public static String getHttpGet(String url) {
StringBuilder str = new StringBuilder();
HttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
try {
HttpResponse response = client.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) { // Download OK
HttpEntity entity = response.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(content));
String line;
while ((line = reader.readLine()) != null) {
str.append(line);
}
} else {
Log.e("Log", "Failed to download result..");
}
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return str.toString();
}
}

You can use COUNTDOWN TIMER, COUNT DOWN TIMER EXAMPLE so that every 10 sec it makes network request and you will get response with the updated value.
and you can update your marker with the new LATITUDE, LONGITUDE value. And keep in mind add marker only on the first network request after
that don't need to add marker only you need to change your marker position. .how to change marker position
But i will recommend you its not a good idea to make network request every time(Every 10 sec). it may be possible that user is not changing there location since one hour.so its worthless API call. so it would be better if you use REAL TIME DATABASE(like Firebase real time db). and listen your data change whenever your db value will be updated it will notify you. Firebase Real time DB Doc reference

If you want to update your map on some interval of time without having to open and close thee activity. You should move your logic from onCreate() method.
Thread myLoopingThread = new Thread(new Runnable() {
#Override
public void run() {
while(!Thread.currentThread().isInterrupted()){
final String result = getHttpGet("http://192.168.1.202/android/getLatLon.php");
runOnUiThread(new Runnable() {
#Override
public void run() {
UpdateMap(result);
}
});
Thread.sleep(timeToSleep);
}
}
});
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//do other stuff..
myLoopingThread.start();
}
//also we should stop the thread when its not needed anymore
#Override
protected void onDestroy(){
myLoopingThread.interrupt();
super.onDestroy();
}
void UpdateMap(String input){
ArrayList<HashMap<String, String>> location = null;
try {
JSONArray data = new JSONArray(input);
location = new ArrayList<HashMap<String, String>>();
HashMap<String, String> map;
for(int i = 0; i < data.length(); i++){
JSONObject c = data.getJSONObject(i);
map = new HashMap<String, String>();
map.put("LocationID", c.getString("LocationID"));
map.put("Latitude", c.getString("Latitude"));
map.put("Longitude", c.getString("Longitude"));
map.put("LocationName", c.getString("LocationName"));
location.add(map);
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
// *** Display Google Map
googleMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.googleMap)).getMap();
// *** Focus & Zoom
Latitude = Double.parseDouble(location.get(0).get("Latitude").toString());
Longitude = Double.parseDouble(location.get(0).get("Longitude").toString());
LatLng coordinate = new LatLng(Latitude, Longitude);
googleMap.setMapType(com.google.android.gms.maps.GoogleMap.MAP_TYPE_HYBRID);
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(coordinate, 17));
// *** Marker (Loop)
for (int i = 0; i < location.size(); i++) {
Latitude = Double.parseDouble(location.get(i).get("Latitude").toString());
Longitude = Double.parseDouble(location.get(i).get("Longitude").toString());
String name = location.get(i).get("LocationName").toString();
MarkerOptions marker = new MarkerOptions().position(new LatLng(Latitude, Longitude)).title(name);
googleMap.addMarker(marker);
}
}

How to prevent Polyline from overlapping in google maps android?

Hello guys this may be dumb question but am struggling with this so far haven't found any solution. Now let me ask my doubt am using multiple polyline for plotting multiple routes each and every polyline has different colors but when two point intersects last polyline get overridden how to prevent it. How it must look is only first route should get one color and all the other routes must have same color how to do this let me post the code what i have tried so far:
public class GetDistance extends AsyncTask<Double, Void, String> {
private ProgressDialog pd;
private static final int READ_TIMEOUT = 6000;
private static final int CONNECTION_TIMEOUT = 6000;
private int flag;
public GetDistance(int flag) {
this.flag=flag;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
pd = new ProgressDialog(VisitTravel.this);
pd.setMessage("Please wait");
pd.show();
}
#Override
protected String doInBackground(Double... strings) {
URL url;
try {
url = new URL("http://maps.googleapis.com/maps/api/directions/json?origin=" + strings[0] + "," + strings[1] + "&destination=" + strings[2] + "," + strings[3] + "&sensor=false&units=metric&mode=driving&alternatives=true");
HttpURLConnection conn;
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("POST");
InputStream in;
in = new BufferedInputStream(conn.getInputStream());
StringBuilder buffer = new StringBuilder();
BufferedReader reader;
reader = new BufferedReader(new InputStreamReader(in));
String inputLine;
while ((inputLine = reader.readLine()) != null)
buffer.append(inputLine).append("\n");
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
Log.e("empty", "empty");
}
JsonResponse = buffer.toString();
Log.d("response", JsonResponse);
} catch (IOException e1) {
e1.printStackTrace();
}
return JsonResponse;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
pd.dismiss();
if(flag==1) {
new ParserTask().execute(result);
}}
}
private class ParserTask extends AsyncTask<String, Integer, List<List<HashMap<String, String>>>> {
private ArrayList<LatLng> points;
#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]);
DirectionJSONParser parser = new DirectionJSONParser();
// Starts parsing data
routes = parser.parse(jObject);
} catch (Exception e) {
e.printStackTrace();
}
return routes;
}
#Override
protected void onPostExecute(List<List<HashMap<String, String>>> result) {
PolylineOptions polylineOptionss=null;
// MarkerOptions markerOptions = new MarkerOptions();
// Traversing through all the routes
for (int i = 0; i < result.size(); i++) {
points = new ArrayList<>();
// 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);
if (j == 0) {
duration = point.get("duration");
Log.d("duration", duration);
continue;
}
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
polylineOptionss=new PolylineOptions();
// Adding all the points in the route to LineOptions
polylineOptionss.addAll(points);
// polylineOptions.width(7);
// Random rnd = new Random();
// int color = Color.argb(255, rnd.nextInt(256), rnd.nextInt(256), rnd.nextInt(256));
if(i==0) {
polylineOptions0=new PolylineOptions();
polylineOptions0.addAll(points);
// mGoogleMap.setTrafficEnabled(true);
polylineOptions0.width(15);
polylineOptions0.color(Color.parseColor("#9c27b0"));
polylineOptions0.geodesic(true);
Polyline polyline= mGoogleMap.addPolyline(polylineOptions0);
polyline.setTag(duration);
polyline.setClickable(true);
}
//Here only differentiating each and every route.
else if(i==1){
polylineOptions1=new PolylineOptions();
polylineOptions1.addAll(points);
polylineOptions1.geodesic(true);
polylineOptions1.width(15);
// mGoogleMap.setTrafficEnabled(true);
polylineOptions1.color(Color.parseColor("#9e9e9e"));
Polyline polyline= mGoogleMap.addPolyline(polylineOptions1);
polyline.setTag(duration);
polyline.setClickable(true);
///
}
else if(i==2){
polylineOptions2=new PolylineOptions();
polylineOptions2.addAll(points);
polylineOptions2.geodesic(true);
polylineOptions2.width(15);
polylineOptions2.color(Color.parseColor("#9c27b0"));
Polyline polyline= mGoogleMap.addPolyline(polylineOptions2);
polyline.setTag(duration);
polyline.setClickable(true);
// mGoogleMap.setTrafficEnabled(true);
//
}
else {
polylineOptions3=new PolylineOptions();
polylineOptions3.addAll(points);
// mGoogleMap.setTrafficEnabled(true);
polylineOptions3.width(15);
polylineOptions3.geodesic(true);
polylineOptions3.color(Color.parseColor("#9e9e9e"));
Polyline polyline= mGoogleMap.addPolyline(polylineOptions3);
polyline.setTag(duration);
polyline.setClickable(true);
/// polylineOptions3.color(Color.parseColor("#ffffff"));
}
}
setBottomSheet(jsonresponse, edt.getText().toString(),1);
CameraAnimation(polylineOptionss);
// mGoogleMap.addPolyline(polylineOptions);
// Drawing polyline in the Google Map for the i-th route
}
}
How to plot first route with one color from starting to end and then remaining routes with other color. Thanks in advance !!

Use Z-Index variable of Polyline and Use Polylineclick listener to change the z-index of the polylines. Means whenever you click any line, its z-index will be increased and other lines z-index will be decreased so that the line you clicked will always override others. See the attached code for help.
Z-Index
The order in which this tile overlay is drawn with respect to other overlays (including GroundOverlays, TileOverlays, Circles, and Polygons but not Markers). An overlay with a larger z-index is drawn over overlays with smaller z-indices. The order of overlays with the same z-index is arbitrary. The default zIndex is 0.
final List<Polyline> polylines = new ArrayList<>();
for(int i= 0; i<paths.size(); i++ ){
polylines.add(mMap.addPolyline(paths.get(i)));
}
mMap.setOnPolylineClickListener(new GoogleMap.OnPolylineClickListener() {
#Override
public void onPolylineClick(Polyline polyline) {
for(int i= 0; i<polylines.size(); i++ ){
polylines.get(i).setColor(Color.argb(255,187,189,191));
polylines.get(i).setZIndex(0);
}
polyline.setColor(Color.argb(255,102,157,246));
polyline.setZIndex(2);
}
});

One possible solution might be to vary the strokeWidth of the overlapping section of the polyline so that the first one drawn is wider and therefore can still be seen under the subsequent ones. Just an idea, not tested.

Google direction route from current location to known location

I use the MapsActivity class in this project. On my map you can see many markers. I have many known locations, but in my code I just display two locations for example.
I don't understand how to use the direction API and JSON. How can I display the route, distance, and travelling time from my current location (changing) to a known location (constant)?
public class MapsActivity extends FragmentActivity {
private GoogleMap mMap; // Might be null if Google Play services APK is not available.
private Map<Marker, Class<?>> allMarkersMap = new HashMap<Marker, Class<?>>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
setUpMapIfNeeded();
}
private void setUpMap() {
Marker marker1 = mMap.addMarker(new MarkerOptions()
.position(new LatLng(14.608177, 120.967422))
.title("Sample2")
.snippet("zzzzzzz"));
allMarkersMap.put(marker1, MainActivity.class);
Marker marker2 = mMap.addMarker(new MarkerOptions()
.position(new LatLng(14.611335, 120.962160))
.title("Sample1")
.snippet("sssssss"));
allMarkersMap.put(marker2, MainActivity2Activity.class);
mMap.setMyLocationEnabled(true);
mMap.setOnInfoWindowClickListener(new GoogleMap.OnInfoWindowClickListener() {
#Override
public void onInfoWindowClick(Marker marker) {
Class<?> cls = allMarkersMap.get(marker);
Intent intent = new Intent(MapsActivity.this, cls);
startActivity(intent);
}
});
}

Have a look at this tutorial:
Drawing driving route directions between two locations using Google Directions in Google Map Android API V2
It shows how to draw a route map between two points, calculate distance and travel time.
If you are having problems in following the tutorial, download the Android Studio sample project from the link below:
MapDemo.zip
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<LatLng> 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<LatLng> decodePoly(String encoded) {
List<LatLng> poly = new ArrayList<LatLng>();
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;
}
}
MainActivity.Java
public class MainActivity extends FragmentActivity {
GoogleMap map;
ArrayList<LatLng> markerPoints;
TextView tvDistanceDuration;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tvDistanceDuration = (TextView) findViewById(R.id.tv_distance_time);
// Initializing
markerPoints = new ArrayList<LatLng>();
// Getting reference to SupportMapFragment of the activity_main
SupportMapFragment fm = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
// Getting Map for the SupportMapFragment
map = fm.getMap();
// Enable MyLocation Button in the Map
map.setMyLocationEnabled(true);
// Setting onclick event listener for the map
map.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
#Override
public void onMapClick(LatLng point) {
// Already two locations
if (markerPoints.size() > 1) {
markerPoints.clear();
map.clear();
}
// Adding new item to the ArrayList
markerPoints.add(point);
// Creating MarkerOptions
MarkerOptions options = new MarkerOptions();
// Setting the position of the marker
options.position(point);
/**
* For the start location, the color of marker is GREEN and
* for the end location, the color of marker is RED.
*/
if (markerPoints.size() == 1) {
options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
} else if (markerPoints.size() == 2) {
options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
}
// Add new marker to the Google Map Android API V2
map.addMarker(options);
// Checks, whether start and end locations are captured
if (markerPoints.size() >= 2) {
LatLng origin = markerPoints.get(0);
LatLng dest = markerPoints.get(1);
// Getting URL to the Google Directions API
String url = getDirectionsUrl(origin, dest);
DownloadTask downloadTask = new DownloadTask();
// Start downloading json data from Google Directions API
downloadTask.execute(url);
}
}
});
}
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;
}
/**
* A method to download json data from url
*/
private String downloadUrl(String strUrl) throws IOException {
String data = "";
InputStream iStream = null;
HttpURLConnection urlConnection = null;
try {
URL url = new URL(strUrl);
// Creating an http connection to communicate with url
urlConnection = (HttpURLConnection) url.openConnection();
// Connecting to url
urlConnection.connect();
// Reading data from url
iStream = urlConnection.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(iStream));
StringBuffer sb = new StringBuffer();
String line = "";
while ((line = br.readLine()) != null) {
sb.append(line);
}
data = sb.toString();
br.close();
} catch (Exception e) {
Log.d("Exception while downloading url", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
// Fetches data from url passed
private class DownloadTask extends AsyncTask<String, Void, String> {
// Downloading data in non-ui thread
#Override
protected String doInBackground(String... url) {
// For storing data from web service
String data = "";
try {
// Fetching the data from web service
data = downloadUrl(url[0]);
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
return data;
}
// Executes in UI thread, after the execution of
// doInBackground()
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
ParserTask parserTask = new ParserTask();
// Invokes the thread for parsing the JSON data
parserTask.execute(result);
}
}
/**
* A class to parse the Google Places in JSON format
*/
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();
// Starts parsing data
routes = parser.parse(jObject);
} catch (Exception e) {
e.printStackTrace();
}
return routes;
}
// Executes in UI thread, after the parsing process
#Override
protected void onPostExecute(List<List<HashMap<String, String>>> result) {
ArrayList<LatLng> points = null;
PolylineOptions lineOptions = null;
MarkerOptions markerOptions = new MarkerOptions();
String distance = "";
String duration = "";
if (result.size() < 1) {
Toast.makeText(getBaseContext(), "No Points", Toast.LENGTH_SHORT).show();
return;
}
// 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);
if (j == 0) { // Get distance from the list
distance = (String) point.get("distance");
continue;
} else if (j == 1) { // Get duration from the list
duration = (String) point.get("duration");
continue;
}
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);
}
tvDistanceDuration.setText("Distance:" + distance + ", Duration:" + duration);
// Drawing polyline in the Google Map for the i-th route
map.addPolyline(lineOptions);
}
}

The code is for drawing the distance between any two points, start is the current location and the other is a location stored in the SQLite db.
public class MapsActivity extends FragmentActivity implements OnMapReadyCallback ,GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
private GoogleMap mMap;
ArrayList<LatLng> MarkerPoints;
GoogleApiClient mGoogleApiClient;
Location mLastLocation;
Marker mCurrLocationMarker;
LocationRequest mLocationRequest;
String lat, lon;
LatLng start;
LatLng dest;
String destlat;
String destlon;
public void setLat(String lat) {
this.lat = lat;
}
public void setLon(String lon) {
this.lon = lon;
}
public void setDestlat(String destlat) {
this.destlat = destlat;
}
public void setDestlon(String destlon) {
this.destlon = destlon;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
checkLocationPermission();
}
// Initializing
MarkerPoints = new ArrayList<>();
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
/**
* Manipulates the map once available.
* This callback is triggered when the map is ready to be used.
* This is where we can add markers or lines, add listeners or move the camera. In this case,
* we just add a marker near Sydney, Australia.
* If Google Play services is not installed on the device, the user will be prompted to install
* it inside the SupportMapFragment. This method will only be triggered once the user has
* installed Google Play services and returned to the app.
*/
#Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
Log.d("OnmapREady fired", "fired");
//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) {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
}
else {
buildGoogleApiClient();
mMap.setMyLocationEnabled(true);
}
}
public void mapOperations(){
Log.d("Map operations called","Hope");
LatLng point = start;
// Already two locations
if (MarkerPoints.size() > 1) {
MarkerPoints.clear();
mMap.clear();
}
// Adding new item to the ArrayList
MarkerPoints.add(start);
// adding destination from database
LocationsDB db = new LocationsDB(MapsActivity.this);
String loc = db.getTermValues();
Log.d("location from db",loc);
String[] separated = loc.split(" ");
//try {
Double lt = Double.parseDouble(separated[0]);
Double ln = Double.parseDouble(separated[1]);
dest = new LatLng(lt,ln);
MarkerPoints.add(dest);
//}
//catch(Exception e) {
// Log.d("Wrong target location", e.toString());
//}
// Creating MarkerOptions
MarkerOptions options = new MarkerOptions();
// Setting the position of the marker
options.position(start);
options.position(dest);
/**
* For the start location, the color of marker is GREEN and
* for the end location, the color of marker is RED.
*/
if (MarkerPoints.size() == 1) {
options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
} else if (MarkerPoints.size() == 2) {
options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED));
}
// Add new marker to the Google Map Android API V2
mMap.addMarker(options);
// Checks, whether start and end locations are captured
if (MarkerPoints.size() >= 2) {
LatLng origin = MarkerPoints.get(0);
LatLng dest = MarkerPoints.get(1);
// Getting URL to the Google Directions API
String url = getUrl(origin, dest);
Log.d("onMapClick", url.toString());
FetchUrl FetchUrl = new FetchUrl();
// Start downloading json data from Google Directions API
FetchUrl.execute(url);
//move map camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(origin));
mMap.animateCamera(CameraUpdateFactory.zoomTo(11));
}
}
private String getUrl(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;
}
/**
* A method to download json data from url
*/
private String downloadUrl(String strUrl) throws IOException {
String data = "";
InputStream iStream = null;
HttpURLConnection urlConnection = null;
try {
URL url = new URL(strUrl);
// Creating an http connection to communicate with url
urlConnection = (HttpURLConnection) url.openConnection();
// Connecting to url
urlConnection.connect();
// Reading data from url
iStream = urlConnection.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(iStream));
StringBuffer sb = new StringBuffer();
String line = "";
while ((line = br.readLine()) != null) {
sb.append(line);
}
data = sb.toString();
Log.d("downloadUrl", data.toString());
br.close();
} catch (Exception e) {
Log.d("Exception", e.toString());
} finally {
iStream.close();
urlConnection.disconnect();
}
return data;
}
// Fetches data from url passed
private class FetchUrl extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... url) {
// For storing data from web service
String data = "";
try {
// Fetching the data from web service
data = downloadUrl(url[0]);
Log.d("Background Task data", data.toString());
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
return data;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
ParserTask parserTask = new ParserTask();
// Invokes the thread for parsing the JSON data
parserTask.execute(result);
}
}
/**
* A class to parse the Google Places in JSON format
*/
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]);
Log.d("ParserTask",jsonData[0].toString());
DataParser parser = new DataParser();
Log.d("ParserTask", parser.toString());
// Starts parsing data
routes = parser.parse(jObject);
Log.d("ParserTask","Executing routes");
Log.d("ParserTask",routes.toString());
} catch (Exception e) {
Log.d("ParserTask",e.toString());
e.printStackTrace();
}
return routes;
}
// Executes in UI thread, after the parsing process
#Override
protected void onPostExecute(List<List<HashMap<String, String>>> result) {
ArrayList<LatLng> points;
PolylineOptions lineOptions = null;
// Traversing through all the routes
for (int i = 0; i < result.size(); i++) {
points = new ArrayList<>();
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(10);
lineOptions.color(Color.RED);
Log.d("onPostExecute","onPostExecute lineoptions decoded");
}
// Drawing polyline in the Google Map for the i-th route
if(lineOptions != null) {
mMap.addPolyline(lineOptions);
}
else {
Log.d("onPostExecute","without Polylines drawn");
}
}
}
protected synchronized void buildGoogleApiClient() {
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
#Override
public void onConnected(Bundle bundle) {
Log.d("OnConnected fired","fired");
mLocationRequest = new LocationRequest();
mLocationRequest.setInterval(1000);
mLocationRequest.setFastestInterval(1000);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
}
mLastLocation = LocationServices.FusedLocationApi.getLastLocation(
mGoogleApiClient);
if (mLastLocation != null) {
lat = String.valueOf(mLastLocation.getLatitude());
lon = String.valueOf(mLastLocation.getLongitude());
start = new LatLng(mLastLocation.getLatitude(),mLastLocation.getLongitude());
Toast.makeText(this,"Connected",Toast.LENGTH_SHORT).show();
mapOperations();
}
else{
Toast.makeText(this,"Failed",Toast.LENGTH_LONG).show();
}
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onLocationChanged(Location location) {
mLastLocation = location;
if (mCurrLocationMarker != null) {
mCurrLocationMarker.remove();
}
//Place current location marker
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(latLng);
markerOptions.title("Current Position");
markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));
mCurrLocationMarker = mMap.addMarker(markerOptions);
//move map camera
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(11));
//stop location updates
if (mGoogleApiClient != null) {
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
}
}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {
}
public static final int MY_PERMISSIONS_REQUEST_LOCATION = 99;
public boolean checkLocationPermission(){
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
// Asking user if explanation is needed
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.ACCESS_FINE_LOCATION)) {
// Show an explanation to the user *asynchronously* -- don't block
// this thread waiting for the user's response! After the user
// sees the explanation, try again to request the permission.
//Prompt the user once explanation has been shown
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
} else {
// No explanation needed, we can request the permission.
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
MY_PERMISSIONS_REQUEST_LOCATION);
}
return false;
} else {
return true;
}
}
#Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case MY_PERMISSIONS_REQUEST_LOCATION: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted. Do the
// contacts-related task you need to do.
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
if (mGoogleApiClient == null) {
buildGoogleApiClient();
}
mMap.setMyLocationEnabled(true);
}
} else {
// Permission denied, Disable the functionality that depends on this permission.
Toast.makeText(this, "permission denied", Toast.LENGTH_LONG).show();
}
return;
}
// other 'case' lines to check for other permissions this app might request.
// You can add here other case statements according to your requirement.
}
}
#Override
protected void onDestroy() {
super.onDestroy();
}
}
This is the code for finding and drawing the routes between the points.
public class DataParser {
/** 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<>() ;
JSONArray jRoutes;
JSONArray jLegs;
JSONArray jSteps;
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<>();
/** 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<LatLng> list = decodePoly(polyline);
/** Traversing all points */
for(int l=0;l<list.size();l++){
HashMap<String, String> hm = new HashMap<>();
hm.put("lat", Double.toString((list.get(l)).latitude) );
hm.put("lng", Double.toString((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<LatLng> decodePoly(String encoded) {
List<LatLng> 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;
}
}