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Show route in Google Maps API v2 on Android

I am trying to display a route between two MarkerOptions points in Android. I found this tutorial here that works well for me, but I'm trying to set it up so that MarkerOptions my current location and fixed LatLng object, and not the two points you get when you touch the map. So, I have the current location, LatLng = updatedLatLng , and fixed - LatLng = wcbcLatLng . In the tutorial, the onMapClick method looks like this:

  public void onTouchMap(){ // Setting onclick event listener for the map this.mapG3.setOnMapClickListener(new OnMapClickListener() { @Override public void onMapClick(LatLng point) { // Already two locations if (Geo4.this.markerPoints.size() > 1) { Geo4.this.markerPoints.clear(); Geo4.this.mapG3.clear(); } // Adding new item to the ArrayList Geo4.this.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 (Geo4.this.markerPoints.size() == 1) { options.icon(BitmapDescriptorFactory .defaultMarker (BitmapDescriptorFactory.HUE_GREEN)); } else if (Geo4.this.markerPoints.size() == 2) { options.icon(BitmapDescriptorFactory .defaultMarker (BitmapDescriptorFactory.HUE_RED)); } // Add new marker to the Google Map Android API V2 Geo4.this.mapG3.addMarker(options); // Checks, whether start and end locations are captured if (Geo4.this.markerPoints.size() >= 2) { LatLng origin = Geo4.this.markerPoints.get(0); LatLng dest = Geo4.this.markerPoints.get(1); // Getting URL to the Google Directions API String url = Geo4.this.getDirectionsUrl(origin, dest); DownloadTask downloadTask = new DownloadTask(); // Start downloading json data from Google Directions API downloadTask.execute(url); } } }); }//-- END Method

This is the method I want to change so that it updatedLatLng for my updatedLatLng and wcbcLatLng instead of the LatLng origin and LatLng dest that this method uses. Any help would be appreciated! Here is my full activity:

  import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.URL; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import org.json.JSONObject; import android.app.AlertDialog; import android.content.Intent; import android.graphics.Color; import android.location.LocationManager; import android.os.AsyncTask; import android.os.Bundle; import android.support.v4.app.FragmentActivity; import android.util.Log; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.Button; import android.widget.TextView; import android.widget.Toast; import com.google.android.gms.common.GooglePlayServicesUtil; import com.google.android.gms.maps.CameraUpdate; import com.google.android.gms.maps.CameraUpdateFactory; import com.google.android.gms.maps.GoogleMap; import com.google.android.gms.maps.GoogleMap.OnMapClickListener; import com.google.android.gms.maps.SupportMapFragment; import com.google.android.gms.maps.model.BitmapDescriptorFactory; import com.google.android.gms.maps.model.LatLng; import com.google.android.gms.maps.model.LatLngBounds; import com.google.android.gms.maps.model.Marker; import com.google.android.gms.maps.model.MarkerOptions; import com.google.android.gms.maps.model.PolylineOptions; import android.location.Criteria; import android.location.Location; import android.location.LocationListener; import android.location.LocationManager; import android.provider.Settings; public class Geo4 extends FragmentActivity implements LocationListener { GoogleMap mapG3; ArrayList<LatLng> markerPoints; TextView mapInfo_TV; LocationManager locMan; SupportMapFragment sMf; Button back_btn, zoom_btn; MarkerOptions startMO, wcbcMO, broncoMO; MarkerOptions markers; Marker currentMarker, wcbcMarker, broncoMarker; LatLng updatedLatLng, directionsLatLng; LatLng wcbcLatLng = new LatLng(30.393903, -97.682871); LatLng oskiLatLng = new LatLng(30.474570, -97.973889); LatLng point, point3t, point4t; CameraUpdate cameraUpdate; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.geo3); back_btn = (Button) findViewById(R.id.backMap_g3_btn); zoom_btn = (Button) findViewById(R.id.marker_g3_btn); this.mapInfo_TV = (TextView) this.findViewById(R.id.map_g3Info_TV); // Initializing this.markerPoints = new ArrayList<LatLng>(); // Getting reference to SupportMapFragment of the activity_main sMf = (SupportMapFragment) this.getSupportFragmentManager() .findFragmentById(R.id.map_g3_FRAG); // Getting Map for the SupportMapFragment this.mapG3 = sMf.getMap(); // --- fire Methods googlePlay(); getCurrentLocation(); onTouchMap(); // --- END fire Methods // --- Back button back_btn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View arg0) { // mapG3.clear(); Intent backmapI = new Intent( "com.my.package.BUTTON_INTERFACE"); startActivity(backmapI); } }); // --- end Back button // --- Zoom button zoom_btn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View arg0) { getDirections4T(point4t); } }); // --- end Zoom button }// --- END onCreate // --- Methods ---- public void googlePlay() { // ---- Google Play // Getting Google Play availability status int status = GooglePlayServicesUtil .isGooglePlayServicesAvailable(getBaseContext()); if (status != ConnectionResult.SUCCESS) { // Google Play Services are // not available int requestCode = 10; Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this, requestCode); dialog.show(); } else { // Google Play Services are available //Toast.makeText(getApplicationContext(),"Services Launched Fo Sho'",Toast.LENGTH_SHORT).show(); } } // ---- END Method public void getCurrentLocation(){ // Getting LocationManager object from System Service LOCATION_SERVICE locMan = (LocationManager) getSystemService(LOCATION_SERVICE); boolean enabledGPS = locMan .isProviderEnabled(LocationManager.GPS_PROVIDER); boolean enabledWiFi = locMan .isProviderEnabled(LocationManager.NETWORK_PROVIDER); // Check if enabled and if not send user to the GPS settings if (!enabledGPS && !enabledWiFi) { Toast.makeText(getApplicationContext(), "GPS signal not found", Toast.LENGTH_LONG).show(); Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS); startActivity(intent); } // Creating a criteria object to retrieve provider Criteria criteria = new Criteria(); // Getting the name of the best provider String provider = locMan.getBestProvider(criteria, true); // Getting Current Location From GPS Location oLc = locMan.getLastKnownLocation(provider); if (oLc != null) { onLocationChanged(oLc); } locMan.requestLocationUpdates(provider, 20000, 0, this); }//--- END Method public void zoomToFit() { // --- zoom to fit LatLngBounds.Builder builder = new LatLngBounds.Builder(); builder.include(wcbcLatLng); builder.include(updatedLatLng); LatLngBounds bounds = builder.build(); int padding = 50; // offset from edges of the map in pixels cameraUpdate = CameraUpdateFactory.newLatLngBounds(bounds, padding); mapG3.animateCamera(cameraUpdate); // --- END zoom to fit }// --- END Method public void addwcbcMarkerOption() { wcbcMO = new MarkerOptions().position(wcbcLatLng).title( "Destination"); wcbcMO.icon(BitmapDescriptorFactory .defaultMarker(BitmapDescriptorFactory.HUE_VIOLET)); mapG3.addMarker(wcbcMO); cameraUpdate = CameraUpdateFactory.newLatLngZoom(wcbcLatLng, 15); mapG3.animateCamera(cameraUpdate); }// --- END Method public void getDirections4T(LatLng point4t) { Geo4.this.markerPoints.add(point4t); markers = new MarkerOptions(); markers.position(wcbcLatLng); markers.position(oskiLatLng); if (Geo4.this.markerPoints.size() == 1) { markers.icon(BitmapDescriptorFactory .defaultMarker(BitmapDescriptorFactory.HUE_GREEN)); } else if (Geo4.this.markerPoints.size() == 2) { markers.icon(BitmapDescriptorFactory .defaultMarker(BitmapDescriptorFactory.HUE_RED)); } Geo4.this.mapG3.addMarker(markers); }//--- END Method public void onTouchMap(){ // Setting onclick event listener for the map this.mapG3.setOnMapClickListener(new OnMapClickListener() { @Override public void onMapClick(LatLng point) { // Already two locations if (Geo4.this.markerPoints.size() > 1) { Geo4.this.markerPoints.clear(); Geo4.this.mapG3.clear(); } // Adding new item to the ArrayList Geo4.this.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 (Geo4.this.markerPoints.size() == 1) { options.icon(BitmapDescriptorFactory .defaultMarker (BitmapDescriptorFactory.HUE_GREEN)); } else if (Geo4.this.markerPoints.size() == 2) { options.icon(BitmapDescriptorFactory .defaultMarker (BitmapDescriptorFactory.HUE_RED)); } // Add new marker to the Google Map Android API V2 Geo4.this.mapG3.addMarker(options); // Checks, whether start and end locations are captured if (Geo4.this.markerPoints.size() >= 2) { LatLng origin = Geo4.this.markerPoints.get(0); LatLng dest = Geo4.this.markerPoints.get(1); // Getting URL to the Google Directions API String url = Geo4.this.getDirectionsUrl(origin, dest); DownloadTask downloadTask = new DownloadTask(); // Start downloading json data from Google Directions API downloadTask.execute(url); } } }); }//-- END Method private String getDirectionsUrl(LatLng updatedLatLng, LatLng dest) { // Origin of route String str_updatedLatLng = "origin=" + updatedLatLng.latitude + "," + updatedLatLng.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_updatedLatLng + "&" + 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 = Geo4.this.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]); Geo3JSON parser = new Geo3JSON(); // 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(Geo4.this.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 = point.get("distance"); continue; } else if (j == 1) { // Get duration from the list duration = 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(4); lineOptions.color(Color.RED); } Geo4.this.mapInfo_TV.setText("Distance: " + distance + "les"); // Drawing polyline in the Google Map for the route Geo4.this.mapG3.addPolyline(lineOptions); } } // --- END Methods // --- onLocationListener @Override public void onLocationChanged(Location oLc) { updatedLatLng = new LatLng(oLc.getLatitude(), oLc.getLongitude()); startMO = new MarkerOptions().position(updatedLatLng) .title("You Are Here") .icon(BitmapDescriptorFactory .defaultMarker(BitmapDescriptorFactory.HUE_ORANGE)); mapG3.addMarker(startMO); addwcbcMarkerOption(); locMan.removeUpdates(this); } @Override public void onProviderDisabled(String provider) { // } @Override public void onProviderEnabled(String provider) { // } @Override public void onStatusChanged(String provider, int status, Bundle extras) { // } // --- END onLocationListener @Override protected void onPause() { super.onPause(); overridePendingTransition(R.anim.fadein, R.anim.fadeout); finish(); } // --- inflated menu @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.wcbcv, menu); return true; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.menu_legalnotices: String LicenseInfo = GooglePlayServicesUtil .getOpenSourceSoftwareLicenseInfo(getApplicationContext ()); AlertDialog.Builder LicenseDialog = new AlertDialog.Builder( Geo4.this); LicenseDialog.setTitle("Legal Notices"); LicenseDialog.setMessage(LicenseInfo); LicenseDialog.show(); return true; } return super.onOptionsItemSelected(item); } // --- END inflated menu }
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I understood that. Most of my onTouchMap() get onTouch info and convert these integers to LatLng values. Since I already have LatLng values, I only need the last three lines of the method, which take LatLng and receive JSON data from them. So I rewrote the method to add MarkerOptions and LatLng values MarkerOptions , then I added the last 3 lines from the old method. So, what my new method looks like and it works correctly (by calling 3 other methods) and draws a polyline and displays the distance in miles in the TextView .

  public void addMarkers(){ wcbcMO = new MarkerOptions().position(wcbcLatLng) .title("Destination") .icon(BitmapDescriptorFactory .defaultMarker(BitmapDescriptorFactory.HUE_VIOLET)); mapG3.addMarker(wcbcMO); startMO = new MarkerOptions().position(updatedLatLng) .title("You Are Here") .icon(BitmapDescriptorFactory .defaultMarker(BitmapDescriptorFactory.HUE_ORANGE)); mapG3.addMarker(startMO); // Getting URL to the Google Directions API String url = Geo4.this.getDirectionsUrl(updatedLatLng, wcbcLatLng); DownloadTask downloadTask = new DownloadTask(); // Start downloading json data from Google Directions API downloadTask.execute(url); }//--- END Method
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 public class MainActivity extends Activity { static final LatLng HAMBURG = new LatLng(53.558, 9.927); static final LatLng KIEL = new LatLng(53.551, 9.993); private GoogleMap map; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); map = ((MapFragment) getFragmentManager().findFragmentById(R.id.map)) .getMap(); Marker hamburg = map.addMarker(new MarkerOptions().position(HAMBURG) .title("Hamburg")); Marker kiel = map.addMarker(new MarkerOptions() .position(KIEL) .title("Kiel") .snippet("Kiel is cool") .icon(BitmapDescriptorFactory .fromResource(R.drawable.ic_launcher))); map.moveCamera(CameraUpdateFactory.newLatLngZoom(HAMBURG, 15)); map.setMyLocationEnabled(true); map.animateCamera(CameraUpdateFactory.zoomTo(10), 2000, null); map.setOnMapClickListener(new OnMapClickListener() { private double latitude; private double longitude; @Override public void onMapClick(LatLng arg0) { latitude = arg0.latitude; longitude = arg0.longitude; StringBuilder result = new StringBuilder(); try { Geocoder geocoder = new Geocoder(MainActivity.this, Locale .getDefault()); List<Address> addresses = geocoder.getFromLocation( latitude, longitude, 1); if (addresses.size() > 0) { Address address = addresses.get(0); result.append(address.getLocality()).append("\n"); result.append(address.getCountryName()); Toast.makeText(getApplicationContext(), result, 3000) .show(); } } catch (IOException e) { Log.e("tag", e.getMessage()); } } }); } public String makeURL (double sourcelat, double sourcelog, double destlat, double destlog ){ StringBuilder urlString = new StringBuilder(); urlString.append("http://maps.googleapis.com/maps/api/directions/json"); urlString.append("?origin=");// from urlString.append(Double.toString(sourcelat)); urlString.append(","); urlString .append(Double.toString( sourcelog)); urlString.append("&destination=");// to urlString .append(Double.toString( destlat)); urlString.append(","); urlString.append(Double.toString( destlog)); urlString.append("&sensor=false&mode=driving&alternatives=true"); return urlString.toString(); } public class JSONParser { InputStream is = null; JSONObject jObj = null; String json = ""; public JSONParser() { } public String getJSONFromUrl(String url) { try { DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); HttpResponse httpResponse = httpClient.execute(httpPost); HttpEntity httpEntity = httpResponse.getEntity(); is = httpEntity.getContent(); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } catch (ClientProtocolException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } try { BufferedReader reader = new BufferedReader(new InputStreamReader( is, "iso-8859-1"), 8); StringBuilder sb = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } json = sb.toString(); is.close(); } catch (Exception e) { Log.e("Buffer Error", "Error converting result " + e.toString()); } return json; } } private String url; JSONParser jParser = new JSONParser(); String json = jParser.getJSONFromUrl(url); public void drawPath(String result) { try { 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); for(int z = 0; z<list.size()-1;z++){ LatLng src= list.get(z); LatLng dest= list.get(z+1); Polyline line = map.addPolyline(new PolylineOptions() .add(new LatLng(src.latitude, src.longitude), new LatLng(dest.latitude, dest.longitude)) .width(2) .color(Color.BLUE).geodesic(true)); } } catch (JSONException e) { } } 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; } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.main, menu); return true; } }
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