Develop Reference

how to draw different paths between locations in google map? [duplicate]

I've been busy for a long time finding out how to draw a line between two (GPS) points on the map in HelloMapView but with no luck.
Could anyone please tell me how to do so.
Suppose I use the HelloMapView which extends MapView. Do I need to use overlays? If so do I have to override the onDraw() method of the overlay and draw a line here? I actually tried these things but with no result.
Thank you in advance!

Thank you for your help. At last I could draw a line on the map.
This is how I done it:
/** Called when the activity is first created. */
private List<Overlay> mapOverlays;
private Projection projection;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
linearLayout = (LinearLayout) findViewById(R.id.zoomview);
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
mapOverlays = mapView.getOverlays();
projection = mapView.getProjection();
mapOverlays.add(new MyOverlay());
}
#Override
protected boolean isRouteDisplayed() {
return false;
}
class MyOverlay extends Overlay{
public MyOverlay(){
}
public void draw(Canvas canvas, MapView mapv, boolean shadow){
super.draw(canvas, mapv, shadow);
Paint mPaint = new Paint();
mPaint.setDither(true);
mPaint.setColor(Color.RED);
mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(2);
GeoPoint gP1 = new GeoPoint(19240000,-99120000);
GeoPoint gP2 = new GeoPoint(37423157, -122085008);
Point p1 = new Point();
Point p2 = new Point();
Path path = new Path();
Projection projection=mapv.getProjection();
projection.toPixels(gP1, p1);
projection.toPixels(gP2, p2);
path.moveTo(p2.x, p2.y);
path.lineTo(p1.x,p1.y);
canvas.drawPath(path, mPaint);
}

For those who really only want to draw a simple line - there is indeed also the short short version.
GoogleMap map;
// ... get a map.
// Add a thin red line from London to New York.
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(51.5, -0.1), new LatLng(40.7, -74.0))
.width(5)
.color(Color.RED));
from https://developers.google.com/maps/documentation/android/reference/com/google/android/gms/maps/model/Polyline

// This Activity will draw a line between two selected points on Map
public class MainActivity extends MapActivity {
MapView myMapView = null;
MapController myMC = null;
GeoPoint geoPoint = null;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myMapView = (MapView) findViewById(R.id.mapview);
geoPoint = null;
myMapView.setSatellite(false);
String pairs[] = getDirectionData("ahmedabad", "vadodara");
String[] lngLat = pairs[0].split(",");
// STARTING POINT
GeoPoint startGP = new GeoPoint(
(int) (Double.parseDouble(lngLat[1]) * 1E6), (int) (Double
.parseDouble(lngLat[0]) * 1E6));
myMC = myMapView.getController();
geoPoint = startGP;
myMC.setCenter(geoPoint);
myMC.setZoom(15);
myMapView.getOverlays().add(new DirectionPathOverlay(startGP, startGP));
// NAVIGATE THE PATH
GeoPoint gp1;
GeoPoint gp2 = startGP;
for (int i = 1; i < pairs.length; i++) {
lngLat = pairs[i].split(",");
gp1 = gp2;
// watch out! For GeoPoint, first:latitude, second:longitude
gp2 = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6),
(int) (Double.parseDouble(lngLat[0]) * 1E6));
myMapView.getOverlays().add(new DirectionPathOverlay(gp1, gp2));
Log.d("xxx", "pair:" + pairs[i]);
}
// END POINT
myMapView.getOverlays().add(new DirectionPathOverlay(gp2, gp2));
myMapView.getController().animateTo(startGP);
myMapView.setBuiltInZoomControls(true);
myMapView.displayZoomControls(true);
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private String[] getDirectionData(String srcPlace, String destPlace) {
String urlString = "http://maps.google.com/maps?f=d&hl=en&saddr="
+ srcPlace + "&daddr=" + destPlace
+ "&ie=UTF8&0&om=0&output=kml";
Log.d("URL", urlString);
Document doc = null;
HttpURLConnection urlConnection = null;
URL url = null;
String pathConent = "";
try {
url = new URL(urlString.toString());
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = db.parse(urlConnection.getInputStream());
} catch (Exception e) {
}
NodeList nl = doc.getElementsByTagName("LineString");
for (int s = 0; s < nl.getLength(); s++) {
Node rootNode = nl.item(s);
NodeList configItems = rootNode.getChildNodes();
for (int x = 0; x < configItems.getLength(); x++) {
Node lineStringNode = configItems.item(x);
NodeList path = lineStringNode.getChildNodes();
pathConent = path.item(0).getNodeValue();
}
}
String[] tempContent = pathConent.split(" ");
return tempContent;
}
}
//*****************************************************************************
DirectionPathOverlay
public class DirectionPathOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
public DirectionPathOverlay(GeoPoint gp1, GeoPoint gp2) {
this.gp1 = gp1;
this.gp2 = gp2;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
Projection projection = mapView.getProjection();
if (shadow == false) {
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
paint.setColor(Color.BLUE);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(2);
canvas.drawLine((float) point.x, (float) point.y, (float) point2.x,
(float) point2.y, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
}
}

This is full source code to draw direction path from source latitude and longitude to destination latitude and longitude. I have changed the above code to fit for latitude and longitude rather than source and destination.
So anyone who is accessing his latitude and longitude through his gps can get the direction from his gps device to the destination coordinates.
Thanks to above answers we could make such a change and get path direction.
public class DrawMapActivity extends MapActivity {
MapView myMapView = null;
MapController myMC = null;
GeoPoint geoPoint = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myMapView = (MapView) findViewById(R.id.mapview);
geoPoint = null;
myMapView.setSatellite(false);
double fromLat = 12.303534;
double fromLong = 76.64611;
double toLat = 12.9715987;
double toLong = 77.5945627;
String sourceLat = Double.toString(fromLat);
String sourceLong = Double.toString(fromLong);
String destinationLat = Double.toString(toLat);
String destinationLong = Double.toString(toLong);
String pairs[] = getDirectionData(sourceLat,sourceLong, destinationLat, destinationLong );
String[] lngLat = pairs[0].split(",");
// STARTING POINT
GeoPoint startGP = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6), (int) (Double.parseDouble(lngLat[0]) * 1E6));
myMC = myMapView.getController();
geoPoint = startGP;
myMC.setCenter(geoPoint);
myMC.setZoom(10);
myMapView.getOverlays().add(new DirectionPathOverlay(startGP, startGP));
// NAVIGATE THE PATH
GeoPoint gp1;
GeoPoint gp2 = startGP;
for (int i = 1; i < pairs.length; i++) {
lngLat = pairs[i].split(",");
gp1 = gp2;
// watch out! For GeoPoint, first:latitude, second:longitude
gp2 = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6),(int) (Double.parseDouble(lngLat[0]) * 1E6));
myMapView.getOverlays().add(new DirectionPathOverlay(gp1, gp2));
Log.d("xxx", "pair:" + pairs[i]);
}
// END POINT
myMapView.getOverlays().add(new DirectionPathOverlay(gp2, gp2));
myMapView.getController().animateTo(startGP);
myMapView.setBuiltInZoomControls(true);
myMapView.displayZoomControls(true);
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private String[] getDirectionData(String sourceLat, String sourceLong, String destinationLat, String destinationLong) {
String urlString = "http://maps.google.com/maps?f=d&hl=en&" +"saddr="+sourceLat+","+sourceLong+"&daddr="+destinationLat+","+destinationLong + "&ie=UTF8&0&om=0&output=kml";
Log.d("URL", urlString);
Document doc = null;
HttpURLConnection urlConnection = null;
URL url = null;
String pathConent = "";
try {
url = new URL(urlString.toString());
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = db.parse(urlConnection.getInputStream());
} catch (Exception e) {
}
NodeList nl = doc.getElementsByTagName("LineString");
for (int s = 0; s < nl.getLength(); s++) {
Node rootNode = nl.item(s);
NodeList configItems = rootNode.getChildNodes();
for (int x = 0; x < configItems.getLength(); x++) {
Node lineStringNode = configItems.item(x);
NodeList path = lineStringNode.getChildNodes();
pathConent = path.item(0).getNodeValue();
}
}
String[] tempContent = pathConent.split(" ");
return tempContent;
}
}
//*****************************************************************************
class DirectionPathOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
public DirectionPathOverlay(GeoPoint gp1, GeoPoint gp2) {
this.gp1 = gp1;
this.gp2 = gp2;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
Projection projection = mapView.getProjection();
if (shadow == false) {
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
paint.setColor(Color.BLUE);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(2);
canvas.drawLine((float) point.x, (float) point.y, (float) point2.x,(float) point2.y, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
}
}
Hope it helps for other Stack Overflow users

This can be done by using intents too:
final Intent intent = new Intent(Intent.ACTION_VIEW,
Uri.parse(
"http://maps.google.com/maps?" +
"saddr="+YOUR_START_LONGITUDE+","+YOUR_START_LATITUDE+"&daddr="YOUR_END_LONGITUDE+","+YOUR_END_LATITUDE));
intent.setClassName(
"com.google.android.apps.maps",
"com.google.android.maps.MapsActivity");
startActivity(intent);

It is really easy with Google Maps Android API v2
Just copy the example from Developer documentation
(of course you have to init your map first)
GoogleMap map;
// ... get a map.
// Add a thin red line from London to New York.
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(51.5, -0.1), new LatLng(40.7, -74.0))
.width(5)
.color(Color.RED));

Yes you need to use overlays.
You need to get the MapView's overlays and add your new overlay onto it.
Your class extends Overlay, which is a transparent canvas in which you can draw on it like any other canvas.
You can use mapView.getProjection() to get projection of map view.
...
More info found here: http://blogoscoped.com/archive/2008-12-15-n14.html

You can get the projection from the MapView object which is passed into the draw() method:
mapv.getProjection().toPixels(gP1, p1);

public class MainActivity extends FragmentActivity {
List<Overlay> mapOverlays;
GeoPoint point1, point2;
LocationManager locManager;
Drawable drawable;
Document document;
GMapV2GetRouteDirection v2GetRouteDirection;
LatLng fromPosition;
LatLng toPosition;
GoogleMap mGoogleMap;
MarkerOptions markerOptions;
Location location ;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
v2GetRouteDirection = new GMapV2GetRouteDirection();
SupportMapFragment supportMapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mGoogleMap = supportMapFragment.getMap();
// Enabling MyLocation in Google Map
mGoogleMap.setMyLocationEnabled(true);
mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
mGoogleMap.getUiSettings().setCompassEnabled(true);
mGoogleMap.getUiSettings().setMyLocationButtonEnabled(true);
mGoogleMap.getUiSettings().setAllGesturesEnabled(true);
mGoogleMap.setTrafficEnabled(true);
mGoogleMap.animateCamera(CameraUpdateFactory.zoomTo(12));
markerOptions = new MarkerOptions();
fromPosition = new LatLng(11.663837, 78.147297);
toPosition = new LatLng(11.723512, 78.466287);
GetRouteTask getRoute = new GetRouteTask();
getRoute.execute();
}
/**
*
* #author VIJAYAKUMAR M
* This class Get Route on the map
*
*/
private class GetRouteTask extends AsyncTask<String, Void, String> {
private ProgressDialog Dialog;
String response = "";
#Override
protected void onPreExecute() {
Dialog = new ProgressDialog(MainActivity.this);
Dialog.setMessage("Loading route...");
Dialog.show();
}
#Override
protected String doInBackground(String... urls) {
//Get All Route values
document = v2GetRouteDirection.getDocument(fromPosition, toPosition, GMapV2GetRouteDirection.MODE_DRIVING);
response = "Success";
return response;
}
#Override
protected void onPostExecute(String result) {
mGoogleMap.clear();
if(response.equalsIgnoreCase("Success")){
ArrayList<LatLng> directionPoint = v2GetRouteDirection.getDirection(document);
PolylineOptions rectLine = new PolylineOptions().width(10).color(
Color.RED);
for (int i = 0; i < directionPoint.size(); i++) {
rectLine.add(directionPoint.get(i));
}
// Adding route on the map
mGoogleMap.addPolyline(rectLine);
markerOptions.position(toPosition);
markerOptions.draggable(true);
mGoogleMap.addMarker(markerOptions);
}
Dialog.dismiss();
}
}
#Override
protected void onStop() {
super.onStop();
finish();
}
}
Route Helper class
public class GMapV2GetRouteDirection {
public final static String MODE_DRIVING = "driving";
public final static String MODE_WALKING = "walking";
public GMapV2GetRouteDirection() { }
public Document getDocument(LatLng start, LatLng end, String mode) {
String url = "http://maps.googleapis.com/maps/api/directions/xml?"
+ "origin=" + start.latitude + "," + start.longitude
+ "&destination=" + end.latitude + "," + end.longitude
+ "&sensor=false&units=metric&mode=driving";
try {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
HttpResponse response = httpClient.execute(httpPost, localContext);
InputStream in = response.getEntity().getContent();
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(in);
return doc;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public String getDurationText (Document doc) {
NodeList nl1 = doc.getElementsByTagName("duration");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "text"));
Log.i("DurationText", node2.getTextContent());
return node2.getTextContent();
}
public int getDurationValue (Document doc) {
NodeList nl1 = doc.getElementsByTagName("duration");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "value"));
Log.i("DurationValue", node2.getTextContent());
return Integer.parseInt(node2.getTextContent());
}
public String getDistanceText (Document doc) {
NodeList nl1 = doc.getElementsByTagName("distance");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "text"));
Log.i("DistanceText", node2.getTextContent());
return node2.getTextContent();
}
public int getDistanceValue (Document doc) {
NodeList nl1 = doc.getElementsByTagName("distance");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "value"));
Log.i("DistanceValue", node2.getTextContent());
return Integer.parseInt(node2.getTextContent());
}
public String getStartAddress (Document doc) {
NodeList nl1 = doc.getElementsByTagName("start_address");
Node node1 = nl1.item(0);
Log.i("StartAddress", node1.getTextContent());
return node1.getTextContent();
}
public String getEndAddress (Document doc) {
NodeList nl1 = doc.getElementsByTagName("end_address");
Node node1 = nl1.item(0);
Log.i("StartAddress", node1.getTextContent());
return node1.getTextContent();
}
public String getCopyRights (Document doc) {
NodeList nl1 = doc.getElementsByTagName("copyrights");
Node node1 = nl1.item(0);
Log.i("CopyRights", node1.getTextContent());
return node1.getTextContent();
}
public ArrayList<LatLng> getDirection (Document doc) {
NodeList nl1, nl2, nl3;
ArrayList<LatLng> listGeopoints = new ArrayList<LatLng>();
nl1 = doc.getElementsByTagName("step");
if (nl1.getLength() > 0) {
for (int i = 0; i < nl1.getLength(); i++) {
Node node1 = nl1.item(i);
nl2 = node1.getChildNodes();
Node locationNode = nl2.item(getNodeIndex(nl2, "start_location"));
nl3 = locationNode.getChildNodes();
Node latNode = nl3.item(getNodeIndex(nl3, "lat"));
double lat = Double.parseDouble(latNode.getTextContent());
Node lngNode = nl3.item(getNodeIndex(nl3, "lng"));
double lng = Double.parseDouble(lngNode.getTextContent());
listGeopoints.add(new LatLng(lat, lng));
locationNode = nl2.item(getNodeIndex(nl2, "polyline"));
nl3 = locationNode.getChildNodes();
latNode = nl3.item(getNodeIndex(nl3, "points"));
ArrayList<LatLng> arr = decodePoly(latNode.getTextContent());
for(int j = 0 ; j < arr.size() ; j++) {
listGeopoints.add(new LatLng(arr.get(j).latitude, arr.get(j).longitude));
}
locationNode = nl2.item(getNodeIndex(nl2, "end_location"));
nl3 = locationNode.getChildNodes();
latNode = nl3.item(getNodeIndex(nl3, "lat"));
lat = Double.parseDouble(latNode.getTextContent());
lngNode = nl3.item(getNodeIndex(nl3, "lng"));
lng = Double.parseDouble(lngNode.getTextContent());
listGeopoints.add(new LatLng(lat, lng));
}
}
return listGeopoints;
}
private int getNodeIndex(NodeList nl, String nodename) {
for(int i = 0 ; i < nl.getLength() ; i++) {
if(nl.item(i).getNodeName().equals(nodename))
return i;
}
return -1;
}
private ArrayList<LatLng> decodePoly(String encoded) {
ArrayList<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 position = new LatLng((double) lat / 1E5, (double) lng / 1E5);
poly.add(position);
}
return poly;
}
}

just i will find draw with some rectangle in mapview just we want change paint as we like
EmptyOverlay.java
public class EmptyOverlay extends Overlay {
private float x1,y1;
private MapExampleActivity mv = null;
private Overlay overlay = null;
public EmptyOverlay(MapExampleActivity mapV){
mv = mapV;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
return super.draw(canvas, mapView, shadow, when);
}
#Override
public boolean onTouchEvent(MotionEvent e, MapView mapView) {
if(mv.isEditMode()){
if(e.getAction() == MotionEvent.ACTION_DOWN){
//when user presses the map add a new overlay to the map
//move events will be catched by newly created overlay
x1 = y1 = 0;
x1 = e.getX();
y1 = e.getY();
overlay = new MapOverlay(mv, x1, y1);
mapView.getOverlays().add(overlay);
}
if(e.getAction() == MotionEvent.ACTION_MOVE){
}
//---when user lifts his finger---
if (e.getAction() == MotionEvent.ACTION_UP) {
}
return true;
}
return false;
}
}
MapExampleActivity.java
public class MapExampleActivity extends MapActivity {
private MapView mapView;
private boolean isEditMode = false;
private Button toogle;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
toogle = (Button)findViewById(R.id.toogleMap);
toogle.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
toogleEditMode();
}
});
mapView = (MapView)findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true); //display zoom controls
//add one empty overlay acting as a overlay loader. This will catch press events and will add the actual overlays
mapView.getOverlays().add(new EmptyOverlay(this));
mapView.postInvalidate();
}
//toogle edit mode for drawing or navigating the map
private void toogleEditMode(){
isEditMode = !isEditMode;
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
#Override
protected boolean isLocationDisplayed() {
return false;
}
public boolean isEditMode(){
return this.isEditMode;
}
public MapView getMapView(){
return this.mapView;
}
}
MapOverlay.java
public class MapOverlay extends Overlay {
private float x1,y1,x2,y2;
private GeoPoint p1=null,p2=null;
private MapExampleActivity mv = null;
private Paint paint = new Paint();
private boolean isUp = false;
//constructor receiving the initial point
public MapOverlay(MapExampleActivity mapV,float x,float y){
paint.setStrokeWidth(2.0f);
x1 = x;
y1 = y;
mv = mapV;
p1 = mapV.getMapView().getProjection().fromPixels((int)x1,(int)y1);
}
//override draw method to add our custom drawings
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
if(p1 != null && p2 != null){
//get the 2 geopoints defining the area and transform them to pixels
//this way if we move or zoom the map rectangle will follow accordingly
Point screenPts1 = new Point();
mapView.getProjection().toPixels(p1, screenPts1);
Point screenPts2 = new Point();
mapView.getProjection().toPixels(p2, screenPts2);
//draw inner rectangle
paint.setColor(0x4435EF56);
paint.setStyle(Style.FILL);
canvas.drawRect(screenPts1.x, screenPts1.y, screenPts2.x, screenPts2.y, paint);
//draw outline rectangle
paint.setColor(0x88158923);
paint.setStyle(Style.STROKE);
canvas.drawRect(screenPts1.x, screenPts1.y, screenPts2.x, screenPts2.y, paint);
}
return true;
}
#Override
public boolean onTouchEvent(MotionEvent e, MapView mapView) {
if(mv.isEditMode() && !isUp){
if(e.getAction() == MotionEvent.ACTION_DOWN){
x1 = y1 = 0;
x1 = e.getX();
y1 = e.getY();
p1 = mapView.getProjection().fromPixels((int)x1,(int)y1);
}
//here we constantly change geopoint p2 as we move out finger
if(e.getAction() == MotionEvent.ACTION_MOVE){
x2 = e.getX();
y2 = e.getY();
p2 = mapView.getProjection().fromPixels((int)x2,(int)y2);
}
//---when user lifts his finger---
if (e.getAction() == MotionEvent.ACTION_UP) {
isUp = true;
}
return true;
}
return false;
}
}
see this http://n3vrax.wordpress.com/2011/08/13/drawing-overlays-on-android-map-view/

Try this one:
Add itemizedOverlay class:
public class AndroidGoogleMapsActivity extends MapActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Displaying Zooming controls
MapView mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
MapController mc = mapView.getController();
double lat = Double.parseDouble("48.85827758964043");
double lon = Double.parseDouble("2.294543981552124");
GeoPoint geoPoint = new GeoPoint((int)(lat * 1E6), (int)(lon * 1E6));
mc.animateTo(geoPoint);
mc.setZoom(15);
mapView.invalidate();
/**
* Placing Marker
* */
List<Overlay> mapOverlays = mapView.getOverlays();
Drawable drawable = this.getResources().getDrawable(R.drawable.mark_red);
AddItemizedOverlay itemizedOverlay =
new AddItemizedOverlay(drawable, this);
OverlayItem overlayitem = new OverlayItem(geoPoint, "Hello", "Sample Overlay item");
itemizedOverlay.addOverlay(overlayitem);
mapOverlays.add(itemizedOverlay);
}
#Override
protected boolean isRouteDisplayed() {
return false;
}
}

Simply get route form this url and do next ...
Origin ---> starting point latitude & longitude
Destination---> ending point latitude & longitude
here i have put origin as Delhi latitude and longitude & destination as chandigarh latitude longitude
https://maps.googleapis.com/maps/api/directions/json?origin=28.704060,77.102493&destination=30.733315,76.779419&sensor=false&key="PUT YOUR MAP API KEY"

This worked for me. With the method mentioned here I was able to draw polylines on Google Maps V2. I drew a new line whenever the user location got changed, so the the polyline looks like the path followed by user on map.
Source code at.
Github: prasang7/eTaxi-Meter
Please ignore other modules of this project related to distance calculation and User Interface if you are not interested in them.

Can we call MapView Inside an layout

one of the the blogger has given an wonderful idea of calling MapView class inside an application.
turn by turn directions in MapView
the code is
showDirections.setOnClickListener(new View.OnClickListener() {
public void onClick(final View view) {
final Intent intent = new Intent(Intent.ACTION_VIEW,
Uri.parse(
"http://maps.google.com/maps?" +
"saddr=43.0054446,-87.9678884" +
"&daddr=42.9257104,-88.0508355"));
intent.setClassName(
"com.google.android.apps.maps",
"com.google.android.maps.MapsActivity");
startActivity(intent);
}
});
Is it possible to attach this Mapview to a layout, so that it opens with in the layout of our application. As this method opens outside our layout and application. I am looking to fix this MapView to a layout.Any code examples.Looking forward to your reply.thanks

I am writing answer to my own question and got help from other StackOverflow users.
This is full source code to draw direction path from source latitude and longitude to destination latitude and longitude.
So anyone who is accessing his latitude and longitude through his gps can get the direction from his gps device to the destination coordinates.
StackOverflow had an answer and I have changed to latitude and longitude rather than source and destination places.
stack overflow link for route path between source and destination
Thanks to above answers we could make such a change and get path direction.
public class DrawMapActivity extends MapActivity {
MapView myMapView = null;
MapController myMC = null;
GeoPoint geoPoint = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myMapView = (MapView) findViewById(R.id.mapview);
geoPoint = null;
myMapView.setSatellite(false);
double fromLat = 12.303534;
double fromLong = 76.64611;
double toLat = 12.9715987;
double toLong = 77.5945627;
String sourceLat = Double.toString(fromLat);
String sourceLong = Double.toString(fromLong);
String destinationLat = Double.toString(toLat);
String destinationLong = Double.toString(toLong);
String pairs[] = getDirectionData(sourceLat,sourceLong, destinationLat, destinationLong );
String[] lngLat = pairs[0].split(",");
// STARTING POINT
GeoPoint startGP = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6), (int) (Double.parseDouble(lngLat[0]) * 1E6));
myMC = myMapView.getController();
geoPoint = startGP;
myMC.setCenter(geoPoint);
myMC.setZoom(10);
myMapView.getOverlays().add(new DirectionPathOverlay(startGP, startGP));
// NAVIGATE THE PATH
GeoPoint gp1;
GeoPoint gp2 = startGP;
for (int i = 1; i < pairs.length; i++) {
lngLat = pairs[i].split(",");
gp1 = gp2;
// watch out! For GeoPoint, first:latitude, second:longitude
gp2 = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6),(int) (Double.parseDouble(lngLat[0]) * 1E6));
myMapView.getOverlays().add(new DirectionPathOverlay(gp1, gp2));
Log.d("xxx", "pair:" + pairs[i]);
}
// END POINT
myMapView.getOverlays().add(new DirectionPathOverlay(gp2, gp2));
myMapView.getController().animateTo(startGP);
myMapView.setBuiltInZoomControls(true);
myMapView.displayZoomControls(true);
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private String[] getDirectionData(String sourceLat, String sourceLong, String destinationLat, String destinationLong) {
String urlString = "http://maps.google.com/maps?f=d&hl=en&" +"saddr="+sourceLat+","+sourceLong+"&daddr="+destinationLat+","+destinationLong + "&ie=UTF8&0&om=0&output=kml";
Log.d("URL", urlString);
Document doc = null;
HttpURLConnection urlConnection = null;
URL url = null;
String pathConent = "";
try {
url = new URL(urlString.toString());
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = db.parse(urlConnection.getInputStream());
} catch (Exception e) {
}
NodeList nl = doc.getElementsByTagName("LineString");
for (int s = 0; s < nl.getLength(); s++) {
Node rootNode = nl.item(s);
NodeList configItems = rootNode.getChildNodes();
for (int x = 0; x < configItems.getLength(); x++) {
Node lineStringNode = configItems.item(x);
NodeList path = lineStringNode.getChildNodes();
pathConent = path.item(0).getNodeValue();
}
}
String[] tempContent = pathConent.split(" ");
return tempContent;
}
}
//*****************************************************************************
class DirectionPathOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
public DirectionPathOverlay(GeoPoint gp1, GeoPoint gp2) {
this.gp1 = gp1;
this.gp2 = gp2;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
Projection projection = mapView.getProjection();
if (shadow == false) {
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
paint.setColor(Color.BLUE);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(2);
canvas.drawLine((float) point.x, (float) point.y, (float) point2.x,(float) point2.y, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
}
}
Hope it helps for other Stack Overflow users

How to find optimal route between two points on google map and then highlight it?

Suppose I have two geolocations(points) on google map,now I want to highlight an optimal route between these two points through different cities.How can I do this ? I have searched on internet and found Drawing a line/path on Google Maps but this explains drawing a straight line between two points.I need to find route connecting different cites and at least the places which come in between two points.not a straight line.Can anyone give me some goodd tutorial or some idea how to do that ?
Answer: If any other person is facing same problem please see the accepted answer.To implement optimal route refer to http://csie-tw.blogspot.com/2009/06/android-driving-direction-route-path.html This is an excellent tutorial with working codes.You can modify them according to your need.And one more thing,while testing please give only those coordinates for which paths are possible(mistake that I was doing).Rest is all fine.Go ahead with the codes.Thanks.

go through this codes. Modify the code as per ur requirement
//mapdirection.java
public class mapdirection extends MapActivity{
MapView mapview;
MapRouteOverlay mapoverlay;
Context _context;
List<Overlay> maplistoverlay;
Drawable drawable,drawable2;
MapOverlay mapoverlay2,mapoverlay3;
GeoPoint srcpoint,destpoint;
Overlay overlayitem;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
setContentView(R.layout.map_direction);
RegisterActivities.registerActivity(this);
mapview=(MapView)this.findViewById(R.id.mapview);
callMap();
}
private void callMap() {
srcpoint=new GeoPoint((int)(Data.src_lat_date*1E6),(int)(Data.src_long_data*1E6));
maplistoverlay=mapview.getOverlays();
drawable=this.getResources().getDrawable(R.drawable.green_a);
mapoverlay2=new MapOverlay(drawable);
OverlayItem overlayitem = new OverlayItem(srcpoint, "", "");
mapoverlay2.addOverlay(overlayitem);
maplistoverlay.add(mapoverlay2);
destpoint=new GeoPoint((int)(Data.dest_lat_data*1E6),(int)(Data.dest_long_data*1E6));
drawable2=this.getResources().getDrawable(R.drawable.green_b);
mapoverlay3=new MapOverlay(drawable2);
OverlayItem overlayitem3 = new OverlayItem(destpoint, "", "");
mapoverlay3.addOverlay(overlayitem3);
maplistoverlay.add(mapoverlay3);
double dest_lat = Data.dest_lat_data;
double dest_long = Data.dest_long_data;
GeoPoint srcGeoPoint = new GeoPoint((int) (Data.src_lat_date* 1E6),
(int) (Data.src_long_data * 1E6));
GeoPoint destGeoPoint = new GeoPoint((int) (dest_lat * 1E6),
(int) (dest_long * 1E6));
DrawPath(srcGeoPoint, destGeoPoint, Color.BLUE, mapview);
mapview.getController().animateTo(srcGeoPoint);
mapview.getController().setZoom(13);
//mapview.setStreetView(true);
mapview.setBuiltInZoomControls(true);
mapview.invalidate();
}
private void DrawPath(GeoPoint src, GeoPoint dest, int color,
MapView mMapView01) {
// connect to map web service
StringBuilder urlString = new StringBuilder();
urlString.append("http://maps.google.com/maps?f=d&hl=en");
urlString.append("&saddr=");//from
urlString.append( Double.toString((double)src.getLatitudeE6()/1.0E6 ));
urlString.append(",");
urlString.append( Double.toString((double)src.getLongitudeE6()/1.0E6 ));
urlString.append("&daddr=");//to
urlString.append( Double.toString((double)dest.getLatitudeE6()/1.0E6 ));
urlString.append(",");
urlString.append( Double.toString((double)dest.getLongitudeE6()/1.0E6 ));
urlString.append("&ie=UTF8&0&om=0&output=kml");
Log.d("xxx","URL="+urlString.toString());
//System.out.println(urlString);
// get the kml (XML) doc. And parse it to get the coordinates(direction route).
Document doc = null;
HttpURLConnection urlConnection= null;
URL url = null;
try
{
url = new URL(urlString.toString());
urlConnection=(HttpURLConnection)url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = db.parse(urlConnection.getInputStream());
if(doc.getElementsByTagName("GeometryCollection").getLength()>0)
{
//String path = doc.getElementsByTagName("GeometryCollection").item(0).getFirstChild().getFirstChild().getNodeName();
String path = doc.getElementsByTagName("GeometryCollection").item(0).getFirstChild().getFirstChild().getFirstChild().getNodeValue() ;
Log.d("xxx","path="+ path);
String [] pairs = path.split(" ");
String[] lngLat = pairs[0].split(","); // lngLat[0]=longitude lngLat[1]=latitude lngLat[2]=height
// src
GeoPoint startGP = new GeoPoint((int)(Double.parseDouble(lngLat[1])*1E6),(int)(Double.parseDouble(lngLat[0])*1E6));
//mMapView01.getOverlays().add(overlayitem);
GeoPoint gp1;
GeoPoint gp2 = startGP;
for(int i=1;i<pairs.length;i++) // the last one would be crash
{
lngLat = pairs[i].split(",");
gp1 = gp2;
// watch out! For GeoPoint, first:latitude, second:longitude
gp2 = new GeoPoint((int)(Double.parseDouble(lngLat[1])*1E6),(int)(Double.parseDouble(lngLat[0])*1E6));
mMapView01.getOverlays().add(new MapRouteOverlay(gp1,gp2,2,color));
Log.d("xxx","pair:" + pairs[i]);
}
//mMapView01.getOverlays().add(new MapRouteOverlay(dest,dest, 3)); // use the default color
}
}
catch (MalformedURLException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
catch (ParserConfigurationException e)
{
e.printStackTrace();
}
catch (SAXException e)
{
e.printStackTrace();
}
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
//MapRouteOverlay.java
public class MapRouteOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
private int mode=0;
private int defaultColor;
public MapRouteOverlay(GeoPoint gp1,GeoPoint gp2,int mode) // GeoPoint is a int. (6E)
{
this.gp1 = gp1;
this.gp2 = gp2;
this.mode = mode;
defaultColor = 999; // no defaultColor
}
public MapRouteOverlay(GeoPoint gp1,GeoPoint gp2,int mode, int defaultColor)
{
this.gp1 = gp1;
this.gp2 = gp2;
this.mode = mode;
this.defaultColor = defaultColor;
}
public int getMode()
{
return mode;
}
public boolean draw
(Canvas canvas, MapView mapView, boolean shadow, long when)
{
Projection projection = mapView.getProjection();
if (shadow == false)
{
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
if(mode==2)
{
if(defaultColor==999)
paint.setColor(Color.RED);
else
paint.setColor(defaultColor);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(5);
paint.setAlpha(120);
canvas.drawLine(point.x, point.y, point2.x,point2.y, paint);
}
}
return super.draw(canvas, mapView, shadow, when);
}
}

Yeah its right that am answering this question after long time. But I think this can help any other.
Put this code in onCreate or in your own method.
MapView mv = (MapView)findViewById(R.id.mvGoogle);
mv.setBuiltInZoomControls(true);
MapController mc = mv.getController();
//getDirections(lat1,lon2,lat2,lon2);
ArrayList<GeoPoint> all_geo_points = getDirections(10.154929, 76.390316, 10.015861, 76.341867);
if(all_geo_points.size()>0){
GeoPoint moveTo = all_geo_points.get(0);
mc.animateTo(moveTo);
mc.setZoom(12);
mv.getOverlays().add(new MyOverlay(all_geo_points));
}else {
Toast.makeText(getApplicationContext(), "Not able to show route !!", Toast.LENGTH_LONG).show();
}
Now make your own custom overlay class.
public class MyOverlay extends Overlay {
private ArrayList<GeoPoint> all_geo_points;
public MyOverlay(ArrayList<GeoPoint> allGeoPoints) {
super();
this.all_geo_points = allGeoPoints;
}
#Override
public boolean draw(Canvas canvas, MapView mv, boolean shadow, long when) {
super.draw(canvas, mv, shadow);
drawPath(mv, canvas);
return true;
}
public void drawPath(MapView mv, Canvas canvas) {
int xPrev = -1, yPrev = -1, xNow = -1, yNow = -1;
Paint paint = new Paint();
paint.setColor(Color.BLUE);
paint.setStyle(Paint.Style.FILL_AND_STROKE);
paint.setStrokeWidth(4);
paint.setAlpha(100);
if (all_geo_points != null) for (int i = 0; i < all_geo_points.size() - 4; i++) {
GeoPoint gp = all_geo_points.get(i);
Point point = new Point();
mv.getProjection().toPixels(gp, point);
xNow = point.x;
yNow = point.y;
if (xPrev != -1) {
canvas.drawLine(xPrev, yPrev, xNow, yNow, paint);
}
xPrev = xNow;
yPrev = yNow;
}
}
}
Now this method will give you all GeoPoints to draw route.I'll prefer to put this code in separate AsyncTask.
public static ArrayList<GeoPoint> getDirections(double lat1, double lon1, double lat2, double lon2) {
String url = "http://maps.googleapis.com/maps/api/directions/xml?origin=" + lat1 + "," + lon1 + "&destination=" + lat2 + "," + lon2
+ "&sensor=false&units=metric";
String tag[] = {"lat", "lng"};
ArrayList<GeoPoint> list_of_geopoints = new ArrayList<GeoPoint>();
HttpResponse response = null;
try {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
response = httpClient.execute(httpPost, localContext);
InputStream in = response.getEntity().getContent();
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(in);
if (doc != null) {
NodeList nl1, nl2;
nl1 = doc.getElementsByTagName(tag[0]);
nl2 = doc.getElementsByTagName(tag[1]);
if (nl1.getLength() > 0) {
list_of_geopoints = new ArrayList<GeoPoint>();
for (int i = 0; i < nl1.getLength(); i++) {
Node node1 = nl1.item(i);
Node node2 = nl2.item(i);
double lat = Double.parseDouble(node1.getTextContent());
double lng = Double.parseDouble(node2.getTextContent());
list_of_geopoints.add(new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6)));
}
} else {
// No points found
}
}
} catch (Exception e) {
e.printStackTrace();
}
return list_of_geopoints;
}

How can I draw a line between two points in Google map in Android?

I am new to Android. I want to draw a line from one location to another in my application. How can I draw a line between two points in Android? Please help me.

You should add an Overlay to the map and override it's onDraw() method. That way you can draw whatever you want on the map.

use this it works fine for me
mapView.setBuiltInZoomControls(true);
mapController = mapView.getController();
ArrayList allGeoPoints = getDirections(8.487495, 76.948623,toLat 10.015861, 76.341867toLon);
GeoPoint moveTo = new GeoPoint(startLattitude, startLongigude);
mapController.setCenter(moveTo);
//mc.animateTo(moveTo);
mapController.setZoom(12);
mapView.getOverlays().add(new MyOverlay(allGeoPoints));
public static ArrayList getDirections(double lat1, double lon1, double lat2, double lon2) {
String url = "http://maps.googleapis.com/maps/api/directions/xml?origin=" +lat1 + "," + lon1 + "&destination=" + lat2 + "," + lon2 + "&sensor=false&units=metric";
String tag[] = { "lat", "lng" };
ArrayList listOfGeopoints = new ArrayList();
HttpResponse response = null;
try {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
response = httpClient.execute(httpPost, localContext);
InputStream in = response.getEntity().getContent();
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(in);
Log.e("********************** ",new JsonOperations().convertStreamToString(in).toString());
if (doc != null) {
NodeList nl1, nl2;
nl1 = doc.getElementsByTagName(tag[0]);
nl2 = doc.getElementsByTagName(tag[1]);
if (nl1.getLength() > 0) {
listOfGeopoints = new ArrayList();
for (int i = 0; i < nl1.getLength(); i++) {
Node node1 = nl1.item(i);
Node node2 = nl2.item(i);
double lat = Double.parseDouble(node1.getTextContent());
double lng = Double.parseDouble(node2.getTextContent());
listOfGeopoints.add(new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6)));
}
} else {
// No points found
}
}
} catch (Exception e) {
e.printStackTrace();
}
return listOfGeopoints;
}
And myoverlay class
public class MyOverlay extends Overlay {
private ArrayList allGeoPoints;
public MyOverlay(ArrayList allGeoPoints) {
super();
this.allGeoPoints = allGeoPoints;
}
#Override
public boolean draw(Canvas canvas, MapView mv, boolean shadow, long when) {
super.draw(canvas, mv, shadow);
drawPath(mv, canvas);
return true;
}
public void drawPath(MapView mv, Canvas canvas) {
int xPrev = -1, yPrev = -1, xNow = -1, yNow = -1;
Paint paint = new Paint();
paint.setColor(Color.BLUE);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(4);
//paint.setAlpha(100);
if (allGeoPoints != null)
for (int i = 0; i < allGeoPoints.size() - 4; i++) {
GeoPoint gp = (GeoPoint) allGeoPoints.get(i);
Point point = new Point();
mv.getProjection().toPixels(gp, point);
xNow = point.x;
yNow = point.y;
if (xPrev != -1) {
canvas.drawLine(xPrev, yPrev, xNow, yNow, paint);
}
xPrev = xNow;
yPrev = yNow;
}
}
}

Drawing a line/path on Google Maps

I've been busy for a long time finding out how to draw a line between two (GPS) points on the map in HelloMapView but with no luck.
Could anyone please tell me how to do so.
Suppose I use the HelloMapView which extends MapView. Do I need to use overlays? If so do I have to override the onDraw() method of the overlay and draw a line here? I actually tried these things but with no result.
Thank you in advance!

Thank you for your help. At last I could draw a line on the map.
This is how I done it:
/** Called when the activity is first created. */
private List<Overlay> mapOverlays;
private Projection projection;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
linearLayout = (LinearLayout) findViewById(R.id.zoomview);
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
mapOverlays = mapView.getOverlays();
projection = mapView.getProjection();
mapOverlays.add(new MyOverlay());
}
#Override
protected boolean isRouteDisplayed() {
return false;
}
class MyOverlay extends Overlay{
public MyOverlay(){
}
public void draw(Canvas canvas, MapView mapv, boolean shadow){
super.draw(canvas, mapv, shadow);
Paint mPaint = new Paint();
mPaint.setDither(true);
mPaint.setColor(Color.RED);
mPaint.setStyle(Paint.Style.FILL_AND_STROKE);
mPaint.setStrokeJoin(Paint.Join.ROUND);
mPaint.setStrokeCap(Paint.Cap.ROUND);
mPaint.setStrokeWidth(2);
GeoPoint gP1 = new GeoPoint(19240000,-99120000);
GeoPoint gP2 = new GeoPoint(37423157, -122085008);
Point p1 = new Point();
Point p2 = new Point();
Path path = new Path();
Projection projection=mapv.getProjection();
projection.toPixels(gP1, p1);
projection.toPixels(gP2, p2);
path.moveTo(p2.x, p2.y);
path.lineTo(p1.x,p1.y);
canvas.drawPath(path, mPaint);
}

For those who really only want to draw a simple line - there is indeed also the short short version.
GoogleMap map;
// ... get a map.
// Add a thin red line from London to New York.
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(51.5, -0.1), new LatLng(40.7, -74.0))
.width(5)
.color(Color.RED));
from https://developers.google.com/maps/documentation/android/reference/com/google/android/gms/maps/model/Polyline

// This Activity will draw a line between two selected points on Map
public class MainActivity extends MapActivity {
MapView myMapView = null;
MapController myMC = null;
GeoPoint geoPoint = null;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myMapView = (MapView) findViewById(R.id.mapview);
geoPoint = null;
myMapView.setSatellite(false);
String pairs[] = getDirectionData("ahmedabad", "vadodara");
String[] lngLat = pairs[0].split(",");
// STARTING POINT
GeoPoint startGP = new GeoPoint(
(int) (Double.parseDouble(lngLat[1]) * 1E6), (int) (Double
.parseDouble(lngLat[0]) * 1E6));
myMC = myMapView.getController();
geoPoint = startGP;
myMC.setCenter(geoPoint);
myMC.setZoom(15);
myMapView.getOverlays().add(new DirectionPathOverlay(startGP, startGP));
// NAVIGATE THE PATH
GeoPoint gp1;
GeoPoint gp2 = startGP;
for (int i = 1; i < pairs.length; i++) {
lngLat = pairs[i].split(",");
gp1 = gp2;
// watch out! For GeoPoint, first:latitude, second:longitude
gp2 = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6),
(int) (Double.parseDouble(lngLat[0]) * 1E6));
myMapView.getOverlays().add(new DirectionPathOverlay(gp1, gp2));
Log.d("xxx", "pair:" + pairs[i]);
}
// END POINT
myMapView.getOverlays().add(new DirectionPathOverlay(gp2, gp2));
myMapView.getController().animateTo(startGP);
myMapView.setBuiltInZoomControls(true);
myMapView.displayZoomControls(true);
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private String[] getDirectionData(String srcPlace, String destPlace) {
String urlString = "http://maps.google.com/maps?f=d&hl=en&saddr="
+ srcPlace + "&daddr=" + destPlace
+ "&ie=UTF8&0&om=0&output=kml";
Log.d("URL", urlString);
Document doc = null;
HttpURLConnection urlConnection = null;
URL url = null;
String pathConent = "";
try {
url = new URL(urlString.toString());
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = db.parse(urlConnection.getInputStream());
} catch (Exception e) {
}
NodeList nl = doc.getElementsByTagName("LineString");
for (int s = 0; s < nl.getLength(); s++) {
Node rootNode = nl.item(s);
NodeList configItems = rootNode.getChildNodes();
for (int x = 0; x < configItems.getLength(); x++) {
Node lineStringNode = configItems.item(x);
NodeList path = lineStringNode.getChildNodes();
pathConent = path.item(0).getNodeValue();
}
}
String[] tempContent = pathConent.split(" ");
return tempContent;
}
}
//*****************************************************************************
DirectionPathOverlay
public class DirectionPathOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
public DirectionPathOverlay(GeoPoint gp1, GeoPoint gp2) {
this.gp1 = gp1;
this.gp2 = gp2;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
Projection projection = mapView.getProjection();
if (shadow == false) {
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
paint.setColor(Color.BLUE);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(2);
canvas.drawLine((float) point.x, (float) point.y, (float) point2.x,
(float) point2.y, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
}
}

This is full source code to draw direction path from source latitude and longitude to destination latitude and longitude. I have changed the above code to fit for latitude and longitude rather than source and destination.
So anyone who is accessing his latitude and longitude through his gps can get the direction from his gps device to the destination coordinates.
Thanks to above answers we could make such a change and get path direction.
public class DrawMapActivity extends MapActivity {
MapView myMapView = null;
MapController myMC = null;
GeoPoint geoPoint = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
myMapView = (MapView) findViewById(R.id.mapview);
geoPoint = null;
myMapView.setSatellite(false);
double fromLat = 12.303534;
double fromLong = 76.64611;
double toLat = 12.9715987;
double toLong = 77.5945627;
String sourceLat = Double.toString(fromLat);
String sourceLong = Double.toString(fromLong);
String destinationLat = Double.toString(toLat);
String destinationLong = Double.toString(toLong);
String pairs[] = getDirectionData(sourceLat,sourceLong, destinationLat, destinationLong );
String[] lngLat = pairs[0].split(",");
// STARTING POINT
GeoPoint startGP = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6), (int) (Double.parseDouble(lngLat[0]) * 1E6));
myMC = myMapView.getController();
geoPoint = startGP;
myMC.setCenter(geoPoint);
myMC.setZoom(10);
myMapView.getOverlays().add(new DirectionPathOverlay(startGP, startGP));
// NAVIGATE THE PATH
GeoPoint gp1;
GeoPoint gp2 = startGP;
for (int i = 1; i < pairs.length; i++) {
lngLat = pairs[i].split(",");
gp1 = gp2;
// watch out! For GeoPoint, first:latitude, second:longitude
gp2 = new GeoPoint((int) (Double.parseDouble(lngLat[1]) * 1E6),(int) (Double.parseDouble(lngLat[0]) * 1E6));
myMapView.getOverlays().add(new DirectionPathOverlay(gp1, gp2));
Log.d("xxx", "pair:" + pairs[i]);
}
// END POINT
myMapView.getOverlays().add(new DirectionPathOverlay(gp2, gp2));
myMapView.getController().animateTo(startGP);
myMapView.setBuiltInZoomControls(true);
myMapView.displayZoomControls(true);
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
private String[] getDirectionData(String sourceLat, String sourceLong, String destinationLat, String destinationLong) {
String urlString = "http://maps.google.com/maps?f=d&hl=en&" +"saddr="+sourceLat+","+sourceLong+"&daddr="+destinationLat+","+destinationLong + "&ie=UTF8&0&om=0&output=kml";
Log.d("URL", urlString);
Document doc = null;
HttpURLConnection urlConnection = null;
URL url = null;
String pathConent = "";
try {
url = new URL(urlString.toString());
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.setDoInput(true);
urlConnection.connect();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
doc = db.parse(urlConnection.getInputStream());
} catch (Exception e) {
}
NodeList nl = doc.getElementsByTagName("LineString");
for (int s = 0; s < nl.getLength(); s++) {
Node rootNode = nl.item(s);
NodeList configItems = rootNode.getChildNodes();
for (int x = 0; x < configItems.getLength(); x++) {
Node lineStringNode = configItems.item(x);
NodeList path = lineStringNode.getChildNodes();
pathConent = path.item(0).getNodeValue();
}
}
String[] tempContent = pathConent.split(" ");
return tempContent;
}
}
//*****************************************************************************
class DirectionPathOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;
public DirectionPathOverlay(GeoPoint gp1, GeoPoint gp2) {
this.gp1 = gp1;
this.gp2 = gp2;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
Projection projection = mapView.getProjection();
if (shadow == false) {
Paint paint = new Paint();
paint.setAntiAlias(true);
Point point = new Point();
projection.toPixels(gp1, point);
paint.setColor(Color.BLUE);
Point point2 = new Point();
projection.toPixels(gp2, point2);
paint.setStrokeWidth(2);
canvas.drawLine((float) point.x, (float) point.y, (float) point2.x,(float) point2.y, paint);
}
return super.draw(canvas, mapView, shadow, when);
}
#Override
public void draw(Canvas canvas, MapView mapView, boolean shadow) {
// TODO Auto-generated method stub
super.draw(canvas, mapView, shadow);
}
}
Hope it helps for other Stack Overflow users

This can be done by using intents too:
final Intent intent = new Intent(Intent.ACTION_VIEW,
Uri.parse(
"http://maps.google.com/maps?" +
"saddr="+YOUR_START_LONGITUDE+","+YOUR_START_LATITUDE+"&daddr="YOUR_END_LONGITUDE+","+YOUR_END_LATITUDE));
intent.setClassName(
"com.google.android.apps.maps",
"com.google.android.maps.MapsActivity");
startActivity(intent);

It is really easy with Google Maps Android API v2
Just copy the example from Developer documentation
(of course you have to init your map first)
GoogleMap map;
// ... get a map.
// Add a thin red line from London to New York.
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(51.5, -0.1), new LatLng(40.7, -74.0))
.width(5)
.color(Color.RED));

Yes you need to use overlays.
You need to get the MapView's overlays and add your new overlay onto it.
Your class extends Overlay, which is a transparent canvas in which you can draw on it like any other canvas.
You can use mapView.getProjection() to get projection of map view.
...
More info found here: http://blogoscoped.com/archive/2008-12-15-n14.html

You can get the projection from the MapView object which is passed into the draw() method:
mapv.getProjection().toPixels(gP1, p1);

public class MainActivity extends FragmentActivity {
List<Overlay> mapOverlays;
GeoPoint point1, point2;
LocationManager locManager;
Drawable drawable;
Document document;
GMapV2GetRouteDirection v2GetRouteDirection;
LatLng fromPosition;
LatLng toPosition;
GoogleMap mGoogleMap;
MarkerOptions markerOptions;
Location location ;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
v2GetRouteDirection = new GMapV2GetRouteDirection();
SupportMapFragment supportMapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mGoogleMap = supportMapFragment.getMap();
// Enabling MyLocation in Google Map
mGoogleMap.setMyLocationEnabled(true);
mGoogleMap.getUiSettings().setZoomControlsEnabled(true);
mGoogleMap.getUiSettings().setCompassEnabled(true);
mGoogleMap.getUiSettings().setMyLocationButtonEnabled(true);
mGoogleMap.getUiSettings().setAllGesturesEnabled(true);
mGoogleMap.setTrafficEnabled(true);
mGoogleMap.animateCamera(CameraUpdateFactory.zoomTo(12));
markerOptions = new MarkerOptions();
fromPosition = new LatLng(11.663837, 78.147297);
toPosition = new LatLng(11.723512, 78.466287);
GetRouteTask getRoute = new GetRouteTask();
getRoute.execute();
}
/**
*
* #author VIJAYAKUMAR M
* This class Get Route on the map
*
*/
private class GetRouteTask extends AsyncTask<String, Void, String> {
private ProgressDialog Dialog;
String response = "";
#Override
protected void onPreExecute() {
Dialog = new ProgressDialog(MainActivity.this);
Dialog.setMessage("Loading route...");
Dialog.show();
}
#Override
protected String doInBackground(String... urls) {
//Get All Route values
document = v2GetRouteDirection.getDocument(fromPosition, toPosition, GMapV2GetRouteDirection.MODE_DRIVING);
response = "Success";
return response;
}
#Override
protected void onPostExecute(String result) {
mGoogleMap.clear();
if(response.equalsIgnoreCase("Success")){
ArrayList<LatLng> directionPoint = v2GetRouteDirection.getDirection(document);
PolylineOptions rectLine = new PolylineOptions().width(10).color(
Color.RED);
for (int i = 0; i < directionPoint.size(); i++) {
rectLine.add(directionPoint.get(i));
}
// Adding route on the map
mGoogleMap.addPolyline(rectLine);
markerOptions.position(toPosition);
markerOptions.draggable(true);
mGoogleMap.addMarker(markerOptions);
}
Dialog.dismiss();
}
}
#Override
protected void onStop() {
super.onStop();
finish();
}
}
Route Helper class
public class GMapV2GetRouteDirection {
public final static String MODE_DRIVING = "driving";
public final static String MODE_WALKING = "walking";
public GMapV2GetRouteDirection() { }
public Document getDocument(LatLng start, LatLng end, String mode) {
String url = "http://maps.googleapis.com/maps/api/directions/xml?"
+ "origin=" + start.latitude + "," + start.longitude
+ "&destination=" + end.latitude + "," + end.longitude
+ "&sensor=false&units=metric&mode=driving";
try {
HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpPost httpPost = new HttpPost(url);
HttpResponse response = httpClient.execute(httpPost, localContext);
InputStream in = response.getEntity().getContent();
DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
Document doc = builder.parse(in);
return doc;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
public String getDurationText (Document doc) {
NodeList nl1 = doc.getElementsByTagName("duration");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "text"));
Log.i("DurationText", node2.getTextContent());
return node2.getTextContent();
}
public int getDurationValue (Document doc) {
NodeList nl1 = doc.getElementsByTagName("duration");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "value"));
Log.i("DurationValue", node2.getTextContent());
return Integer.parseInt(node2.getTextContent());
}
public String getDistanceText (Document doc) {
NodeList nl1 = doc.getElementsByTagName("distance");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "text"));
Log.i("DistanceText", node2.getTextContent());
return node2.getTextContent();
}
public int getDistanceValue (Document doc) {
NodeList nl1 = doc.getElementsByTagName("distance");
Node node1 = nl1.item(0);
NodeList nl2 = node1.getChildNodes();
Node node2 = nl2.item(getNodeIndex(nl2, "value"));
Log.i("DistanceValue", node2.getTextContent());
return Integer.parseInt(node2.getTextContent());
}
public String getStartAddress (Document doc) {
NodeList nl1 = doc.getElementsByTagName("start_address");
Node node1 = nl1.item(0);
Log.i("StartAddress", node1.getTextContent());
return node1.getTextContent();
}
public String getEndAddress (Document doc) {
NodeList nl1 = doc.getElementsByTagName("end_address");
Node node1 = nl1.item(0);
Log.i("StartAddress", node1.getTextContent());
return node1.getTextContent();
}
public String getCopyRights (Document doc) {
NodeList nl1 = doc.getElementsByTagName("copyrights");
Node node1 = nl1.item(0);
Log.i("CopyRights", node1.getTextContent());
return node1.getTextContent();
}
public ArrayList<LatLng> getDirection (Document doc) {
NodeList nl1, nl2, nl3;
ArrayList<LatLng> listGeopoints = new ArrayList<LatLng>();
nl1 = doc.getElementsByTagName("step");
if (nl1.getLength() > 0) {
for (int i = 0; i < nl1.getLength(); i++) {
Node node1 = nl1.item(i);
nl2 = node1.getChildNodes();
Node locationNode = nl2.item(getNodeIndex(nl2, "start_location"));
nl3 = locationNode.getChildNodes();
Node latNode = nl3.item(getNodeIndex(nl3, "lat"));
double lat = Double.parseDouble(latNode.getTextContent());
Node lngNode = nl3.item(getNodeIndex(nl3, "lng"));
double lng = Double.parseDouble(lngNode.getTextContent());
listGeopoints.add(new LatLng(lat, lng));
locationNode = nl2.item(getNodeIndex(nl2, "polyline"));
nl3 = locationNode.getChildNodes();
latNode = nl3.item(getNodeIndex(nl3, "points"));
ArrayList<LatLng> arr = decodePoly(latNode.getTextContent());
for(int j = 0 ; j < arr.size() ; j++) {
listGeopoints.add(new LatLng(arr.get(j).latitude, arr.get(j).longitude));
}
locationNode = nl2.item(getNodeIndex(nl2, "end_location"));
nl3 = locationNode.getChildNodes();
latNode = nl3.item(getNodeIndex(nl3, "lat"));
lat = Double.parseDouble(latNode.getTextContent());
lngNode = nl3.item(getNodeIndex(nl3, "lng"));
lng = Double.parseDouble(lngNode.getTextContent());
listGeopoints.add(new LatLng(lat, lng));
}
}
return listGeopoints;
}
private int getNodeIndex(NodeList nl, String nodename) {
for(int i = 0 ; i < nl.getLength() ; i++) {
if(nl.item(i).getNodeName().equals(nodename))
return i;
}
return -1;
}
private ArrayList<LatLng> decodePoly(String encoded) {
ArrayList<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 position = new LatLng((double) lat / 1E5, (double) lng / 1E5);
poly.add(position);
}
return poly;
}
}

just i will find draw with some rectangle in mapview just we want change paint as we like
EmptyOverlay.java
public class EmptyOverlay extends Overlay {
private float x1,y1;
private MapExampleActivity mv = null;
private Overlay overlay = null;
public EmptyOverlay(MapExampleActivity mapV){
mv = mapV;
}
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
// TODO Auto-generated method stub
return super.draw(canvas, mapView, shadow, when);
}
#Override
public boolean onTouchEvent(MotionEvent e, MapView mapView) {
if(mv.isEditMode()){
if(e.getAction() == MotionEvent.ACTION_DOWN){
//when user presses the map add a new overlay to the map
//move events will be catched by newly created overlay
x1 = y1 = 0;
x1 = e.getX();
y1 = e.getY();
overlay = new MapOverlay(mv, x1, y1);
mapView.getOverlays().add(overlay);
}
if(e.getAction() == MotionEvent.ACTION_MOVE){
}
//---when user lifts his finger---
if (e.getAction() == MotionEvent.ACTION_UP) {
}
return true;
}
return false;
}
}
MapExampleActivity.java
public class MapExampleActivity extends MapActivity {
private MapView mapView;
private boolean isEditMode = false;
private Button toogle;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
toogle = (Button)findViewById(R.id.toogleMap);
toogle.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
toogleEditMode();
}
});
mapView = (MapView)findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true); //display zoom controls
//add one empty overlay acting as a overlay loader. This will catch press events and will add the actual overlays
mapView.getOverlays().add(new EmptyOverlay(this));
mapView.postInvalidate();
}
//toogle edit mode for drawing or navigating the map
private void toogleEditMode(){
isEditMode = !isEditMode;
}
#Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
#Override
protected boolean isLocationDisplayed() {
return false;
}
public boolean isEditMode(){
return this.isEditMode;
}
public MapView getMapView(){
return this.mapView;
}
}
MapOverlay.java
public class MapOverlay extends Overlay {
private float x1,y1,x2,y2;
private GeoPoint p1=null,p2=null;
private MapExampleActivity mv = null;
private Paint paint = new Paint();
private boolean isUp = false;
//constructor receiving the initial point
public MapOverlay(MapExampleActivity mapV,float x,float y){
paint.setStrokeWidth(2.0f);
x1 = x;
y1 = y;
mv = mapV;
p1 = mapV.getMapView().getProjection().fromPixels((int)x1,(int)y1);
}
//override draw method to add our custom drawings
#Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow,
long when) {
if(p1 != null && p2 != null){
//get the 2 geopoints defining the area and transform them to pixels
//this way if we move or zoom the map rectangle will follow accordingly
Point screenPts1 = new Point();
mapView.getProjection().toPixels(p1, screenPts1);
Point screenPts2 = new Point();
mapView.getProjection().toPixels(p2, screenPts2);
//draw inner rectangle
paint.setColor(0x4435EF56);
paint.setStyle(Style.FILL);
canvas.drawRect(screenPts1.x, screenPts1.y, screenPts2.x, screenPts2.y, paint);
//draw outline rectangle
paint.setColor(0x88158923);
paint.setStyle(Style.STROKE);
canvas.drawRect(screenPts1.x, screenPts1.y, screenPts2.x, screenPts2.y, paint);
}
return true;
}
#Override
public boolean onTouchEvent(MotionEvent e, MapView mapView) {
if(mv.isEditMode() && !isUp){
if(e.getAction() == MotionEvent.ACTION_DOWN){
x1 = y1 = 0;
x1 = e.getX();
y1 = e.getY();
p1 = mapView.getProjection().fromPixels((int)x1,(int)y1);
}
//here we constantly change geopoint p2 as we move out finger
if(e.getAction() == MotionEvent.ACTION_MOVE){
x2 = e.getX();
y2 = e.getY();
p2 = mapView.getProjection().fromPixels((int)x2,(int)y2);
}
//---when user lifts his finger---
if (e.getAction() == MotionEvent.ACTION_UP) {
isUp = true;
}
return true;
}
return false;
}
}
see this http://n3vrax.wordpress.com/2011/08/13/drawing-overlays-on-android-map-view/

Try this one:
Add itemizedOverlay class:
public class AndroidGoogleMapsActivity extends MapActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Displaying Zooming controls
MapView mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
MapController mc = mapView.getController();
double lat = Double.parseDouble("48.85827758964043");
double lon = Double.parseDouble("2.294543981552124");
GeoPoint geoPoint = new GeoPoint((int)(lat * 1E6), (int)(lon * 1E6));
mc.animateTo(geoPoint);
mc.setZoom(15);
mapView.invalidate();
/**
* Placing Marker
* */
List<Overlay> mapOverlays = mapView.getOverlays();
Drawable drawable = this.getResources().getDrawable(R.drawable.mark_red);
AddItemizedOverlay itemizedOverlay =
new AddItemizedOverlay(drawable, this);
OverlayItem overlayitem = new OverlayItem(geoPoint, "Hello", "Sample Overlay item");
itemizedOverlay.addOverlay(overlayitem);
mapOverlays.add(itemizedOverlay);
}
#Override
protected boolean isRouteDisplayed() {
return false;
}
}

Simply get route form this url and do next ...
Origin ---> starting point latitude & longitude
Destination---> ending point latitude & longitude
here i have put origin as Delhi latitude and longitude & destination as chandigarh latitude longitude
https://maps.googleapis.com/maps/api/directions/json?origin=28.704060,77.102493&destination=30.733315,76.779419&sensor=false&key="PUT YOUR MAP API KEY"

This worked for me. With the method mentioned here I was able to draw polylines on Google Maps V2. I drew a new line whenever the user location got changed, so the the polyline looks like the path followed by user on map.
Source code at.
Github: prasang7/eTaxi-Meter
Please ignore other modules of this project related to distance calculation and User Interface if you are not interested in them.