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Force Close Error: I am drawing a route between two points in a map

when its running, after touch 2 points as markers to drawing route, then the application force close.
DirectionsJSONParser.java
import com.google.android.gms.maps.model.LatLng;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
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<>() ;
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 : 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;
}
}
this is the MapsActivity.java, the logcat said that there is error in this. in part private class ParserTask extends AsyncTask(String, Integer, List(List(HashMap(String,String)))){}
import androidx.fragment.app.FragmentActivity;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.widget.Toast;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
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.MarkerOptions;
import com.google.android.gms.maps.model.Polyline;
import com.google.android.gms.maps.model.PolylineOptions;
import org.json.JSONObject;
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;
public class MapsActivity extends FragmentActivity implements OnMapReadyCallback{
private GoogleMap mMap;
private LatLng mOrigin;
private LatLng mDestination;
private Polyline mPolyline;
ArrayList<LatLng> mMarkerPoints;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
// 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);
mMarkerPoints = new ArrayList<>();
}
#Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
#Override
public void onMapClick(LatLng point) {
// Already two locations
if(mMarkerPoints.size()>1){
mMarkerPoints.clear();
mMap.clear();
}
// Adding new item to the ArrayList
mMarkerPoints.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(mMarkerPoints.size()==1){
options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN));
}else if(mMarkerPoints.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(mMarkerPoints.size() >= 2){
mOrigin = mMarkerPoints.get(0);
mDestination = mMarkerPoints.get(1);
drawRoute();
}
}
});
}
private void drawRoute(){
// Getting URL to the Google Directions API
String url = getDirectionsUrl(mOrigin, mDestination);
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;
// Key
String key = "key=" + getString(R.string.google_maps_key);
// Building the parameters to the web service
String parameters = str_origin+"&"+str_dest+"&"+key;
// 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 on download", e.toString());
}finally{
iStream.close();
urlConnection.disconnect();
}
return data;
}
/** A class to download data from Google Directions URL */
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]);
Log.d("DownloadTask","DownloadTask : " + data);
}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 Directions 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;
// Traversing through all the routes
for(int i=0;i<result.size();i++){
points = new ArrayList<LatLng>();
lineOptions = new PolylineOptions();
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
// Fetching all the points in i-th route
for(int j=0;j<path.size();j++){
HashMap<String,String> point = path.get(j);
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
// Adding all the points in the route to LineOptions
lineOptions.addAll(points);
lineOptions.width(8);
lineOptions.color(Color.RED);
}
// Drawing polyline in the Google Map for the i-th route
if(lineOptions != null) {
if(mPolyline != null){
mPolyline.remove();
}
mPolyline = mMap.addPolyline(lineOptions);
}else
Toast.makeText(getApplicationContext(),"No route is found", Toast.LENGTH_LONG).show();
}
}
}
The Error
08-20 08:47:03.252 26887-26887/com.aplikasi.ica.mydirections E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.aplikasi.ica.mydirections, PID: 26887
java.lang.NullPointerException
at com.aplikasi.ica.mydirections.MapsActivity$ParserTask.onPostExecute(MapsActivity.java:238)
at com.aplikasi.ica.mydirections.MapsActivity$ParserTask.onPostExecute(MapsActivity.java:210)
at android.os.AsyncTask.finish(AsyncTask.java:632)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:149)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
at dalvik.system.NativeStart.main(Native Method)
is the problem in manifest? could you please solve my problem???

error: Attempt to invoke interface method 'int java.util.List.size()' [duplicate]

This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 5 years ago.
i try to build an app that show a route and draw it, for after calculate distance an travel time, for all points A + B + C + D... but it show this error, i don't know how fix.
i looking for similar answers, but no response for this case
TAL EXCEPTION: main
Process: com.elgeos.wayp.wa, PID: 17963
java.lang.NullPointerException: Attempt to invoke interface method 'int java.util.List.size()' on a null object reference
at com.elgeos.wayp.wa.PathGoogleMapActivity$ParserTask.onPostExecute(PathGoogleMapActivity.java:139)
at com.elgeos.wayp.wa.PathGoogleMapActivity$ParserTask.onPostExecute(PathGoogleMapActivity.java:113)
at android.os.AsyncTask.finish(AsyncTask.java:651)
at android.os.AsyncTask.-wrap1(AsyncTask.java)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:668)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Below i attach my full java activity, Android Studio show me all ok, but when i debug app, fail app
package com.elgeos.wayp.wa;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.json.JSONObject;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
public class PathGoogleMapActivity extends FragmentActivity implements OnMapReadyCallback {
private static final LatLng LOWER_MANHATTAN = new LatLng(40.722543,
-73.998585);
private static final LatLng BROOKLYN_BRIDGE = new LatLng(40.7057, -73.9964);
private static final LatLng WALL_STREET = new LatLng(40.7064, -74.0094);
GoogleMap mMap;
final String TAG = "PathGoogleMapActivity";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_path_google_map);
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
}
#Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
MarkerOptions options = new MarkerOptions();
options.position(LOWER_MANHATTAN);
options.position(BROOKLYN_BRIDGE);
options.position(WALL_STREET);
mMap.addMarker(options);
String url = getMapsApiDirectionsUrl();
ReadTask downloadTask = new ReadTask();
downloadTask.execute(url);
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(BROOKLYN_BRIDGE,
13));
addMarkers();
}
private String getMapsApiDirectionsUrl() {
String waypoints = "waypoints=optimize:true|"
+ LOWER_MANHATTAN.latitude + "," + LOWER_MANHATTAN.longitude
+ "|" + "|" + BROOKLYN_BRIDGE.latitude + ","
+ BROOKLYN_BRIDGE.longitude + "|" + WALL_STREET.latitude + ","
+ WALL_STREET.longitude;
String sensor = "sensor=false";
String params = waypoints + "&" + sensor;
String output = "json";
String url = "https://maps.googleapis.com/maps/api/directions/"
+ output + "?" + params;
return url;
}
private void addMarkers() {
if (mMap != null) {
mMap.addMarker(new MarkerOptions().position(BROOKLYN_BRIDGE)
.title("First Point"));
mMap.addMarker(new MarkerOptions().position(LOWER_MANHATTAN)
.title("Second Point"));
mMap.addMarker(new MarkerOptions().position(WALL_STREET)
.title("Third Point"));
}
}
private class ReadTask extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... url) {
String data = "";
try {
HttpConnection http = new HttpConnection();
data = http.readUrl(url[0]);
} catch (Exception e) {
Log.d("Background Task", e.toString());
}
return data;
}
#Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
new ParserTask().execute(result);
}
}
private class ParserTask extends
AsyncTask<String, Integer, List<List<HashMap<String, String>>>> {
#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]);
PathJSONParser parser = new PathJSONParser();
routes = parser.parse(jObject);
} catch (Exception e) {
e.printStackTrace();
}
return routes;
}
#Override
protected void onPostExecute(List<List<HashMap<String, String>>> routes) {
ArrayList<LatLng> points = null;
PolylineOptions polyLineOptions = null;
// traversing through routes
for (int i = 0; i < routes.size(); i++) {
points = new ArrayList<LatLng>();
polyLineOptions = new PolylineOptions();
List<HashMap<String, String>> path = routes.get(i);
for (int j = 0; j < path.size(); j++) {
HashMap<String, String> point = path.get(j);
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
polyLineOptions.addAll(points);
polyLineOptions.width(2);
polyLineOptions.color(Color.BLUE);
}
mMap.addPolyline(polyLineOptions);
}
}
}

List> path = routes.get(i);
Here, the routes is null and you try to get size of the path list which is null.
So you get a NullPointerException.

onMarkerClick listener drawing route and calculate distance

On my map i want to make user when click on marker it be source and on click on another marker it be destination and drawing route calculating the distance
my code didn't do that
I don't know what's wrong.
package com.example.gmapsapp;
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.Dialog;
import android.graphics.Color;
import android.location.Address;
import android.location.Geocoder;
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.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import com.google.android.gms.common.ConnectionResult;
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.GoogleMap.OnMarkerClickListener;
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.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
public class Publicplaces extends FragmentActivity {
private static final int GPS_ERRORDIALOG_REQUEST = 9001;
public Marker marker;
private static final double NASRCITY_LAT = 30.066108,
NASRCITY_LNG =31.336184;
private static final float DEFAULTZOOM = 13;
GoogleMap map;
ArrayList<LatLng> markerPoints;
TextView tvDistanceDuration;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (servicesOK()) {
setContentView(R.layout.publicplaces);
if (initMap()) {
gotoLocation(NASRCITY_LAT, NASRCITY_LNG, DEFAULTZOOM);
tvDistanceDuration = (TextView) findViewById(R.id.tv_distance_time);
}
else {
Toast.makeText(this, "Map not available!", Toast.LENGTH_SHORT).show();
}
}
else {
setContentView(R.layout.activity_main);
}
// 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);
map.setOnMarkerClickListener(new OnMarkerClickListener() {
public void onMarkerClick(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);
//int s = markerPoints.size();
/**
* 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));
}
else{
options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_YELLOW));
}
// 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);
//LatLng next = markerPoints.get(2);
// 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);
}
}
#Override
public boolean onMarkerClick(Marker arg0) {
// TODO Auto-generated method stub
return false;
};
});
}
private boolean servicesOK() {
int isAvailable = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (isAvailable == ConnectionResult.SUCCESS) {
return true;
}
else if (GooglePlayServicesUtil.isUserRecoverableError(isAvailable)) {
Dialog dialog = GooglePlayServicesUtil.getErrorDialog(isAvailable, this, GPS_ERRORDIALOG_REQUEST);
dialog.show();
}
else {
Toast.makeText(this, "Can't connect to Google Play services", Toast.LENGTH_SHORT).show();
}
return false;
}
private boolean initMap() {
if (map == null) {
SupportMapFragment mapFrag =
(SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
map = mapFrag.getMap();
}
if (map != null){
setupmap();
}
return (map != null);
}
private void setupmap() {
map.addMarker(new MarkerOptions().position(new LatLng(30.060953, 31.357416)).title("Ahmed Hendy Pharmacy")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.056645, 31.354756)).title("Hasan Ali Pharmacy")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.051739, 31.355807)).title("Osama El-Meleegi's Pharmacy")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.054673, 31.346751)).title("Ezaby Pharmacies")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.054711, 31.35052)).title("pharmacies drug")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.045609, 31.361686)).title("Maraghy tenth district")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.040400, 31.329994)).title("Anji Pharmacy")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.064593, 31.339916)).title("Amr Pharmacy")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.056538, 31.338285)).title("Pharmacies Delmar and Atallah")).showInfoWindow();
map.addMarker(new MarkerOptions().position(new LatLng(30.061886, 31.333264)).title("J. Bakl Pharmacy")).showInfoWindow();
}
private void gotoLocation(double lat, double lng,float zoom) {
LatLng ll = new LatLng(lat, lng);
CameraUpdate update = CameraUpdateFactory.newLatLngZoom(ll, zoom);
map.moveCamera(update);
}
public void geoLocate(View v) throws IOException {
hideSoftKeyboard(v);
EditText et = (EditText) findViewById(R.id.editText1);
String location = et.getText().toString();
Geocoder gc = new Geocoder(this);
List<Address> list = gc.getFromLocationName(location, 1);
Address add = list.get(0);
String locality = add.getLocality();
Toast.makeText(this, locality, Toast.LENGTH_LONG).show();
double lat = add.getLatitude();
double lng = add.getLongitude();
gotoLocation(lat, lng, DEFAULTZOOM);
}
private void hideSoftKeyboard(View v) {
// TODO Auto-generated method stub
}
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;
//String str_next = "next="+next.latitude+","+next.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;
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(3);
lineOptions.color(Color.RED);
}
tvDistanceDuration.setText("Distance:"+distance + ", Duration:"+duration);
// Drawing polyline in the Google Map for the i-th route
map.addPolyline(lineOptions);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
and this is json
package com.example.gmapsapp;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.google.android.gms.maps.model.LatLng;
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;
JSONObject jDistance = null;
JSONObject jDuration = 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<HashMap<String, String>> path = new ArrayList<HashMap<String, String>>();
/** Traversing all legs */
for(int j=0;j<jLegs.length();j++){
/** Getting distance from the json data */
jDistance = ((JSONObject) jLegs.get(j)).getJSONObject("distance");
HashMap<String, String> hmDistance = new HashMap<String, String>();
hmDistance.put("distance", jDistance.getString("text"));
/** Getting duration from the json data */
jDuration = ((JSONObject) jLegs.get(j)).getJSONObject("duration");
HashMap<String, String> hmDuration = new HashMap<String, String>();
hmDuration.put("duration", jDuration.getString("text"));
/** Adding distance object to the path */
path.add(hmDistance);
/** Adding duration object to the path */
path.add(hmDuration);
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 : 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;
}
}

Why do you have 2 async task in one class? Its not a good technique to be followed, you can perform the download and parsing in the same async task thread. Those two threads may conflict and you have not written any syncronization code. Please add and see if that works.
Please have a look at this tutorial for code implementation.
Hope that Helps!!

Android app to compare a set of coordinates to current location and provide a list of nearby places

pls i have been trying to develop an app that can compare a give list of places with their coordinates to a user's current location and displays a list of nearby places from the given list, i was able to get my app to get current location and show a route to a given coordinate but i don't know where to go from here as regard to getting a list of nearby places from coordinates which i will provide. below are my java and xml code. thank you
Java file
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.graphics.Color;
import android.location.Criteria;
import android.location.Location;
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 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.MarkerOptions;
import com.google.android.gms.maps.model.PolylineOptions;
public class MyLefkosa extends FragmentActivity {
GoogleMap map;
ArrayList<LatLng> markerPoints;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mygirne);
// 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();
if(map!=null){
// Enable MyLocation Button in the Map
map.setMyLocationEnabled(true);
// change map type to hybrid
map.setMapType(GoogleMap.MAP_TYPE_NORMAL);
// set traffic
map.setTrafficEnabled(true);
// get user location
// Setting onclick event listener for the map
LocationManager manager=(LocationManager) getSystemService(LOCATION_SERVICE);
Criteria criteria=new Criteria();
String provider =manager.getBestProvider(criteria, true);
Location cloc=manager.getLastKnownLocation(provider);
double lat=35.177;
double lng =33.3456;
lat =cloc.getLatitude();
lng= cloc.getLongitude();
LatLng latlng = new LatLng (lat,lng);
map.moveCamera(CameraUpdateFactory.newLatLng(latlng));
map.animateCamera(CameraUpdateFactory.zoomTo(15));
map.addMarker(new MarkerOptions()
.title("Your Current Location")
.position(latlng));
LatLng LEFKOSA =
new LatLng(35.166666700000000000,33.366666699999996000);
map.addMarker(new MarkerOptions()
.position(LEFKOSA)
.title("LEFKOSA")
.snippet("LEFKOSA CITY CENTRE")
.icon(BitmapDescriptorFactory.defaultMarker(
BitmapDescriptorFactory.HUE_AZURE)));
// Getting URL to the Google Directions API
String url = getDirectionsUrl(latlng, LEFKOSA);
DownloadTask downloadTask = new DownloadTask();
// Start downloading json data from Google Directions API
downloadTask.execute(url);
}
}
private String getDirectionsUrl(LatLng latlng,LatLng LEFKOSA){
// Origin of route
String str_origin = "origin="+latlng.latitude+","+latlng.longitude;
// Destination of route
String str_dest = "destination="+LEFKOSA.latitude+","+LEFKOSA.longitude;
// Sensor enabled
String sensor = "sensor=true";
// 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]);
Directions parser = new Directions();
// 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();
// Traversing through all the routes
for(int i=0;i<result.size();i++){
points = new ArrayList<LatLng>();
lineOptions = new PolylineOptions();
// Fetching i-th route
List<HashMap<String, String>> path = result.get(i);
// Fetching all the points in i-th route
for(int j=0;j<path.size();j++){
HashMap<String,String> point = path.get(j);
double lat = Double.parseDouble(point.get("lat"));
double lng = Double.parseDouble(point.get("lng"));
LatLng position = new LatLng(lat, lng);
points.add(position);
}
// Adding all the points in the route to LineOptions
lineOptions.addAll(points);
lineOptions.width(5);
lineOptions.color(Color.CYAN);
}
// Drawing polyline in the Google Map for the i-th route
map.addPolyline(lineOptions);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.mygirne, menu);
return true;
}
}
xml file
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.firsttry.cyptour.MyLefkosa" >
<fragment
android:id="#+id/map"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
class="com.google.android.gms.maps.SupportMapFragment" />
</RelativeLayout>

try the distnaceBetween() method for location: http://developer.android.com/reference/android/location/Location.html

Cannot be resolved to a type

I was wondering if anyone can help me with this. I am trying to add auto-completion to my app with the Google Places API. I am following a tutorial and the following code is what I am having a problem with:
URL googlePlaces = new URL(
"https://maps.googleapis.com/maps/api/place/autocomplete/json?input=" +
URLEncoder.encode(args[0], "UTF-8") +
"&types=geocode&language=en&sensor=true&key=" +
getResources().getString(R.string.googleAPIKey));
URLConnection tc = googlePlaces.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
tc.getInputStream()));
The line "getResources()" is coming back with a "cannot resolve to a type" error because of the "R.string.googleAPIKey". I will put in my whole code down below:
package com.multinav;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLEncoder;
import java.util.ArrayList;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.AutoCompleteTextView;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
public class MainActivity extends FragmentActivity {
private GoogleMap googleMap;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.item_list);
setUpMapIfNeeded();
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the map.
if (googleMap == null){
// Try to obtain the map from the SupportMapFragment.
googleMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMap();
// Check if we were successful in obtaining the map.
if (googleMap != null){
setUpMap();
}
}
}
private void setUpMap() {
// Enable MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
// Get LocationManager object from System Service LOCATION_SERVICE
LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
// Create a criteria object to retrieve provider
Criteria criteria = new Criteria();
// Get the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
// Get Current Location
Location myLocation = locationManager.getLastKnownLocation(provider);
// Set map type
googleMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
// Get latitude of the current location
double latitude = myLocation.getLatitude();
// get longitude of the current location
double longitude = myLocation.getLongitude();
// Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
// Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(20));
googleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("BAAMMMM!"));
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public class Main extends Activity {
/** Called when the activity is first created. */
public ArrayAdapter<String> adapter;
public AutoCompleteTextView textview;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.item_list);
final ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,R.layout.item_list);
final AutoCompleteTextView textView = (AutoCompleteTextView)
findViewById(R.id.autoCompleteTextView1);
adapter.setNotifyOnChange(true);
textView.setAdapter(adapter);
textView.addTextChangedListener(new TextWatcher() {
public void onTextChanged(CharSequence s, int start, int before, int count) {
if (count%3 == 1) {
adapter.clear();
GetPlaces task = new GetPlaces();
//now pass the argument in the textview to the task
task.execute(textView.getText().toString());
}
}
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
public void afterTextChanged(Editable s) {
}
});
}
class GetPlaces extends AsyncTask<String, Void, ArrayList<String>> {
#Override
// three dots is java for an array of strings
protected ArrayList<String> doInBackground(String... args)
{
Log.d("gottaGo", "doInBackground");
ArrayList<String> predictionsArr = new ArrayList<String>();
try
{
URL googlePlaces = new URL(
"https://maps.googleapis.com/maps/api/place/autocomplete/json?input=" +
URLEncoder.encode(args[0], "UTF-8") +
"&types=geocode&language=en&sensor=true&key= +
getResources().getString(R.string.googleAPIKey));
URLConnection tc = googlePlaces.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(
tc.getInputStream()));
String line;
StringBuffer sb = new StringBuffer();
//take Google's legible JSON and turn it into one big string.
while ((line = in.readLine()) != null) {
sb.append(line);
}
//turn that string into a JSON object
JSONObject predictions = new JSONObject(sb.toString());
//now get the JSON array that's inside that object
JSONArray ja = new JSONArray(predictions.getString("predictions"));
for (int i = 0; i < ja.length(); i++) {
JSONObject jo = (JSONObject) ja.get(i);
//add each entry to our array
predictionsArr.add(jo.getString("description"));
}
}
catch (IOException e)
{
Log.e("MultiNAV", "GetPlaces : doInBackground", e);
}
catch (JSONException e)
{
Log.e("MultiNAV", "GetPlaces : doInBackground", e);
}
return predictionsArr;
}
//then our post
#Override
protected void onPostExecute(ArrayList<String> result){
Log.d("MultiNAV", "onPostExecute : " + result.size());
//update the adapter
adapter = new ArrayAdapter<String>(getBaseContext(), R.layout.item_list);
adapter.setNotifyOnChange(true);
//attach the adapter to textview
textview.setAdapter(adapter);
for (String string : result){
Log.d("MultiNAV", "onPostExecute : result = " + string);
adapter.add(string);
adapter.notifyDataSetChanged();
}
Log.d("MultiNAV", "onPostExecute : autoCompleteAdapter" + adapter.getCount());
}
}
}
}