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Storing latitude and longitude in CSV file every 15 minutes

I want to access users location i.e latitude and longitude in every 15 minutes and store them in a CSV file. How can I do this?
I have a GPSTracker class:
public class GPSTracker extends Service implements LocationListener {
private final Context mContext;
// flag for GPS status
boolean isGPSEnabled = false;
// flag for network status
boolean isNetworkEnabled = false;
// flag for GPS status
boolean canGetLocation = false;
Location location; // location
double latitude; // latitude
double longitude; // longitude
// The minimum distance to change Updates in meters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 15; // 15 minute
// Declaring a Location Manager
protected LocationManager locationManager;
public GPSTracker(Context context) {
this.mContext = context;
getLocation();
}
public Location getLocation() {
try {
locationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
// getting GPS status
isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
// getting network status
isNetworkEnabled = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled) {
// no network provider is enabled
} else {
this.canGetLocation = true;
if (isNetworkEnabled) {
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
// if GPS Enabled get lat/long using GPS Services
if (isGPSEnabled) {
if (location == null) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return location;
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app
* */
public void stopUsingGPS() {
if (locationManager != null) {
if (checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
locationManager.removeUpdates(GPSTracker.this);
}
}
/**
* Function to get latitude
* */
public double getLatitude(){
if(location != null){
latitude = location.getLatitude();
}
// return latitude
return latitude;
}
/**
* Function to get longitude
* */
public double getLongitude(){
if(location != null){
longitude = location.getLongitude();
}
// return longitude
return longitude;
}
and in MainActivity:
File root = Environment.getExternalStorageDirectory();
File gpxfile = new File(root, "mydata.csv");
try {
writer = new FileWriter(gpxfile);
writeCsvHeader("DateTime", "Latitude", "Longitude");
writeCsvData(""+strDate,latitude,longitude);
writer.flush();
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
private void writeCsvHeader(String h1, String h2, String h3) throws IOException {
String line = String.format("%s,%s,%s\n", h1,h2,h3);
writer.write(line);
}
private void writeCsvData(String date, double lat, double lon) throws IOException {
String line = String.format("%s,%f,%f\n", date, lat, lon);
writer.write(line);
}
for CSV I have referenced
http://antipastohw.pbworks.com/w/page/41913616/Write%20CSV%20files%20onto%20SD%20Card%20Storage

For doing an repetitive task you can use Handler like,
handler.postDelayed(new Runnable(){
#Override
public void run() {
// get Location or do whatever you want
}
}, (15 * 60 * 1000));
In this case getLocation() will call after every 15 min.

May this way possible
Timer timer = new Timer();
timerTask = new TimerTask() {
Handler mnhandler = new Handler();
#Override
public void run() {
mnhandler.post(new Runnable() {
#Override
public void run() {
//Use ur method which store CSV file
}
});
}
};
timer.schedule(timerTask, start, duration);

Unable to get the correct location within indoor environment using with only WIFI

I wrote a program that provides the user's position with in a building but not the actual position . I Know that Gps does not provide high accurate result with in building . My code is as follows:
public class Internet extends Service implements LocationListener {
Context context;
LocationManager locationManager;
public Internet(Context context) {
this.context = context;
locationManager = (LocationManager) context
.getSystemService(Context.LOCATION_SERVICE);
}
Location findMeInternet() {
Boolean isInternet = false;
Location location;
isInternet = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (isInternet) {
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 3, 1, this);
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
return location;
}
}
return null;
}
//other override methods with empty bodies .
}

Try GPS provider instead of NetWORK provider ,
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,0,0, this);
if (locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null)
{
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
Make sure that device GPS is enabled. (If someone needs to downvote, please mention the reason also)

Android GPS using old locations

Im trying to learn more about location services in android and am attempting to build an app which can locate an Android device and send it's latitude and longitude to a server. I've had everything working as expected for a while, but am still being bothered by a small bug. When I send the command from the server to locate the device the first time, the device returns a recent, but old, location such as a road I drove on the same day.
On the second time the device receives a command from the server to locate the device, the device returns an accurate location.
Here is the relevant code:
LocationTracker.java
public class LocationTracker extends Service implements LocationListener {
//flag for GPS Status
boolean isGPSEnabled = false;
//flag for network status
boolean isNetworkEnabled = false;
boolean canGetLocation = false;
Location location;
double latitude;
double longitude;
//The minimum distance to change updates in metters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10*1000; //10,000 meters
//The minimum time beetwen updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 10000; // 10,000 minutes
//Declaring a Location Manager
protected LocationManager locationManager;
public void fetchLocation(Context context) {
getLocation(context);
if (canGetLocation())
{
String stringLatitude = String.valueOf(latitude);
String stringLongitude = String.valueOf(longitude);
Log.i("Location: ", stringLatitude + " " + stringLongitude);
new MyAsyncTask().execute(stringLatitude, stringLongitude);
}
else
{
// can't get location
// GPS or Network is not enabled
// Ask user to enable GPS/network in settings
Log.i("Error: ", "Cannot get location");
}
}
public Location getLocation(Context context)
{
try
{
locationManager = (LocationManager) context.getSystemService(LOCATION_SERVICE);
//getting GPS status
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
//getting network status
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled)
{
// no network provider is enabled
}
else
{
this.canGetLocation = true;
//if GPS Enabled get lat/long using GPS Services
if (isGPSEnabled)
{
if (location == null)
{
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
updateGPSCoordinates();
}
}
}
//If no GPS, get location from Network Provider
if (isNetworkEnabled && !isGPSEnabled)
{
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network");
if (locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
updateGPSCoordinates();
}
}
}
}
catch (Exception e)
{
//e.printStackTrace();
Log.e("Error : Location", "Impossible to connect to LocationManager", e);
}
return location;
}
public void updateGPSCoordinates()
{
if (location != null)
{
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app
*/
public void stopUsingGPS()
{
if (locationManager != null)
{
locationManager.removeUpdates(LocationTracker.this);
}
}
/**
* Function to get latitude
*/
public double getLatitude()
{
if (location != null)
{
latitude = location.getLatitude();
}
return latitude;
}
/**
* Function to get longitude
*/
public double getLongitude()
{
if (location != null)
{
longitude = location.getLongitude();
}
return longitude;
}
/**
* Function to check GPS/wifi enabled
*/
public boolean canGetLocation()
{
return this.canGetLocation;
}
#Override
public void onLocationChanged(Location location)
{
double newLat = location.getLatitude();
double newLong = location.getLongitude();
String stringNewLatitude = String.valueOf(newLat);
String stringNewLongitude = String.valueOf(newLong);
Log.i("New Location: ", stringNewLatitude + " " + stringNewLongitude);
new MyAsyncTask().execute(stringNewLatitude, stringNewLongitude);
}
#Override
public void onProviderDisabled(String provider)
{
}
#Override
public void onProviderEnabled(String provider)
{
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
}
public IBinder onBind(Intent intent)
{
return null;
}
Why is my location updating as an old location the first time it tries, and a correct location on the second time?
Also note that I would also like to remove requestLocationUpdates seen here:
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
because it causes a handler on dead thread warning, but when I removed it my device stopped acquiring my location. This may be part of the problem.
I would greatly appreciate any help!

It's because you're using getLastKnownLocation().
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
getLastKnownLocation(String Provider) :
Returns a Location indicating the data from the last known location fix obtained from the given provider.
This can be done without starting the provider. Note that this location could be out-of-date, for example if the device was turned off and moved to another location.

Location only refreshes when I turn GPS off

So I have a problem when trying to resolve my location. When given the command to find my location, it instead gives me the last location of where I turned my GPS off. Being able to find my coarse location using WiFi also seems to not be working.
Here is my current class
public class LocationTracker extends Service implements LocationListener {
//flag for GPS Status
boolean isGPSEnabled = false;
//flag for network status
boolean isNetworkEnabled = false;
boolean canGetLocation = false;
Location location;
double latitude;
double longitude;
//The minimum distance to change updates in metters
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; //10 metters
//The minimum time beetwen updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute
//Declaring a Location Manager
protected LocationManager locationManager;
public void fetchLocation(Context context) {
contextnormal = context;
getLocation(context);
if (canGetLocation())
{
String stringLatitude = String.valueOf(latitude);
String stringLongitude = String.valueOf(longitude);
Log.i("Location: ", stringLatitude + " " + stringLongitude);
}
else
{
// can't get location
// GPS or Network is not enabled
// Ask user to enable GPS/network in settings
Log.i("Error: ", "Cannot get location");
}
}
public Location getLocation(Context context)
{
try
{
locationManager = (LocationManager) context.getSystemService(LOCATION_SERVICE);
//getting GPS status
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
//getting network status
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled)
{
// no network provider is enabled
}
else
{
this.canGetLocation = true;
//First get location from Network Provider
if (isNetworkEnabled)
{
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network");
if (locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
updateGPSCoordinates();
}
}
//if GPS Enabled get lat/long using GPS Services
if (isGPSEnabled)
{
if (location == null)
{
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
updateGPSCoordinates();
}
}
}
}
}
catch (Exception e)
{
//e.printStackTrace();
Log.e("Error : Location", "Impossible to connect to LocationManager", e);
}
return location;
}
public void updateGPSCoordinates()
{
if (location != null)
{
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
/**
* Stop using GPS listener
* Calling this function will stop using GPS in your app
*/
public void stopUsingGPS()
{
if (locationManager != null)
{
locationManager.removeUpdates(LocationTracker.this);
}
}
/**
* Function to get latitude
*/
public double getLatitude()
{
if (location != null)
{
latitude = location.getLatitude();
}
return latitude;
}
/**
* Function to get longitude
*/
public double getLongitude()
{
if (location != null)
{
longitude = location.getLongitude();
}
return longitude;
}
/**
* Function to check GPS/wifi enabled
*/
public boolean canGetLocation()
{
return this.canGetLocation;
}
#Override
public void onLocationChanged(Location location)
{
//Want to Execute Asynctask method to HTTP post the lat and long. Is there a way `to pass in a context to do this?`
}
#Override
public void onProviderDisabled(String provider)
{
}
#Override
public void onProviderEnabled(String provider)
{
if (contextnormal != null) {
fetchLocation(contextnormal);
}
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
}
#Override
public IBinder onBind(Intent intent)
{
return null;
}
I would guess the problem lies in these lines
if (isGPSEnabled)
{
if (location == null)
{
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS Enabled", "GPS Enabled");
if (locationManager != null)
{
location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
updateGPSCoordinates();
}
}
And for some reason it is giving the last known location as the last time the GPS was turned on. Any ideas as to why it is doing that instead of giving the last known location as the present location if the GPS is on?
EDIT:
Implementing the following method and testing:
#Override
public void onLocationChanged(Location location)
{
double newLat = location.getLatitude();
double newLong = location.getLongitude();
String stringNewLatitude = String.valueOf(newLat);
String stringNewLongitude = String.valueOf(newLong);
new MyAsyncTask().execute(stringNewLatitude, stringNewLongitude);
}

You can't just query the location manager for its last known location repeatedly, that will only get you the last known location. It sounds like what you are trying to do is get location updates as you move around.
In this case, you will need to register for location updates, as you tried with your line:
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
You are on the right track here, but what is this (the last argument on the function call [yes I know it is a reference to the current class...])? The last argument is supposed to be an intent or a callback where the updates will be broadcast to. It doesn't appear that you have implemented that from the code you provided.
Change your this argument to a class which implements LocationListener. The location updates will come to the onLocationChanged method where you can then process them as you see fit. A simple way to do this is to add a nested inner class which implements the listener, then you can just create an instance of that class and pass it to the location manager, in place of your current this argument.
EDIT
OK, so you are implementing the thing correctly, but blisfully ignoring the location updates, don't do that. The service you have is a Context -- so you can pass that around as you see fit, although it may be better to use:
this.getApplicationContext();
If you are passing it to some long running thing. What I would recommend is to queue your location updates when the arrive in onLocationChanged(). After queuing the location, signal a background worker thread (or AsyncTask) to actually post the location to your web service.
Also, don't override onBind and return null. Just don't override it.

getlastknownlocation always return null after I re-install the apk file via eclipse

Recently, I created a simple application to get the GPS location and display it on an Android phone.
In the beginning I was able to get the location after a few tries. But, after I reinstalled the APK file, the getLastKnownLocation() always returns a null value.
The development environment:
API 10 Gingerbread 2.3.6
GPS provider is used
Below is the code I applied to my Android project:
public class MyActivity extends MapActivity {
protected void onCreate(Bundle savedInstanceState) {
mapView = (MapView) findViewById(R.id.myTripMap);
mapController = mapView.getController();
mapView.setSatellite(false);
mapView.setStreetView(true);
mapView.displayZoomControls(false);
mapView.setBuiltInZoomControls(true);//
mapView.setClickable(true);
mapController.setZoom(14);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
provider = locationManager.getBestProvider(criteria, true);
location = locationManager.getLastKnownLocation(provider);
updateMyCurrentLoc(location);
locationManager.requestLocationUpdates(provider, 2, 1, locationListener);
}
private final LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
updateMyCurrentLoc(location);
}
public void onProviderDisabled(String provider) {
updateMyCurrentLoc(null);
}
public void onProviderEnabled(String provider) {
}
public void onStatusChanged(String provider, int status,
Bundle extras) {
}
};
private void updateMyCurrentLoc(Location location) {
if (location != null) {
// other codes to get the address and display
Toast.makeText(getBaseContext(), "provider used : " + provider).show(); //testing purpose
} else {
str = "No location found";
Toast.makeText(getBaseContext(), str, Toast.LENGTH_SHORT).show();
}
}
}
Can anyone suggest a possible solution to solve the null value returned by getLastKnownLocation()?

Try Following Code
LocationManager locationManager = (LocationManager) getActivity()
.getSystemService(Context.LOCATION_SERVICE);
String locationProvider = LocationManager.NETWORK_PROVIDER;
Location lastlocation = locationManager.getLastKnownLocation(locationProvider);
String CurLat = String.valueOf(lastlocation.getLatitude());
String Curlongi= String.valueOf(lastlocation.getLongitude());

This solution is my little improvement for code by Ravi Tamada.
public Location getLocation() {
int MIN_TIME_BW_UPDATES = 10000;
int MIN_DISTANCE_CHANGE_FOR_UPDATES = 10000;
try {
locationManager = (LocationManager) getApplicationContext()
.getSystemService(LOCATION_SERVICE);
boolean isGPSEnabled = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
boolean isPassiveEnabled = locationManager
.isProviderEnabled(LocationManager.PASSIVE_PROVIDER);
boolean isNetworkEnabled = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (isGPSEnabled || isNetworkEnabled || isPassiveEnabled) {
this.canGetLocation = true;
// if GPS Enabled get lat/long using GPS Services
if (isGPSEnabled && location == null) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("GPS", "GPS Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
}
}
if (isPassiveEnabled && location == null) {
locationManager.requestLocationUpdates(
LocationManager.PASSIVE_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);
}
}
if (isNetworkEnabled && location == null) {
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
Log.d("Network", "Network Enabled");
if (locationManager != null) {
location = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
}
}
}else{
return null;
}
} catch (Exception e) {
e.printStackTrace();
}

You just need to add one more line into the code
if (locationManager != null) {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
location = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
} else {
Toast.makeText(
mContext,
"Location Null", Toast.LENGTH_SHORT).show();
}
}

I got the same issue after re-install via eclipse.
I solved going to Android settings / Security / app permissions and confirm location permissions to the application.