How do I get the current GPS location programmatically in Android?
I need to get my current location using GPS programmatically. How can i achieve it?
I have created a small application with step by step description to get current location's GPS coordinates.
Complete example source code is in Get Current Location coordinates , City name - in Android.
See how it works:
All we need to do is add this permission in the manifest file:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
And create a LocationManager instance like this:
LocationManager locationManager = (LocationManager)
getSystemService(Context.LOCATION_SERVICE);
Check if GPS is enabled or not.
And then implement LocationListener and get coordinates:
LocationListener locationListener = new MyLocationListener();
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, 5000, 10, locationListener);
Here is the sample code to do so
/*---------- Listener class to get coordinates ------------- */
private class MyLocationListener implements LocationListener {
@Override
public void onLocationChanged(Location loc) {
editLocation.setText("");
pb.setVisibility(View.INVISIBLE);
Toast.makeText(
getBaseContext(),
"Location changed: Lat: " + loc.getLatitude() + " Lng: "
+ loc.getLongitude(), Toast.LENGTH_SHORT).show();
String longitude = "Longitude: " + loc.getLongitude();
Log.v(TAG, longitude);
String latitude = "Latitude: " + loc.getLatitude();
Log.v(TAG, latitude);
/*------- To get city name from coordinates -------- */
String cityName = null;
Geocoder gcd = new Geocoder(getBaseContext(), Locale.getDefault());
List<Address> addresses;
try {
addresses = gcd.getFromLocation(loc.getLatitude(),
loc.getLongitude(), 1);
if (addresses.size() > 0) {
System.out.println(addresses.get(0).getLocality());
cityName = addresses.get(0).getLocality();
}
}
catch (IOException e) {
e.printStackTrace();
}
String s = longitude + "n" + latitude + "nnMy Current City is: "
+ cityName;
editLocation.setText(s);
}
@Override
public void onProviderDisabled(String provider) {}
@Override
public void onProviderEnabled(String provider) {}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {}
}
Here is additional information for other answers.
Since Android has
GPS_PROVIDER and NETWORK_PROVIDER
you can register to both and start fetch events from onLocationChanged(Location location) from two at the same time. So far so good. Now the question do we need two results or we should take the best. As I know GPS_PROVIDER results have better accuracy than NETWORK_PROVIDER .
Let's define Location field:
private Location currentBestLocation = null;
Before we start listen on Location change we will implement the following method. This method returns the last known location, between the GPS and the network one. For this method newer is best.
/**
* @return the last know best location
*/
private Location getLastBestLocation() {
Location locationGPS = mLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
Location locationNet = mLocationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
long GPSLocationTime = 0;
if (null != locationGPS) { GPSLocationTime = locationGPS.getTime(); }
long NetLocationTime = 0;
if (null != locationNet) {
NetLocationTime = locationNet.getTime();
}
if ( 0 < GPSLocationTime - NetLocationTime ) {
return locationGPS;
}
else {
return locationNet;
}
}
Each time when we retrieve a new location we will compare it with our previous result.
...
static final int TWO_MINUTES = 1000 * 60 * 2;
...
I add a new method to onLocationChanged :
@override
public void onLocationChanged(Location location) {
makeUseOfNewLocation(location);
if(currentBestLocation == null){
currentBestLocation = location;
}
....
}
/**
* This method modify the last know good location according to the arguments.
*
* @param location The possible new location.
*/
void makeUseOfNewLocation(Location location) {
if ( isBetterLocation(location, currentBestLocation) ) {
currentBestLocation = location;
}
}
....
/** Determines whether one location reading is better than the current location fix
* @param location The new location that you want to evaluate
* @param currentBestLocation The current location fix, to which you want to compare the new one.
*/
protected boolean isBetterLocation(Location location, Location currentBestLocation) {
if (currentBestLocation == null) {
// A new location is always better than no location
return true;
}
// Check whether the new location fix is newer or older
long timeDelta = location.getTime() - currentBestLocation.getTime();
boolean isSignificantlyNewer = timeDelta > TWO_MINUTES;
boolean isSignificantlyOlder = timeDelta < -TWO_MINUTES;
boolean isNewer = timeDelta > 0;
// If it's been more than two minutes since the current location, use the new location,
// because the user has likely moved.
if (isSignificantlyNewer) {
return true;
// If the new location is more than two minutes older, it must be worse.
} else if (isSignificantlyOlder) {
return false;
}
// Check whether the new location fix is more or less accurate
int accuracyDelta = (int) (location.getAccuracy() - currentBestLocation.getAccuracy());
boolean isLessAccurate = accuracyDelta > 0;
boolean isMoreAccurate = accuracyDelta < 0;
boolean isSignificantlyLessAccurate = accuracyDelta > 200;
// Check if the old and new location are from the same provider
boolean isFromSameProvider = isSameProvider(location.getProvider(),
currentBestLocation.getProvider());
// Determine location quality using a combination of timeliness and accuracy
if (isMoreAccurate) {
return true;
} else if (isNewer && !isLessAccurate) {
return true;
} else if (isNewer && !isSignificantlyLessAccurate && isFromSameProvider) {
return true;
}
return false;
}
/** Checks whether two providers are the same */
private boolean isSameProvider(String provider1, String provider2) {
if (provider1 == null) {
return provider2 == null;
}
return provider1.equals(provider2);
}
....
You can find the location either by GPS_PROVIDER or NETWORK_PROVIDER .
Overview of location services in Android.
Here is one example which try to find the location using GPS. If your GPS is not available then try to use network for find the location.
GPSTracker.java
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 * 1; // 1 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 latitude/longitude 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){
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;
}
/**
* Function to check GPS/Wi-Fi enabled
* @return boolean
* */
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* Function to show settings alert dialog.
* On pressing the Settings button it will launch Settings Options.
* */
public void showSettingsAlert(){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("GPS is settings");
// Setting Dialog Message
alertDialog.setMessage("GPS is not enabled. Do you want to go to settings menu?");
// On pressing the Settings button.
alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
// On pressing the cancel button
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
@Override
public void onLocationChanged(Location location) {
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public IBinder onBind(Intent arg0) {
return null;
}
}
Activity -AndroidGPSTrackingActivity.java
public class AndroidGPSTrackingActivity extends Activity {
Button btnShowLocation;
// GPSTracker class
GPSTracker gps;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
btnShowLocation = (Button) findViewById(R.id.btnShowLocation);
// Show location button click event
btnShowLocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
// Create class object
gps = new GPSTracker(AndroidGPSTrackingActivity.this);
// Check if GPS enabled
if(gps.canGetLocation()) {
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();
// n is for new line
Toast.makeText(getApplicationContext(), "Your Location is - nLat: " + latitude + "nLong: " + longitude, Toast.LENGTH_LONG).show();
} else {
// Can't get location.
// GPS or network is not enabled.
// Ask user to enable GPS/network in settings.
gps.showSettingsAlert();
}
}
});
}
}
Layout- main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<Button android:id="@+id/btnShowLocation"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Show Location"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"/>
</RelativeLayout>
AndroidManifest.xml
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
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