Develop Reference

How to refresh marker in Android Google Maps view?

How can I refresh the marker position (for example, when user is moving) on Android maps?
I set up the refresh time for 3 seconds in locationManager.requestLocationUpdates but it seems that it's not working.
Here is my 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 = 50; // 3 seconds
// 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;
// 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);
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;
}
public void stopUsingGPS() {
if (locationManager != null) {
locationManager.removeUpdates(GPSTracker.this);
}
}
public double getLatitude() {
if (location != null) {
latitude = location.getLatitude();
}
// return latitude
return latitude;
}
public double getLongitude() {
if (location != null) {
longitude = location.getLongitude();
}
// return longitude
return longitude;
}
public boolean canGetLocation() {
return this.canGetLocation;
}
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 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 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;
}
}
And here is my Maps Activity where I create map and add a marker to it:
public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {
private GoogleMap mMap;
private final static int REQUEST_CODE_ASK_PERMISSIONS = 1;
private static final String[] REQUIRED_SDK_PERMISSIONS = new String[]{
Manifest.permission.ACCESS_FINE_LOCATION,
Manifest.permission.ACCESS_COARSE_LOCATION,
Manifest.permission.INTERNET,
Manifest.permission.ACCESS_NETWORK_STATE};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
checkPermissions();
// 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);
}
#Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
mapsCreate();
}
public void mapsCreate() {
GPSTracker tracker = new GPSTracker(MapsActivity.this);
double lat = tracker.getLatitude();
double lng = tracker.getLongitude();
// Add a marker for current location and move the camera
LatLng currentLocation = new LatLng(lat, lng);
mMap.addMarker(new MarkerOptions().position(currentLocation).title("Current Location Marker"));
mMap.moveCamera(CameraUpdateFactory.newLatLng(currentLocation));
}
protected boolean checkPermissions() {
final List<String> missingPermissions = new ArrayList<String>();
// check all required dynamic permissions
for (final String permission : REQUIRED_SDK_PERMISSIONS) {
final int result = ContextCompat.checkSelfPermission(this, permission);
if (result != PackageManager.PERMISSION_GRANTED) {
missingPermissions.add(permission);
}
}
if (!missingPermissions.isEmpty()) {
// request all missing permissions
final String[] permissions = missingPermissions
.toArray(new String[missingPermissions.size()]);
ActivityCompat.requestPermissions(this, permissions, REQUEST_CODE_ASK_PERMISSIONS);
} else {
final int[] grantResults = new int[REQUIRED_SDK_PERMISSIONS.length];
Arrays.fill(grantResults, PackageManager.PERMISSION_GRANTED);
onRequestPermissionsResult(REQUEST_CODE_ASK_PERMISSIONS, REQUIRED_SDK_PERMISSIONS,
grantResults);
return true;
}
return true;
}
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String permissions[],
#NonNull int[] grantResults) {
switch (requestCode) {
case REQUEST_CODE_ASK_PERMISSIONS:
for (int index = permissions.length - 1; index >= 0; --index) {
if (grantResults[index] != PackageManager.PERMISSION_GRANTED) {
// exit the app if one permission is not granted
Toast.makeText(this, "Required permission '" + permissions[index]
+ "' not granted, exiting", Toast.LENGTH_LONG).show();
finish();
return;
}
}
// all permissions were granted
break;
}
}
Any help would be much appreciated! Thank you

Save the marker object after adding to maps.
myMarker = mMap.addMarker(new MarkerOptions().position(currentLocation).title("Current Location Marker"));
After getting new location in location updates callback update marker's position.
.....
myMarker.setPosition(newLatLng);

Getting Latitude and longitude with GPS as 0,0

I am trying to get location in app and when i turn GPS on for the very first time.
It shows latitude and longitude 0,0. but when i check again it shows correctly.
I am sharing my code with you please help me to find out where is the problem.
this is my code for GPS tracker.
I have tried many solutions but did not get anything working.
What is the reason of getting o first time???
public class LocationTrack extends Service implements LocationListener {
private final Context mContext;
boolean checkGPS = false;
boolean checkNetwork = false;
boolean canGetLocation = false;
Location loc;
double latitude;
double longitude;
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 70;
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1;
protected LocationManager locationManager;
public LocationTrack(Context mContext) {
this.mContext = mContext;
getLocation();
}
private Location getLocation() {
try {
locationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
// get GPS status
checkGPS = locationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
// get network provider status
checkNetwork = locationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!checkGPS && !checkNetwork) {
Toast.makeText(mContext, "No Service Provider is available", Toast.LENGTH_SHORT).show();
} else {
this.canGetLocation = true;
// if GPS Enabled get lat/long using GPS Services
if (checkGPS) {
if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
//public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
}
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
if (locationManager != null) {
loc = locationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (loc != null) {
latitude = loc.getLatitude();
longitude = loc.getLongitude();
}
}
}
if (checkNetwork) {
if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
}
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
if (locationManager != null) {
loc = locationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
}
if (loc != null) {
latitude = loc.getLatitude();
longitude = loc.getLongitude();
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return loc;
}
public double getLongitude() {
if (loc != null) {
longitude = loc.getLongitude();
}
return longitude;
}
public double getLatitude() {
if (loc != null) {
latitude = loc.getLatitude();
}
return latitude;
}
public boolean canGetLocation() {
return this.canGetLocation;
}
public void showSettingsAlert() {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
alertDialog.setTitle("GPS is not Enabled!");
alertDialog.setMessage("Do you want to turn on GPS?");
alertDialog.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
alertDialog.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
alertDialog.show();
}
public void stopListener() {
if (locationManager != null) {
if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
locationManager.removeUpdates(LocationTrack.this);
}
}
#Override
public IBinder onBind(Intent intent) {
return null;
}
#Override
public void onLocationChanged(Location location) {
this.loc = location;
getLatitude();
getLongitude();
}
#Override
public void onStatusChanged(String s, int i, Bundle bundle) {
}
#Override
public void onProviderEnabled(String s) {
}
#Override
public void onProviderDisabled(String s) {
}
}
Manifest file with all permissions....
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.user.attendenceapplication">
<uses-feature android:name="android.hardware.location.gps" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<application
android:allowBackup="true"
android:icon="#drawable/logodki"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".SplashScreen">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

Many GPS receivers will return 0 when queried for latitude or longitude before they have a fix, it's nothing to do with your code.
See this question:
GPS Intermediate Driver Constantly Return 0 0 LAT LNG

Sorry for late reply. All are fine with your code.
just do one small change as below:
set MIN_TIME_BW_UPDATES = 0
and
set MIN_DISTANCE_CHANGE_FOR_UPDATES = 0

How to solve Call Requires Permission [Android]

I'm having trouble with to solve the current location problem where the LocationManager gives error of this:
I had added this code but the it need return value.Should I just return null or .. ?
Below are my code for the location:
public class GPSService extends Service implements LocationListener {
// saving the context for later use
private final Context mContext;
// if GPS is enabled
boolean isGPSEnabled = false;
// if Network is enabled
boolean isNetworkEnabled = false;
// if Location co-ordinates are available using GPS or Network
public boolean isLocationAvailable = false;
// Location and co-ordinates coordinates
Location mLocation;
double mLatitude;
double mLongitude;
// Minimum time fluctuation for next update (in milliseconds)
private static final long TIME = 30000;
// Minimum distance fluctuation for next update (in meters)
private static final long DISTANCE = 20;
// Declaring a Location Manager
protected LocationManager mLocationManager;
public GPSService(Context context) {
this.mContext = context;
mLocationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
}
/**
* Returs the Location
*
* #return Location or null if no location is found
*/
public Location getLocation() {
try {
// If reaching here means, we were not able to get location neither
// from GPS not Network,
if (!isGPSEnabled) {
// so asking user to open GPS
askUserToOpenGPS();
}
mLocationManager = (LocationManager) mContext
.getSystemService(LOCATION_SERVICE);
// Getting GPS status
isGPSEnabled = mLocationManager
.isProviderEnabled(LocationManager.GPS_PROVIDER);
if ( Build.VERSION.SDK_INT >= 23 &&
ContextCompat.checkSelfPermission( getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION ) != PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission( getApplicationContext(), android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return ;
// If GPS enabled, get latitude/longitude using GPS Services
if (isGPSEnabled) {
mLocationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER, TIME, DISTANCE, this);
if (mLocationManager != null) {
mLocation = mLocationManager
.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (mLocation != null) {
mLatitude = mLocation.getLatitude();
mLongitude = mLocation.getLongitude();
isLocationAvailable = true; // setting a flag that
// location is available
return mLocation;
}
}
}
// If we are reaching this part, it means GPS was not able to fetch
// any location
// Getting network status
isNetworkEnabled = mLocationManager
.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (isNetworkEnabled) {
mLocationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, TIME, DISTANCE, this);
if (mLocationManager != null) {
mLocation = mLocationManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (mLocation != null) {
mLatitude = mLocation.getLatitude();
mLongitude = mLocation.getLongitude();
isLocationAvailable = true; // setting a flag that
// location is available
return mLocation;
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
// if reaching here means, location was not available, so setting the
// flag as false
isLocationAvailable = false;
return null;
}
}
/**
* Gives you complete address of the location
*
* #return complete address in String
*/
public String getLocationAddress() {
if (isLocationAvailable) {
Geocoder geocoder = new Geocoder(mContext, Locale.getDefault());
// Get the current location from the input parameter list
// Create a list to contain the result address
List<Address> addresses = null;
try {
/*
* Return 1 address.
*/
addresses = geocoder.getFromLocation(mLatitude, mLongitude, 1);
} catch (IOException e1) {
e1.printStackTrace();
return ("IO Exception trying to get address:" + e1);
} catch (IllegalArgumentException e2) {
// Error message to post in the log
String errorString = "Illegal arguments "
+ Double.toString(mLatitude) + " , "
+ Double.toString(mLongitude)
+ " passed to address service";
e2.printStackTrace();
return errorString;
}
// If the reverse geocode returned an address
if (addresses != null && addresses.size() > 0) {
// Get the first address
Address address = addresses.get(0);
/*
* Format the first line of address (if available), city, and
* country name.
*/
String addressText = String.format(
"%s, %s, %s",
// If there's a street address, add it
address.getMaxAddressLineIndex() > 0 ? address
.getAddressLine(0) : "",
// Locality is usually a city
address.getLocality(),
// The country of the address
address.getCountryName());
// Return the text
return addressText;
} else {
return "No address found by the service: Note to the developers, If no address is found by google itself, there is nothing you can do about it.";
}
} else {
return "Location Not available";
}
}
/**
* get latitude
*
* #return latitude in double
*/
public double getLatitude() {
if (mLocation != null) {
mLatitude = mLocation.getLatitude();
}
return mLatitude;
}
/**
* get longitude
*
* #return longitude in double
*/
public double getLongitude() {
if (mLocation != null) {
mLongitude = mLocation.getLongitude();
}
return mLongitude;
}
/**
* close GPS to save battery
*/
public void closeGPS() {
if (mLocationManager != null) {
try {
mLocationManager.removeUpdates(GPSService.this);
} catch (SecurityException e) {
Log.e("PERMISSION_EXCEPTION", "PERMISSION_NOT_GRANTED");
}
}
}
/**
* show settings to open GPS
*/
public void askUserToOpenGPS() {
AlertDialog.Builder mAlertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
mAlertDialog.setTitle("Location not available, Open GPS?")
.setMessage("Activate GPS to use use location services?")
.setPositiveButton("Open Settings", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
})
.setNegativeButton("Cancel",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
}).show();
}
/**
* Updating the location when location changes
*/
#Override
public void onLocationChanged(Location location) {
mLatitude = location.getLatitude();
mLongitude = location.getLongitude();
}
#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;
}
}
I also had added these codes in Android Manifest:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

Specify the following permissions in your manifest file
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
and check runtime permission for API 23 above
if ( Build.VERSION.SDK_INT >= 23 &&
ContextCompat.checkSelfPermission( context, android.Manifest.permission.ACCESS_FINE_LOCATION ) != PackageManager.PERMISSION_GRANTED &&
ContextCompat.checkSelfPermission( context, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return null;
}

Try to check permission for location and ask for same by using this code.
int permissionCheck = ContextCompat.checkSelfPermission(MainActivity.this, android.Manifest.permission.ACCESS_FINE_LOCATION);
int permissionCheck1 = ContextCompat.checkSelfPermission(MainActivity.this, android.Manifest.permission.ACCESS_COARSE_LOCATION);
if (permissionCheck == PackageManager.PERMISSION_GRANTED && permissionCheck1 == PackageManager.PERMISSION_GRANTED) {
startService(new Intent(MainActivity.this, TrackingService.class));
locationRelatedServices();
} else {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.ACCESS_COARSE_LOCATION, android.Manifest.permission.ACCESS_FINE_LOCATION}, PermissionInts.LOCATION_CODE);
}
Once the user gives permission you can use this code to run your project :
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case PermissionInts.LOCATION_CODE:
locationRelatedServices();
}
break;
}

Your method returns a Location object, when you couldn't fetch the location then you need to return null (when the permission is not granted).
Use
return null; rather than return;

Use this source code
//Enables location permission for Marshmallow
public void getPermissionLocation(){
// 1) Use the support library version ContextCompat.checkSelfPermission(...) to avoid
// checking the build version since Context.checkSelfPermission(...) is only available
// in Marshmallow
// 2) Always check for permission (even if permission has already been granted)
// since the user can revoke permissions at any time through Settings
if (ContextCompat.checkSelfPermission(PrimecardSplashscreen.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ContextCompat.checkSelfPermission(PrimecardSplashscreen.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// The permission is NOT already granted.
// Check if the user has been asked about this permission already and denied
// it. If so, we want to give more explanation about why the permission is needed.
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (shouldShowRequestPermissionRationale(
Manifest.permission.ACCESS_FINE_LOCATION)) {
// Show our own UI to explain to the user why we need to read the contacts
// before actually requesting the permission and showing the default UI
}
}
}
// Fire off an async request to actually get the permission
// This will show the standard permission request dialog UI
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
AppData.READ_LOCATION_PERMISSIONS_REQUEST);
}
}
}
#Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
// Make sure it's our original ACCESS_FINE_LOCATION request
if (requestCode == AppData.READ_LOCATION_PERMISSIONS_REQUEST) {
if (grantResults.length == 1 &&
grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(PrimecardSplashscreen.this, "Read Location permission granted", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(PrimecardSplashscreen.this, "Read Location permission denied", Toast.LENGTH_SHORT).show();
}
} else {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}

finding location from requestLocationUpdates() from GPS not working

I am creating a map application, which gets location from GPS, i'm finding location from requestLocationUpdates(), but i'm not getting any response from GPS provider, however when i'am using network provider i'am getting location, can anyone help where i'm wrong,
Also i'am new to android app development, so i'll appreciate any tips to optimize my code(make more efficient with less mess),
Here's my code :
public void trackLocation(){
if (ContextCompat.checkSelfPermission(activity.getApplicationContext(), Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
locationManager = (LocationManager) activity.getSystemService(Context.LOCATION_SERVICE);
boolean flag;
Boolean dlg;
flag = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
if (flag) {
Log.v("function", "onClick");
myLocationListener = new MyLocationListener();
dlg = true;
} else {
dlg = gpsDialog();
progressBar.setVisibility(View.GONE);
}
Log.d("maps", "Requesting location updates");
if(dlg) {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, myLocationListener);
}
}
}
public class MyLocationListener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
if (ActivityCompat.checkSelfPermission(MapsActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(MapsActivity.this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}
Log.d("maps", "on location changed : "+location.getLatitude() + "---"+ location.getLongitude());
locationManager.removeUpdates(myLocationListener);
}
#Override
public void onStatusChanged(String s, int i, Bundle bundle) {
Log.d("maps" , "Status Changed");
}
#Override
public void onProviderEnabled(String s) {
Log.d("maps" , "Provider Enabled");
}
#Override
public void onProviderDisabled(String s) {
Log.d("maps" , "Provider Disabled");
}
}
public Boolean gpsDialog(){
AlertDialog.Builder builder = new AlertDialog.Builder(activity);
builder.setMessage("Do you want to start GPS?")
.setCancelable(false)
.setTitle("GPS DISABLED")
.setPositiveButton("Yes",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// finish the current activity
Intent myIntent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
activity.startActivity(myIntent);
dialog.cancel();
}
})
.setNegativeButton("No",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// cancel the dialog box
dialog.cancel();
}
});
AlertDialog alert = builder.create();
alert.show();
progressBar.setVisibility(View.GONE);
return false;
}

Google maps uses user's lastKnownLocation for location, If the lastknownLocation is unknown it takes time to fetch location through different provider say GPS or Network, whichever is easy. I would suggest to use lastKnownLocation as base location and update it with LocationListener. It is most optimized way of processing location.
if (ActivityCompat.checkSelfPermission
(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED
&&
ActivityCompat.checkSelfPermission
(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED)
{
requestPermissions(new String[]{
Manifest.permission.ACCESS_COARSE_LOCATION,
Manifest.permission.ACCESS_FINE_LOCATION
}, 1);
}
else {
// enable location buttons
googleMap.setMyLocationEnabled(true);
googleMap.getUiSettings().setMyLocationButtonEnabled(true);
// fetch last location if any from provider - GPS.
final LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
final Location loc = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
//if last known location is not available
if (loc == null) {
final LocationListener locationListener = new LocationListener() {
#Override
public void onLocationChanged(final Location location) {
// getting location of user
final double latitude = location.getLatitude();
final double longitude = location.getLongitude();
//do something with Lat and Lng
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
//when user enables the GPS setting, this method is triggered.
}
#Override
public void onProviderDisabled(String provider) {
//when no provider is available in this case GPS provider, trigger your gpsDialog here.
}
};
//update location every 10sec in 500m radius with both provider GPS and Network.
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 10*1000, 500, locationListener);
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 10000, 500, locationListener);
}
else {
//do something with last known location.
// getting location of user
final double latitude = loc.getLatitude();
final double longitude = loc.getLongitude();
}
}
Permission handling:
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
switch (requestCode) {
case 1:
if (grantResults[0] != PackageManager.PERMISSION_GRANTED){
//do something
}
default:
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
}

Your code is correct. GPS usually doesn't give you any info within the building, if you try to test the app outside, you will get the results.

firstly check gps_enabled return true or not.
LocationManager lm = (LocationManager) mCtx
.getSystemService(Context.LOCATION_SERVICE);
gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
network_enabled = lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
By this code you get accurate lat , long
Location net_loc = null, gps_loc = null, finalLoc = null;
if (gps_enabled)
gps_loc = lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (network_enabled)
net_loc = lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (gps_loc != null && net_loc != null) {
if (gps_loc.getAccuracy() >= net_loc.getAccuracy())
finalLoc = gps_loc;
else
finalLoc = net_loc;
// I used this just to get an idea (if both avail, its upto you which you want to take as I taken location with more accuracy)
} else {
if (gps_loc != null) {
finalLoc = net_loc;
} else if (net_loc != null) {
finalLoc = gps_loc;
}
}

android -LocationManager return 0.0 for latitude and longitude

I want to get current latitude and longitude when user clicks on a button . to do so ,I've written these codes :
LocationManager mlocManager=null;
LocationListener mlocListener;
mlocManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
mlocListener = new MyLocationListener();
mlocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, mlocListener);
if (mlocManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
Log.v("this",MyLocationListener.latitude+ " lat");
if(MyLocationListener.latitude>0){
in = new Intent(DrawerActivity.this, Barbers.class);
in.putExtra("w", "nearest");
in.putExtra("latitude",Double.toString(MyLocationListener.latitude));
in.putExtra("longitude",Double.toString(MyLocationListener.longitude));
startActivity(in);
}else{
MyToast.makeText(DrawerActivity.this, Z_Farsi.Convert(getString(R.string.gpsfinding)));
}
} else {
MyToast.makeText(DrawerActivity.this, Z_Farsi.Convert(getString(R.string.gpsoffline)));
}
The gps is on and the current location is showing on google map perfectly .
What is the problem ? why it returns 0.0 ?
how to solve this ?

getLastKnownLocation is missing. You should have something like this :
Location location = null;
if (mlocManager!= null) {
location = mlocManager
.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}

This file will do the work for you. It will get the data from network-operator or GPS.
GPSTracker.java
public class GpsTracker extends Service implements LocationListener {
private final Context mContext;
boolean isGPSEnabled = false;
boolean isNetworkEnabled = false;
boolean canGetLocation = false;
Location location;
double latitude;
double longitude;
private final long MIN_DISTANCE = 10;
private final long MIN_TIME = 30;
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 enabled
} else {
this.canGetLocation = true;
// first get location from network provider
if (isNetworkEnabled) {
if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return null;
}
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME, MIN_DISTANCE, 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 provider
if (isGPSEnabled) {
if (location == null) {
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME, MIN_DISTANCE, this);
Log.d("GPS provider", "GPS provider");
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 (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
locationManager.removeUpdates(GpsTracker.this);
}
}
// functions to get latitude and longitude
public double getLatitude()
{
if(location != null){
latitude = location.getLatitude();
}
return latitude;
}
public double getLongitude()
{
if(location != null){
longitude = location.getLongitude();
}
return longitude;
}
// function to check whether GPS/WiFi is enabled
public boolean canGetLocation()
{
return this.canGetLocation;
}
/* Function to show alert dialog
* on pressing settings button will launch settings options */
public void showAlertDialog()
{
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
alertDialog.setTitle("GPS Settings").setMessage("GPS not Enabled. /n Want to enable it ? ").setCancelable(false);
alertDialog.setPositiveButton("Settings", new OnClickListener() {
#Override
public void onClick(DialogInterface arg0, int arg1) {
// Implicit intent
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
mContext.startActivity(intent);
}
});
alertDialog.setNegativeButton("No", new OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int arg1) {
dialog.cancel();
}
});
alertDialog.show();
}
#Override
public IBinder onBind(Intent arg0) {
// TODO Auto-generated method stub
return null;
}
#Override
public void onLocationChanged(Location arg0) {
// TODO Auto-generated method stub
}
#Override
public void onProviderDisabled(String arg0) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String arg0) {
// TODO Auto-generated method stub
}
#Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
// TODO Auto-generated method stub
}
}

Try like this
manager.requestLocationUpdates("gps", 10, 10, new LocationListener() {
#Override
public void onLocationChanged(Location location) {
double lat=location.getLatitude();
double lon=location.getLognitude()
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
});

What I have come to notice with location features is that you cannot acquire a user location instantly. You have to wait for the device to give you the location.
Normally, I would have my code in my Application class then for example when a user clicks the button, you call a method inside the application class and let the user know (through a progress dialog??) that they should wait for the latitude and longitude to be acquired.
Next thing would be to use an event to notify the activity or fragment of the location availability then dismissing the progress dialog once you have your data.
Just know that you cannot easily get the current location when you want like immediately. Sometimes, when indoors, it doesn't even work as expected.
Good luck!