im testing my app in a real device, and a get a error and dont know how to fix.
My app asks for permission to location on android, when install the application asks to allow access. To locate the position the first time you need to click on the location button.
My problem is this: If GPS is disabled, the app does not find the right position, even after activation, getting as latitude and longitude 0.0.
When you click the button the app checks if it is activated and asks to activate, but even activating the location is the same as 0.0
If you install the app with GPS enabled, this problem does not occur.
Can someone help me?
im using this code to location button
public void btnlocalizacao(View view) {
gps = new GPSTracker(MainActivity.this);
// check if GPS enabled
if (gps.canGetLocation()) {
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();
CameraPosition newCamPos = new CameraPosition(new LatLng(latitude, longitude),
15.5f,
googleMap.getCameraPosition().tilt, //use old tilt
googleMap.getCameraPosition().bearing); //use old bearing
googleMap.animateCamera(CameraUpdateFactory.newCameraPosition(newCamPos), 2000, null);
} else {
gps.showSettingsAlert();
}
}
and this is the gps 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 = 1; // 10 meters
// The minimum time between updates in milliseconds
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 ; // 1 minute
// Declaring a Location Manager
protected LocationManager locationManager;
Criteria criteria = new Criteria();
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.getBestProvider(criteria, true));
//location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
Log.d("Localização", latitude + " " + longitude);
}
}
}
// 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.getBestProvider(criteria, false));
//location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
Log.d("Localização", latitude + " " + longitude);
}
}
}
}
}
} 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/wifi enabled
* @return boolean
* */
public boolean canGetLocation() {
return this.canGetLocation;
}
/**
* Function to show settings alert dialog
* On pressing Settings button will lauch Settings Options
* */
public void showSettingsAlert(){
AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);
// Setting Dialog Title
alertDialog.setTitle("ALerta de GPS");
// Setting Dialog Message
alertDialog.setMessage("GPS não esta ativado, gostaria de ativar?");
// On pressing Settings button
alertDialog.setPositiveButton("Configurações", 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("Cancelar", 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;
}
}
My problem is this: If GPS is disabled, the app does not find the right position, even after activation, getting as latitude and longitude 0.0.
It is all works as intended. The fact you are granted location permission means you are permitted to obtain the location IF and only IF it is available. It means nothing more, especially it does NOT guarantee nor even mean that you will ever get any coordinates from the system (user may i.e. simply do not use GPS receiver).