Q: Android GPS location
I’m trying to access my device’s GPS location so I can use it to load Google map on user coordinates. I followed various guides but I don’t seem to get any correct values.
The app doesn’t crash, it just shows a zero
Here is the code for my map activity:
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;
public class Maps extends ActionBarActivity {
Button btnLocation;
GPSTracker gps;
private GoogleMap map;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Hide action bar before Activity load
getSupportActionBar().hide();
setContentView(R.layout.activity_maps);
btnLocation = (Button) findViewById(R.id.btnLocation);
btnLocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
gps = new GPSTracker(Maps.this);
if(gps.canGetLocation()){
double latitude = gps.getLatitude();
double longitude = gps.getLongitude();
Toast.makeText(getApplicationContext(),
"Your location is -\nLat: " + latitude +
"\nLong: " + longitude, Toast.LENGTH_LONG).show();
} else {
gps.showSettingsAlert();
}
}
});
Here’s the code I used to get the location
import android.app.AlertDialog;
import android.app.Service;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.provider.Settings;
public class GPSTracker extends Service implements LocationListener {
private final Context context;
Flags for network/gps status
boolean isGPSEnabled = false;
boolean isNetworkEnabled = false;
boolean canGetLocation = false;
Location location;
double latitude;
double longitude;
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10;
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1;
public LocationManager locationManager;
public GPSTracker(Context context) {
this.context = context;
getLocation();
}
public Location getLocation(){
try {
locationManager = (LocationManager) context.getSystemService(LOCATION_SERVICE);
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (!isGPSEnabled && !isNetworkEnabled) {
} else {
this.canGetLocation = true;
For use over networks
if (isNetworkEnabled) {
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
if (locationManager != null) {
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if (location != null) {
latitude = location.getLatitude();
longitude = location.getLongitude();
}
}
}
For use over GPS
if (isGPSEnabled) {
if(location == null) {
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
MIN_TIME_BW_UPDATES,
MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
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();
} else {
getLocation();
}
return latitude;
}
public double getLongitude() {
if (location != null){
longitude = location.getLongitude();
} else {
getLocation();
}
return longitude;
}
public void showSettingsAlert() {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(context);
alertDialog.setTitle("GPS is being set");
alertDialog.setMessage("GPS is not enabled. Go to settings.");
alertDialog.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
context.startActivity(intent);
}
});
alertDialog.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
alertDialog.show();
}
public boolean canGetLocation() {
return this.canGetLocation;
}
I’ve also included the necessary code in the list:
<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" />
Thank you very much for the help
Solution
Do not use GPSTracker!!!! Dear God, this code will not die. This is terrible, bad, horrible code. I >http://gabesechansoftware.com/location-tracking/ There is a blog post showing more than a dozen different ways the code is flawed. I have a better implementation. The code was written by someone who didn’t fully understand location tracking and made a lot of false assumptions.
If I were allowed to remove a class from this site, it would be all the mentioned classes. It’s just very naïve code.