getLastKnownLocation always return null value. I have enabled geo fix and gps on emulator. However, there is no gps signal on the notification bar when running this on emulator. May I know is there any mistake in my code? Thanks.
public void onCreate(Bundle savedInstanceState) {
LocationManager location = null;
super.onCreate(savedInstanceState);
setContentView(R.layout.near_layout);
location = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.NO_REQUIREMENT);
criteria.setPowerRequirement(Criteria.NO_REQUIREMENT);
String bestProvider = location.getBestProvider(criteria, true);
LocationListener ll = new mylocationlistener();
Location loc = location.getLastKnownLocation(bestProvider);
if(loc != null)
{
double latitude = loc.getLatitude();
double longitude = loc.getLongitude();
Toast.makeText(nearPlace.this, " nice" + latitude, Toast.LENGTH_LONG).show();
}else{
Toast.makeText(nearPlace.this, "Location not available. GPS is not enabled.", Toast.LENGTH_LONG).show();
}
location.requestLocationUpdates(bestProvider, 0, 0, ll);
}
private class mylocationlistener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
Toast.makeText(nearPlace.this, " nice" + location.getLatitude(), Toast.LENGTH_LONG).show();
nearPlaceDownloaderTask getNearPlace = new nearPlaceDownloaderTask();
getNearPlace.execute(ANDROID_WEB_LINK + "gt.php?la=" + location.getLatitude() + "&lo=" + location.getLongitude());
}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
}
The reason your code is not working, is because you have specified the following criteria:
criteria.setAccuracy(Criteria.NO_REQUIREMENT);
Android will prefer to use network location over GPS, because you don't care about the accuracy. By specifying an accuracy of 20 meters or so, it will probably automatically invoke GPS.
To manually invoke GPS location updates, override bestProvider:
bestProvider = LocationManager.GPS_PROVIDER;
You can really simplify this into two lines of code:
LocationManager locationManager =
(LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, interval,
precision, listener);
Don't forget to unregister your listener:
locationManager.removeUpdates(listener);
You might also want to check this out geofix not working
Also make sure you have mock locations allowed set in the emulator. Take a look at Pauls answer as well, which is why I was asking in comments what provider was returned
Related
I want to get my current latitude and longitude using Mobile network provider, not GPS. AKA it should work without GPS with just your sim card. i have found many tutorials online claiming they find location with gps or network. however, they all seem to use GPS only! here or here and also here i don't want last knows location, as i don't wish to use GPS
Try This Code you can get current location without opening GPS
btnNWShowLocation.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
Location nwLocation = appLocationService
.getLocation(LocationManager.NETWORK_PROVIDER);
if (nwLocation != null) {
double latitude = nwLocation.getLatitude();
double longitude = nwLocation.getLongitude();
Toast.makeText(
getApplicationContext(),
"Mobile Location (NW): \nLatitude: " + latitude
+ "\nLongitude: " + longitude,
Toast.LENGTH_LONG).show();
} else {
showSettingsAlert("NETWORK");
}
}
});
Do it via Location Manager.
LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
// Define a listener that responds to location updates
LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
// Called when a new location is found by the network location provider.
makeUseOfNewLocation(location);
}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
public void onProviderDisabled(String provider) {}
};
// Register the listener with the Location Manager to receive location updates
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
I am trying to get latitude and longitude but sometime network is available but I am not getting value of latitude and longitude. I am using MyLocationListener class and put condition all but some time value is not getting.
protected void showCurrentLocation()
{
Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (location != null)
{
counter++;
latitude=location.getLatitude();
longitude=location.getLongitude();
altitude=location.getAltitude();
}
}
private class MyLocationListener implements LocationListener
{
#Override
public void onLocationChanged(Location location)
{
counter++;
latitude=location.getLatitude();
longitude=location.getLongitude();
altitude=location.getAltitude();
}
#Override
public void onStatusChanged(String s, int i, Bundle b)
{
}
#Override
public void onProviderDisabled(String s)
{
}
#Override
public void onProviderEnabled(String s)
{
}
}
Here Best way to get Longitude Latitude:
/** PROCESS for Get Longitude and Latitude **/
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
// Define a listener that responds to location updates
LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
// Called when a new location is found by the network location provider.
longitude = String.valueOf(location.getLongitude());
latitude = String.valueOf(location.getLatitude());
Log.d("msg", "changed Loc : "+longitude + ":"+latitude);
}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
public void onProviderDisabled(String provider) {}
};
// getting GPS status
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
// check if GPS enabled
if(isGPSEnabled){
Location location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(location != null)
{
longitude = String.valueOf(location.getLongitude());
latitude = String.valueOf(location.getLatitude());
Log.d("msg", "Loc : "+longitude + ":"+latitude);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);
}else
{
/*
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setCostAllowed(true);
String provider = locationManager.getBestProvider(criteria, true);
*/
location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
if(location != null)
{
longitude = String.valueOf(location.getLongitude());
latitude = String.valueOf(location.getLatitude());
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
}else
{
longitude = "0.00";
latitude = "0.00";
}
}
}
if device is not able to get currentLocation using GPS then it'll be take fron NetworkProvider or else it'll take 0,0 as my requirement but you can modify as per your requirement
May it'll helpful to you.
Happy Coding :D
See, this is a very common problem. In order to have exact Latitude and Longitude ,You must use GPS also it must me activated on the mobile device but GPS too have some limitations. GPS works most efficiently under open sky. you will not have a clear range inside a building. So try your code under open sky and check the response.
I have a simple class GPSListener which gets the GPS coordinates:
public class GPSListener implements LocationListener {
public static double latitude;
public static double longitude;
#Override
public void onLocationChanged(Location loc)
{
loc.getLatitude();
loc.getLongitude();
latitude = loc.getLatitude();
longitude = loc.getLongitude();
Log.d("GPSLISTENER ", "lat: "+latitude+" long:"+longitude);
} ...
Then trying to make use of this class in my activity, I simply invoke the class in my onCreate() function in my activity:
LocationManager mlocManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListener = new GPSListener();
Criteria criteria = new Criteria();
String bestProvider = mlocManager.getBestProvider(criteria, false);
mlocManager.requestLocationUpdates(bestProvider, 0, 0, mlocListener);
mlocManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 0, 0, mlocListener);
if (mlocManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
lat = GPSListener.latitude;
lon = GPSListener.longitude;
Log.d("GPS", "lat: "+lat+" long:"+lon);
} else {
// TODO: GPS not enabled
Log.d("GPSERROR", "GPS not enabled");
}
But whenever I run the application, lat and lon in my activity are always zero. I'm not quite sure how to get around this issue.
When logging:
Log.d("GPSLISTENER ", "lat: "+latitude+" long:"+longitude);
It returns the correct latitude and longitude, it just takes a second or two after the activity starts.
Log.d("GPSSUCCESS", "lat: "+lat+" long:"+lon);
Just returns 0.0 for both. I was under the impression that .requestLocationUpdates would pass the value to lat and lon before the if statement is executed. How can I accomplish this?
You are using public static field for latitude, longitude.
Please change it to non static and using setter, getter with instant object:
lat = mlocListener.getLatitude();
lon = mlocListener.getLongitude();
Google updated its location handling logic. It is now easier to listen location updates with fused location provider. You can implement your location listener in 5 min. Take a look.
Methods for getting the most accurate location
You are listening only gps provider and it is not ready(on waiting for location status) yet and then it does not return any location. Just take a look at fused location provider and write your location listener again.
try this...
mGoogleMap.setOnMyLocationButtonClickListener(new OnMyLocationButtonClickListener() {
#Override
public boolean onMyLocationButtonClick()
{
try
{
Location myLocation = mGoogleMap.getMyLocation();
onLocationChanged(myLocation);
}
catch (Exception e)
{
Log.getStackTraceString(e);
}
return false;
}
});
user this Handler to get Location
private Handler customHandler = new Handler();
private Runnable updateTimerThread = new Runnable() {
#Override
public void run()
{
try
{
Location myLocation = mGoogleMap.getMyLocation();
secndLocationListener.onLocationChanged(myLocation);
}
catch (Exception e)
{
Log.getStackTraceString(e);
}
}
};
to run this
customHandler.postDelayed(updateTimerThread , 1000);
LocationManager uses the last known location from the cache. The cache is updated when you load google maps. Try this out, go out in the open and check your location. Move to a different location about 200m and check your location again. It will be same as the old one. Now, load google maps, you will notice that you application magically now has the new location.
You need to programmatically kick that cache to the latest location. The only way to do that is
YOUR_APPLICATION_CONTEXT.getLocationManager().requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 0, 0, new LocationListener() {
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
#Override
public void onLocationChanged(final Location location) {
}
});
I am new to android, can anyone help me for my question....
How to get a current position and tracking in map using GPS without giving any location in a program?????
You want the easy way out ! Use MyLocationOverlay object. you can get the current location by calling the method getLastFix(); . To enable tracking use enableMyLocation(). To add this object to the map you need to add it to your map overlays.
MyLocationOverlay currLoc=new MyLocationOverlay(context,mapKey);
mapView.getAllOverlays.add(currLoc);
currLoc.enableMyLocation();
Location myLastLocation=currLoc.getLastFix();
currLoc.enableCompass();
Do make sure, in onPause() you do this :
currLoc.disableMyLocation(); //to save battery.
you can resume updates in onResume() by calling currLoc.enableMyLocation();
This is the easiest way I could find! and it is quite accurate too
Try ;
String m_BestProvider;
LocationManager m_LocationManager;
LocationListener m_LocationListener = null;
Location m_Location = null;
m_LocationManager = (LocationManager) m_Context.getSystemService(Context.LOCATION_SERVICE);
Criteria c = new Criteria();
c.setAccuracy(Criteria.ACCURACY_COARSE);
c.setAltitudeRequired(false);
c.setBearingRequired(false);
c.setSpeedRequired(false);
c.setCostAllowed(true);
c.setPowerRequirement(Criteria.POWER_HIGH);
m_BestProvider = m_LocationManager.getBestProvider(c, false);
// Define a listener that responds to location updates
m_LocationListener = new LocationListener() {
public void onLocationChanged(Location location) {
// Called when a new location is found by the network location provider.
}
public void onStatusChanged(String provider, int status, Bundle extras) {}
public void onProviderEnabled(String provider) {}
public void onProviderDisabled(String provider) {}
};
m_LocationManager.requestLocationUpdates(m_BestProvider, 0, 0, m_LocationListener);
m_Location = m_LocationManager.getLastKnownLocation(m_BestProvider);
Systme.out.println(m_Location.getLatitude() "," +m_Location.getLongitude());
Add in AndriodManifest.xml:
<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"/>
public class GPSLocationBased extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.locationbased);
LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationListener ll = new Mylocationlistener();
// ---Get the status of GPS---
boolean isGPS = lm.isProviderEnabled(LocationManager.GPS_PROVIDER);
// If GPS is not enable then it will be on
if(!isGPS)
{
Intent intent = new Intent("android.location.GPS_ENABLED_CHANGE");
intent.putExtra("enabled", true);
sendBroadcast(intent);
}
//<--registers the current activity to be notified periodically by the named provider. Periodically,
//the supplied LocationListener will be called with the current Location or with status updates.-->
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, ll);
}
/**
*Mylocationlistener class will give the current GPS location
*with the help of Location Listener interface
*/
private class Mylocationlistener implements LocationListener {
#Override
public void onLocationChanged(Location location) {
if (location != null) {
// ---Get current location latitude, longitude, altitude & speed ---
Log.d("LOCATION CHANGED", location.getLatitude() + "");
Log.d("LOCATION CHANGED", location.getLongitude() + "");
float speed = location.getSpeed();
double altitude = location.getAltitude();
Toast.makeText(GPSLocationBased.this,"Latitude = "+
location.getLatitude() + "" +"Longitude = "+ location.getLongitude()+"Altitude = "+altitude+"Speed = "+speed,
Toast.LENGTH_LONG).show();
}
}
#Override
public void onProviderDisabled(String provider) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}
}
Through this code u will get ur lat and long.
and u may use it on ur gmap.
this code also start gps functionality problematically. Hope this will help u.. All the best :)
I have asked this before and i have had a couple answers but no solution. could someone please help me understand what i need to do to fix this problem? My app force closes unless GPS in enabled BEFORE the app is started. I am learning how to program android and some answers I get I just dont not understand. Im hoping someone will point out which piece of code is causing the problem and what i need to do to fix it. If more information is needed, please let me know what you need. and seriously, thanks for helping and having patience with this 'beginner.'
public class GlenrochieMain extends Activity
{
//called when activity is first created
#Override
protected void onCreate(Bundle savedInstanceState) {
// shows main layout
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//GPS Functionality
LocationManager locationManager;
String context = Context.LOCATION_SERVICE;
locationManager = (LocationManager)getSystemService(context);
//Criteria for GPS
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);
String provider = locationManager.getBestProvider(criteria, true);
Location location = locationManager.getLastKnownLocation(provider);
updateWithNewLocation(location);
//updates location every 5second+5meters
locationManager.requestLocationUpdates(provider, 5000, 5,
locationListener);
}
private final LocationListener locationListener = new LocationListener() {
public void onLocationChanged(Location location) {
updateWithNewLocation(location);
}
public void onProviderDisabled(String provider){
updateWithNewLocation(null);
}
public void onProviderEnabled(String provider){ }
public void onStatusChanged(String provider, int status,
Bundle extras){ }
};
private void updateWithNewLocation(Location location) {
String latLongString;
TextView myLocationText;
myLocationText = (TextView)findViewById(R.id.myLocationText);
if (location != null) {
double lat = location.getLatitude();
double lng = location.getLongitude();
latLongString = "Lat:" + lat + "\nLong:" + lng;
} else {
latLongString = "No location found";
}
myLocationText.setText("Your Current Position is:\n" +
latLongString);
}
}
You have to catch exception for non-operational GPS. Performing Exception catching is very important for stability for most programming languages.
My suggetion would be to check if your GPS service is enabled, if so then call the requestLocationUpdates. Sample code is below:
final LocationManager manager = (LocationManager) getSystemService( Context.LOCATION_SERVICE );
if ( !manager.isProviderEnabled( LocationManager.GPS_PROVIDER ) ) {
// request updates here..
}
Secondly, you are looking for "Criteria.ACCURACY_FINE", so only GPS can provide this. You can replace the provider as "LocationManager.GPS_PROVIDER"
Also, note that GPS is not Low Power.