I'm trying an application that displays the latitude and longitude positions. I tried giving lat. & lon. values using geo fix and even emulator control but I'm not getting the output. Can anyone help me out?
Here's the code and output that i get:
public class LocationTest extends Activity
{
private LocationManager mgr;
private TextView output;
private String best;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mgr = (LocationManager) getSystemService(LOCATION_SERVICE);
output = (TextView) findViewById(R.id.output);
StringBuilder sb = new StringBuilder("Enabled Provider:");
Criteria criteria = new Criteria();
String provider = mgr.getBestProvider(criteria, true);
mgr.requestLocationUpdates(provider, 1000, 0,
new LocationListener()
{
public void onLocationChanged(Location location) {}
public void onProviderDisabled(String provider) {}
public void onProviderEnabled(String provider) {}
public void onStatusChanged(String provider, int status, Bundle extras) {}
});
sb.append("\n").append(provider).append(":");
Location location = mgr.getLastKnownLocation(provider);
if (location != null)
{
double lat = location.getLatitude();
double lng = location.getLongitude();
sb.append(lat).append(",").append(lng);
}
else
{
sb.append("No Location");
}
output.setText(sb);
}
}
Output:
Enabled provider:
gps:No Location
You need to put code in public void onLocationChanged(Location location) {} of your LocationListener. This is where location changes are informed.
getLastKnownLocation() doesn't give you current location, but last known location (which will most likely be null on the emulator).
Use Android SDK's DDMS to signal GPS position. This will call onLocationChanged(). You need a way to preserve the new location in your class (for example adding a Location class object to your Activity).
Related
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) {
}
});
Good day,
at the moment I am creating an Android application that will show the user their current location on a map. Sadly I can't seem to zoom at the current location of the user in the OnCreate method. It seems to work in a OnMapClick method.
I would like to get rid of the OnMapClick method and show the current location of the user when the map is loaded.
the code below is part of the OnCreate method of the map class
Settings setting = new Settings();
setting.saveSettings(Maps.this);
LocationManager locationManager =(LocationManager) getSystemService(Context.LOCATION_SERVICE);
Here is the code of the OnLocationChanged method
public void onLocationChanged(Location location) {
int lat = (int)(location.getLatitude());
int lng =(int)(location.getLongitude());
LatLng loc = new LatLng(lat,lng);
myMap.moveCamera(CameraUpdateFactory.newLatLngZoom(loc, 15));
myMap.animateCamera(CameraUpdateFactory.zoomIn());
I posses an API key and have the map in my application.
This code may help you...
my listener
private LocationListener listener = 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(Location loc) {
// will get the location lat long
}
};
code to start the location manager update listener
LocationManager mLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (mLocationManager != null) {
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);
String prividerName = mLocationManager.getBestProvider(criteria, true);
if (prividerName != null) {
mLocationManager.requestLocationUpdates(prividerName, 30 * 1000, 0, listener);
Once you get the lat/long u can plot the location details as below
GoogleMap googleMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(
R.id.map)).getMap();
LatLng current = new LatLng(mUserLatitude, mUserLongitude);
googleMap.addMarker(new MarkerOptions().position(current).title("Current Location"))
.showInfoWindow();
googleMap.getUiSettings().setCompassEnabled(true);
googleMap.getUiSettings().setZoomControlsEnabled(true);
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(current, 10));
You probably do not have a fix on the location yet. I would suggest doing
myMap.setMyLocationEnabled(true);
myMap.setOnMyLocationChangeListener(this);
then in you onLocationChanged put a boolean for a first load or something so it does not go to the location every time the location changes and then do the camera movement in there
I hope this piece of code can help to clearify my question.
the code below is my LocationListener
private LocationListener listener = 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(Location loc) {
double lat = loc.getLatitude();
double lng = loc.getLongitude();
}
};
the latitude and longitude ares saved in antoher class,
the code below show my way of initialzing the map.
String locLat = ((Settings)this.getApplication()).getLat();
String locLng = ((Settings) this.getApplication()).getLng();
double DlocLat = Double.parseDouble(locLat);
double DlocLng = Double.parseDouble(locLng);
myMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map)).getMap();
LatLng current = new LatLng(DlocLat,DlocLng);
myMap.addMarker(new MarkerOptions().position(current).title("Current Location")).showInfoWindow();
myMap.setMyLocationEnabled(true);//show the location on the map
myMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);//show the regular google maps
myMap.animateCamera(CameraUpdateFactory.newLatLngZoom(current, 10));
This is my code. Please tell me y it is not able to calculate the distance.. In this code res is a long variable which is supposed to store the total distance covered. This code is supposed to calculate distance based on GPS as soon as there is a change in the latitude and longitude..
String serviceString = Context.LOCATION_SERVICE;
LocationManager locationManager;
locationManager= (LocationManager)getSystemService(serviceString);
String provider = LocationManager.GPS_PROVIDER;
final Location loc1=locationManager.getLastKnownLocation(provider);
//Location loc1=new Location("");
String netprovider=LocationManager.NETWORK_PROVIDER;
lat1=loc1.getLatitude();
lon1=loc1.getLongitude();
LocationListener myLocationListener = new LocationListener()
{
public void onLocationChanged(Location loc1)
{
Location loc2=new Location("");
lat2=loc2.getLatitude();
lon2=loc2.getLongitude();
dtvalue.setText(lat1+","+lon1+","+lat2+","+lon2);
Location.distanceBetween(lat1,lon1,lat2,lon2,dist);
res=res+(long)dist[0];
lat1=lat2;
lon1=lon2;
}
public void onProviderDisabled(String provider)
{
// Update application if provider disabled.
}
public void onProviderEnabled(String provider)
{
// Update application if provider enabled.
}
public void onStatusChanged(String provider, int status,
Bundle extras)
{
// Update application if provider hardware status changed.
}
};
locationManager.requestLocationUpdates(provider, 5000, 1, myLocationListener);
locationManager.requestLocationUpdates(netprovider, 5000, 1, myLocationListener);
The problem that you are defining an empty location Location loc2=new Location(""); and then using it.
You can define lat1 and lon1 in your class.
public void onLocationChanged(Location loc1)
{
if(lat1 != 0 && long1 != 0) {
Location.distanceBetween(lat1,lon1,loc1.getLatitude(),loc1.getLongitude(),dist);
res+=(long)dist[0];
}
lat1=loc1.getLatitude();
lon1=loc1.getLongitude();
}
I created this earlier on today, but it is not working. Location manager returns null, and I've even implemented the listener. Any ideas to the problems. thanks.
Edited:
I think this line is the problem
Location location = locationManager.getLastKnownLocation(provider);
Basically, if location is null, it will go into the else part of the if statement below it. Every time I compile the code, it will go into the else statement meaning it location is not updating.
public class Activity1 extends Activity implements LocationListener {
/** Called when the activity is first created. */
JoshTwoActivity main;
Activity2 two;
boolean checkTick = false;
String locationplace = "";
private LocationManager locationManager;
private String provider;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria, false);
System.out.println(provider);
System.out.println(locationManager.getProviders(criteria, false));
System.out.println(locationManager.getProvider("network"));
System.out.println(locationManager.getAllProviders());
Location location = locationManager.getLastKnownLocation(provider);
System.out.println(locationManager.isProviderEnabled(provider));
// Initialize the location fields
if (location != null) {
System.out.println("Provider " + provider + " has been selected.");
int lat = (int) (location.getLatitude());
int lng = (int) (location.getLongitude());
System.out.println(String.valueOf(lat));
System.out.println(String.valueOf(lng));
} else {
System.out.println("Provider not available");
System.out.println("Provider not available");
}
}
/* Request updates at startup */
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider, 400, 1, this);
}
/* Remove the locationlistener updates when Activity is paused */
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
public void onLocationChanged(Location location) {
int lat = (int) (location.getLatitude());
int lng = (int) (location.getLongitude());
System.out.println(String.valueOf(lat));
System.out.println(String.valueOf(lng));
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(this, "Enabled new provider " + provider,
Toast.LENGTH_SHORT).show();
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(this, "Disenabled provider " + provider,
Toast.LENGTH_SHORT).show();
}
}
getLastKnownLocation() returns a location with the last known location fix for a provider. If the provider returns null, the provider has never had a location fix. It doesn't mean the provider is not available.
Once you call getLastKnownLocation() you should check to see if the results are accurate or recent enough for your purpose. If not you should request location updates using requestLocationUpdates().
This blog post contains everything you need to know about writing code using location providers.
http://android-developers.blogspot.com/2011/06/deep-dive-into-location.html
Ok my first guess is that you are not giving location fix via command line or by using eclipse DDMS perpective. If this is problem go open DDMS perpecive and give latitude and longtiude you want and send it. So location will not be null from now on if this is the problem.
The following link may help you in understanding how to use emulator in finding the location. The last section of this page has that information.
http://developer.android.com/guide/topics/location/obtaining-user-location.html
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 :)