I'm trying to get a user's location and I have this method
public Location getCurrentLocation() {
LocationManager locManager = (LocationManager) getSystemService(LOCATION_SERVICE);
Criteria criteria = new Criteria();
String provider = locManager.getBestProvider(criteria, true);
Location location = locManager.getLastKnownLocation(provider);
return location;
}
I have another method that will center a circle object based on the location variable's latitude and longitude in this method
private void loadMapResources() {
userLocation = getCurrentLocation();
//DRAW CIRCLE HERE
if(userRadius != 0){
Circle radiusCircle = googleMap.addCircle(new CircleOptions()
.center(new LatLng(userLocation.getLatitude(), userLocation.getLongitude()))
.radius(userRadius)
.strokeWidth(4)
.strokeColor(Color.parseColor("#FF6699"))
.fillColor(Color.parseColor("#66F3F3F3"))
);
//SHOW USER ICON AT CURRENT LOCATION
BitmapDescriptor userIcon = BitmapDescriptorFactory.fromResource(R.drawable.ic_user);
googleMap.addMarker(new MarkerOptions()
.title("YOU ARE HERE")
.icon(userIcon)
.position(new LatLng(userLocation.getLatitude(), userLocation.getLongitude()))
);
}
}
Now this code has worked before on devices with and without GPS. Could anyone tell me why userLocation is throwing a NullPointerException?
Please keep in mind, that getLastKnownLocation can sometimes return null (for example, if provider is currently disabled or there is no last known location), so you should always check the result of this method:
Location location = locManager.getLastKnownLocation(provider);
if (location == null){
//handle this case
//return location with some default coordinates, for example
}
return location;
Related
I am trying to show current location on google map on andorid.I have written some cod to do that.But when i launch the app on Map Activity it does not show current location on google map.But when i tap on current location button on google map then it shows the current location.Please why it does not show current location automatically?
mMap.setMyLocationEnabled(true);
mMap.getUiSettings().setMyLocationButtonEnabled(true);
Log.i("MAP", "AFTER LOCATION");
LocationManager locationManager = (LocationManager) getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String bestProvider = locationManager.getBestProvider(criteria, true);
Location location = locationManager.getLastKnownLocation(bestProvider);
if (location != null) {
onLocationChanged(location);
}
locationManager.requestLocationUpdates(bestProvider,0, 0, this);
Use this function, when map is ready:
private void centerMap(GoogleMap map, Double latitude, Double longitude){
LatLng latLng = new LatLng(latitude, longitude);
CameraPosition cp = new CameraPosition.Builder()
.target(latLng)
.zoom(13)
.build();
map.animateCamera(CameraUpdateFactory.newCameraPosition(cp));
}
You can get coordinates from location like this: location.getLatitude() and Location.getLongitude()
Im facing some problem with my application, specifically with route plot/draw on my google maps. Ive made test route around my house and found out, that GPS providers are not as accurate as similar applications like runtastic or endomondo.
Sometimes Location listener makes incomprehensible changes on my map and the polyline then draws any lines on the map near my location even with perfect GPS signal.
Some other time, it just doesnot work. It does not listen to location change.
Can anybody explain me (like Im five) how does other fitness application get their current position and the plot route onto the google map? Thanks!
//Map Fragment
map = ((MapFragment) getFragmentManager().findFragmentById(R.id.fragment1)).getMap();
map.setMyLocationEnabled(true);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
Criteria criteria = new Criteria();
String provider = locationManager.getBestProvider(criteria, true);
//Permission gain
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) {
ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.ACCESS_COARSE_LOCATION},
MY_PERMISSION_ACCESS_COURSE_LOCATION);
return;
}
isLocationEnabled(getApplicationContext());
Location myLocation = locationManager.getLastKnownLocation(provider);
if (myLocation != null) {
latitude = myLocation.getLatitude();
longitude = myLocation.getLongitude();
float zoom = (float) 17.0;
map.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(latitude, longitude), zoom));
Log.e("TAG", "GPS is on");
Toast.makeText(MainActivity.this, "latitude:" + latitude + " longitude:" + longitude, Toast.LENGTH_SHORT).show();
} else {
locationManager.requestLocationUpdates(provider, 5000, 0, this);
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 5000, 10, this);
}
public void onLocationChanged(Location mylocation) {
if (lastLocationloc == null) {
lastLocationloc = mylocation;
}
LatLng lastLatLng = locationToLatLng(lastLocationloc);
LatLng thisLatLng = locationToLatLng(mylocation);
map.addPolyline(new PolylineOptions().add(lastLatLng).add(thisLatLng).width(6).color(Color.RED));
lastLocationloc = mylocation;
Toast.makeText(MainActivity.this, "!!!!Location CHANGE!!!!", Toast.LENGTH_SHORT).show();
}
public static LatLng locationToLatLng(Location loc) {
if (loc != null)
return new LatLng(loc.getLatitude(), loc.getLongitude());
return null;
}
For example, I want to plot it like this:
But my application works its own way..
First of all, you need to take into account the accuracy of the received location. You can get the accuracy using the Location.getAccuracy() method (documentation). The accuracy is measured in meters, so the lower the better:
if (location.getAccuracy() < MINIMUM_ACCURACY) {
// Add the new location to your polyline
}
You can set your MINIMUM_ACCURACY to be 10 meter for example.
On the other hand, you may want to add a new location to your polyline only if your new location is farther than a given distance to your last added location. As an example:
private static final float MINIMUM_ACCURACY = 10;
private static final float MINIMUM_DISTANCE_BETWEEN_POINTS = 20;
private Location lastLocationloc;
// ...
public void onLocationChanged(Location mylocation) {
if (mylocation.getAccuracy() < MINIMUM_ACCURACY) {
if (lastLocationloc == null || lastLocationloc.distanceTo(mylocation) > MINIMUM_DISTANCE_BETWEEN_POINTS) {
// Add the new location to your polyline
lastLocationloc = mylocation;
}
}
}
I have implemented the Google Maps API v2 in my Android app. I add a marker and zoom to level 14 when I open the activity containing the map fragment.
Here is how I add/update the marker:
private void updateMarker() {
if(marker != null){
marker.remove();
}
LatLng latlng = new LatLng(Double.parseDouble(latitude), Double.parseDouble(longitude));
marker = mMap.addMarker(new MarkerOptions().position(latlng).title(username));
marker.setIcon((BitmapDescriptorFactory.fromResource(R.drawable.marker)));
mMap.moveCamera(CameraUpdateFactory.newLatLng(latlng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(zoom), 2000, null);
}
It works correctly in debug via Android Studio, using a Nexus 5 with the latest Android installed. The problem is when I run a release build. The marker is added in the correct place, the zoom animation works correctly, zooming to the correct level. But it doesn't move to the marker I added.
Use this
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latlng, zoom));
Or
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latlng, zoom), 2000, null);
Don't call both method right after each other.
you should pass the result value of CameraUpdateFactory.newLatLngZoom(latlng, zoom) to animateCamera which returns a CameraUpdate that moves the center of the screen to a latitude and longitude specified by a LatLng object, and moves to the given zoom level. You can read more about it here
Implement GoogleApiClient.ConnectionCallbacks and override onConnected method as follows:
#Override
public void onConnected(Bundle bundle) {
Toast.makeText(this, "onConnected", Toast.LENGTH_SHORT).show();
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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;
}
mGMLastKnownLocation = LocationServices.FusedLocationApi.getLastLocation(mGMGoogleApiClient);
try {
// Get LocationManager object from System Service LOCATION_SERVICE
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// getting GPS status
isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
// getting network status
isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
if (isGPSEnabled)
{
Criteria criteria = new Criteria();
String provider = locationManager.getBestProvider(criteria, true);
//You can still do this if you like, you might get lucky
mGMLastKnownLocation = locationManager.getLastKnownLocation(provider);
if (mGMLastKnownLocation != null) {
//place marker at current position
mMap.clear();
// Get latitude of the current location
double latitude = mGMLastKnownLocation.getLatitude();
// Get longitude of the current location
double longitude = mGMLastKnownLocation.getLongitude();
// Create a LatLng object for the current location
latLng = new LatLng(latitude, longitude);
// Show the current location in Google Map
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
// Zoom in the Google Map
mMap.animateCamera(CameraUpdateFactory.zoomTo(7));
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(new LatLng(latitude, longitude)).title("You are here!").snippet("Consider yourself located").icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_ORANGE));
mCurrLocation = mMap.addMarker(markerOptions);
} else {
mGMLocationRequest = new LocationRequest();
mGMLocationRequest.setInterval(5000); //5 seconds
mGMLocationRequest.setFastestInterval(3000); //3 seconds
mGMLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);
LocationServices.FusedLocationApi.requestLocationUpdates(mGMGoogleApiClient, mGMLocationRequest, this);
}
} else {
//prompt user to enable location
if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
Intent i = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(i);
}
}
} catch (Exception e) {
Log.e("Error : Location", "Impossible to connect to LocationManager", e);
}
}
Also, implement LocationListener and override the onLocationChanged method as follows:
#Override
public void onLocationChanged(Location location) {
//remove previous current location marker and add new one at current position
if (mCurrLocation != null) {
mCurrLocation.remove();
}
double latitude = location.getLatitude();
double longitude = location.getLongitude();
latLng = new LatLng(latitude, longitude);
mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
mMap.animateCamera(CameraUpdateFactory.zoomTo(14));
MarkerOptions markerOptions = new MarkerOptions();
markerOptions.position(new LatLng(latitude, longitude)).title("Position").snippet("I am here").icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_ORANGE));
mCurrLocation = mMap.addMarker(markerOptions);
Toast.makeText(this, "Location Changed", Toast.LENGTH_SHORT).show();
//If you only need one location, unregister the listener
LocationServices.FusedLocationApi.removeLocationUpdates(mGMGoogleApiClient, this);
}
I hope it helps!!
I am creating an android app having google maps.I want to show the current location as the default blue dot with the current location button.The blue dot and the button is shown fine on a newer version of android.But on a older device ,it is not shown on the first running of the app but is fine from the second attempt.I have tried using android support library but to no avail.
The code i have used is shown below:
public void getcurrentlocation()
{
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
// Creating a criteria object to retrieve provider
Criteria criteria = new Criteria();
// Getting the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
Location location = locationManager.getLastKnownLocation(provider);
if(location!=null)
{
current_latitude = location.getLatitude();
current_longitude = location.getLongitude();
initialiseMap();
}
locationManager.requestLocationUpdates(provider, 20000, 0, this);
}
public void initialiseMap()
{
if (googleMap == null) {
googleMap = ( (SupportMapFragment) getSupportFragmentManager().findFragmentById(
R.id.map)).getMap();
}
// check if map is created successfully or not
if (googleMap == null) {
Toast.makeText(getApplicationContext(),
"Sorry! unable to create maps", Toast.LENGTH_SHORT)
.show();
}
else
{
googleMap.setMyLocationEnabled(true);
googleMap.getUiSettings().setMyLocationButtonEnabled(true);
googleMap.getUiSettings().setCompassEnabled(true);
// UiSettings uiSettings = googleMap.getUiSettings();
// uiSettings.setMyLocationButtonEnabled(true);
}
//locationManager.requestLocationUpdates(provider, 20000, 0, this);
LatLng latLng = new LatLng(current_latitude, current_longitude);
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
// Zoom in the Google Map
//googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 12f));
new RetrieveStoreDetails().execute();
}
Is there a workaround to show the blue dot from the beginning itself on the older version(2.6) of android.Please help!!
Blue dot appearance depends on your device being able to localize itself.
Make sure you turn on the GPS and have related settings enabled in My location part of Settings app: "Use wireless networks" and "Use GPS satellites".
i have this code:
if (item.getItemId() == R.id.tempMap) {
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Location location = null;
if(locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)||locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)){
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
provider = locationManager.getBestProvider(criteria, true);
location = locationManager.getLastKnownLocation(provider);
locationManager.requestLocationUpdates(provider, 20000, 1, this);
if (location != null) {
Log.e("PROVIDER SCELTO", provider);
onLocationChanged(location);
Log.e("LATITUDE", String.valueOf(latitude));
Log.e("LONGITUDE", String.valueOf(longitude));
and:
public void onLocationChanged(Location location) {
// TODO Auto-generated method stub
latitude = location.getLatitude();
longitude = location.getLongitude();
}
but the last gps point that it return is the last point after i use the "google maps navigator". So, if i not use gm navigator, the latitude and longitude is not updated.
WHY???
Thank you
location fix requires time wait till a good fix is recived this checks the time of the fix and sets location only if the fix is within a time period if you dont check the time of the fix it will provide the last fix recived irespective of when
public void onLocationChanged(Location location) {
Date dd=new Date(location.getTime());
Date ddd=new Date(System.currentTimeMillis()-(1000*60*15));
Log.e("", String.valueOf(location.getTime()+":"+System.currentTimeMillis()+":"+dd+":"+ddd));
if (dd.compareTo(ddd)==1?true:false) {
got=true;
latitude=String.valueOf(location.getLatitude());
longitude=String.valueOf(location.getLongitude());}
}