Location change glitches on map using polyline options - java

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;
}
}
}

Related

How can I get greater than 1m position accuracy with android FusedLocationProviderClient?

I'm trying to create an android app that gives accurate location (1m or less) indoors. It seems the recommended way is to use the
a FusedLocationProviderClient
However the current horizontal accuracy I'm getting is between 5m and 15m for longitude and latitude while the vertical accuracy is often up to 50m out.
Not sure if it makes a difference but the the test device is an HTC U11?
I've updated google play service location com.google.android.gms:play-services-location:17.0.0
I've included android.permission.ACCESS_FINE_LOCATION in my app manifest and locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY); in the location request.
I've got some code in there which turns the GPS on.
mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(3 * 1000); // 3 seconds
locationRequest.setFastestInterval(1 * 1000); // 3 seconds
new GpsUtils(this).turnGPSOn(new GpsUtils.onGpsListener() {
#Override
public void gpsStatus(boolean isGPSEnable) {
// turn on GPS
isGPS = isGPSEnable;
}
});
locationCallback = new LocationCallback() {
#Override
public void onLocationResult(LocationResult locationResult) {
if (locationResult == null) {
return;
}
for (Location location : locationResult.getLocations()) {
if (location != null) {
wayLatitude = location.getLatitude();
wayLongitude = location.getLongitude();
Lat.setText(Double.toString(location.getLatitude()));
Longs.setText(Double.toString(location.getLongitude()));
Acc.setText(String.format("%.2f", location.getAccuracy()));
if(location.hasAltitude()) {
Alt.setText(String.format("%.2f",location.getAltitude() - 108));
VAcc.setText(String.format("%.2f",location.getVerticalAccuracyMeters()));
}
else {
Alt.setText("Lost");
VAcc.setText("Lost");
}
SendToBackend(wayLatitude,wayLongitude, location);
if (!isContinue && mFusedLocationClient != null) {
mFusedLocationClient.removeLocationUpdates(locationCallback);
}
}
}
}
};
According to google it should be possible to get below 1m accuracy indoors. a link.
Thanks in advance :-)

Adding Default Location if User Doesn't Allow Permission for a Fine Location for a Map in Android

I am starting to learn about the runtime permissions. I have a map and I made a permission. If user allows fine location - map zooms to his current location, and if he doesn't allow it, the map stays in the place. What I want to do instead of map staying in the place is this: if the user doesn't allow permission for accessing his location, map should zoom in to my custom location (Greenwich).
My maps fragment:
mapView.getMapAsync(new OnMapReadyCallback() {
#Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
if (ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(getActivity(), Manifest.permission.ACCESS_FINE_LOCATION)) {
} else {
ActivityCompat.requestPermissions(getActivity(), new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, MY_LOCATION_REQUEST_CODE);
}
return;
}
mMap.setMyLocationEnabled(true);
LocationManager locationManager = (LocationManager) getActivity().getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
// if (ContextCompat.checkSelfPermission(getContext(), Manifest.permission.ACCESS_FINE_LOCATION)
// == PackageManager.PERMISSION_GRANTED) {
// mMap.setMyLocationEnabled(true);
// } else {
// // Show rationale and request permission.
// }
//Disable Map Toolbar:
mMap.getUiSettings().setMapToolbarEnabled(false);
// Get the name of the best provider and current location
String provider = null;
if (locationManager != null) {
provider = locationManager.getBestProvider(criteria, true);
}
// Get current location
Location myLocation = null;
if (locationManager != null) {
myLocation = locationManager.getLastKnownLocation(provider);
}
// Set default latitude and longitude to Greenwich
double latitude = 51.4825766;
double longitude = -0.0076589;
// Get latitude and longitude of the current location and a LatLng object
if (myLocation != null) {
latitude = myLocation.getLatitude();
longitude = myLocation.getLongitude();
}
CameraPosition cameraPosition = new CameraPosition.Builder()
.target(new LatLng(latitude, longitude)).zoom(14).build();
mMap.animateCamera(CameraUpdateFactory
.newCameraPosition(cameraPosition));
}
You can zoom to location manually with this code :
CameraUpdate center=CameraUpdateFactory.newLatLng(new LatLng(latitude,
longitude));
CameraUpdate zoom=CameraUpdateFactory.zoomTo(15);
map.moveCamera(center);
map.animateCamera(zoom);
Couldn't find solution so I put the permission inside the parent activity. I think it is a known bug.

Why is google maps not zooming on the Lat/Long I provide?

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!!

Location value returning null android

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;

android LocationManager last position

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());}
}

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