I recently added get location function. When I try to show longitude and latitude, it returns zero.
This my LocationListener class:
inner class MylocationListener: LocationListener {
constructor():super(){
mylocation= Location("me")
mylocation!!.longitude
mylocation!!.latitude
}
override fun onLocationChanged(location: Location?) {
mylocation=location
}
override fun onStatusChanged(p0: String?, p1: Int, p2: Bundle?) {}
override fun onProviderEnabled(p0: String?) {}
override fun onProviderDisabled(p0: String?) {}
}
And this my GetUserLocation function:
fun GetUserLocation(){
var mylocation= MylocationListener()
var locationManager=getSystemService(Context.LOCATION_SERVICE) as LocationManager
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,0,0.1f,mylocation)
}
And this my function to return my longitude and latitude:
fun getLoction (view: View){
prgDialog!!.show();
GetUserLocation()
button.setTextColor(getResources().getColor(R.color.green));
textView.text = mylocation!!.latitude.toFloat().toString()
Toast.makeText(this, mylocation!!.latitude.toFloat().toString(), Toast.LENGTH_LONG).show()
Toast.makeText(this, mylocation!!.longitude.toFloat().toString(), Toast.LENGTH_LONG).show()
prgDialog!!.hide()
}
In 2019 Best Offical Solution in Kotlin
Google API Client/FusedLocationApi are deprecated and Location Manager is not useful at all.
So Google prefer Fused Location Provider Using the Google Play services location APIs
"FusedLocationProviderClient" is used to get location and its better way for battery saving and accuracy
Here is sample code in kotlin to get the last known location /one-time location( equivalent to the current location)
// declare a global variable of FusedLocationProviderClient
private lateinit var fusedLocationClient: FusedLocationProviderClient
// in onCreate() initialize FusedLocationProviderClient
fusedLocationClient = LocationServices.getFusedLocationProviderClient(context!!)
/**
* call this method for receive location
* get location and give callback when successfully retrieve
* function itself check location permission before access related methods
*
*/
fun getLastKnownLocation() {
fusedLocationClient.lastLocation
.addOnSuccessListener { location->
if (location != null) {
// use your location object
// get latitude , longitude and other info from this
}
}
}
If your app can continuously track the location then you have to receive Receive location updates
Check the sample for that in kotlin
// declare a global variable FusedLocationProviderClient
private lateinit var fusedLocationClient: FusedLocationProviderClient
// in onCreate() initialize FusedLocationProviderClient
fusedLocationClient = LocationServices.getFusedLocationProviderClient(context!!)
// globally declare LocationRequest
private lateinit var locationRequest: LocationRequest
// globally declare LocationCallback
private lateinit var locationCallback: LocationCallback
/**
* call this method in onCreate
* onLocationResult call when location is changed
*/
private fun getLocationUpdates()
{
fusedLocationClient = LocationServices.getFusedLocationProviderClient(context!!)
locationRequest = LocationRequest()
locationRequest.interval = 50000
locationRequest.fastestInterval = 50000
locationRequest.smallestDisplacement = 170f // 170 m = 0.1 mile
locationRequest.priority = LocationRequest.PRIORITY_HIGH_ACCURACY //set according to your app function
locationCallback = object : LocationCallback() {
override fun onLocationResult(locationResult: LocationResult?) {
locationResult ?: return
if (locationResult.locations.isNotEmpty()) {
// get latest location
val location =
locationResult.lastLocation
// use your location object
// get latitude , longitude and other info from this
}
}
}
}
//start location updates
private fun startLocationUpdates() {
fusedLocationClient.requestLocationUpdates(
locationRequest,
locationCallback,
null /* Looper */
)
}
// stop location updates
private fun stopLocationUpdates() {
fusedLocationClient.removeLocationUpdates(locationCallback)
}
// stop receiving location update when activity not visible/foreground
override fun onPause() {
super.onPause()
stopLocationUpdates()
}
// start receiving location update when activity visible/foreground
override fun onResume() {
super.onResume()
startLocationUpdates()
}
Make sure you take care about Mainfaist permission and runtime permission for location
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
and for Gradle add this
implementation 'com.google.android.gms:play-services-location:17.0.0'
For more details follow these official documents
https://developer.android.com/training/location/retrieve-current
https://developer.android.com/training/location/receive-location-updates
https://developers.google.com/android/reference/com/google/android/gms/location/FusedLocationProviderClient
When GetUserLocation returns, locationManager goes out of scope and presumably is destroyed, preventing onLocationChanged from being called and providing updates.
Also, you've defined mylocation inside of GetUserLocation so it also goes out of scope and further kills any chance or your getting an update.
You have not shown where and how the outer mylocation is declared (outside of GetUserLocation), but how ever it is declared, it is being shadowed by the one inside of GetUserLocation. So you aren't getting much.
Here is an example of how you might do it. (The variable thetext is defined within the layout xml and accessed with Kotlin extensions.)
// in the android manifest
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
// allow these through Appliation Manager if necessary
// inside a basic activity
private var locationManager : LocationManager? = null
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
setSupportActionBar(toolbar)
// Create persistent LocationManager reference
locationManager = getSystemService(LOCATION_SERVICE) as LocationManager?
fab.setOnClickListener { view ->
try {
// Request location updates
locationManager?.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0L, 0f, locationListener)
} catch(ex: SecurityException) {
Log.d("myTag", "Security Exception, no location available")
}
}
}
//define the listener
private val locationListener: LocationListener = object : LocationListener {
override fun onLocationChanged(location: Location) {
thetext.text = ("" + location.longitude + ":" + location.latitude)
}
override fun onStatusChanged(provider: String, status: Int, extras: Bundle) {}
override fun onProviderEnabled(provider: String) {}
override fun onProviderDisabled(provider: String) {}
}
I know it's late, but now Google has made it simpler to use. In the developer site, it says that you need to create a Client:
private lateinit var fusedLocationClient: FusedLocationProviderClient
Then onCreate get the provider:
override fun onCreate(savedInstanceState: Bundle?) {
// ...
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this)
}
And finally, to get your last location just call:
//Don't forget to ask for permissions for ACCESS_COARSE_LOCATION
//and ACCESS_FINE_LOCATION
#SuppressLint("MissingPermission")
private fun obtieneLocalizacion(){
fusedLocationClient.lastLocation
.addOnSuccessListener { location: Location? ->
latitude = location?.latitude
longitude = location?.longitude
}
}
*Tested with this implementation for location (Setup in your app gradle file)
implementation 'com.google.android.gms:play-services-location:15.0.1'
For more info, check this link:
Obtain last location
Get location with address in android kotlin
Add this line in dependencies
implementation 'com.google.android.gms:play-services-location:17.0.0'
Add this in AndroidManifest
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
Copy this below code in your class
class MainActivity : AppCompatActivity() {
private lateinit var fusedLocationClient: FusedLocationProviderClient
private lateinit var locationRequest: LocationRequest
private lateinit var locationCallback: LocationCallback
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_splash)
/*Check location*/
checkLocation()
}
private fun checkLocation(){
val manager = getSystemService(Context.LOCATION_SERVICE) as LocationManager
if (!manager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
showAlertLocation()
}
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this)
getLocationUpdates()
}
private fun showAlertLocation() {
val dialog = AlertDialog.Builder(this)
dialog.setMessage("Your location settings is set to Off, Please enable location to use this application")
dialog.setPositiveButton("Settings") { _, _ ->
val myIntent = Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS)
startActivity(myIntent)
}
dialog.setNegativeButton("Cancel") { _, _ ->
finish()
}
dialog.setCancelable(false)
dialog.show()
}
private fun getLocationUpdates() {
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this)
locationRequest = LocationRequest()
locationRequest.interval = 50000
locationRequest.fastestInterval = 50000
locationRequest.smallestDisplacement = 170f //170 m = 0.1 mile
locationRequest.priority = LocationRequest.PRIORITY_HIGH_ACCURACY //according to your app
locationCallback = object : LocationCallback() {
override fun onLocationResult(locationResult: LocationResult?) {
locationResult ?: return
if (locationResult.locations.isNotEmpty()) {
/*val location = locationResult.lastLocation
Log.e("location", location.toString())*/
val addresses: List<Address>?
val geoCoder = Geocoder(applicationContext, Locale.getDefault())
addresses = geoCoder.getFromLocation(
locationResult.lastLocation.latitude,
locationResult.lastLocation.longitude,
1
)
if (addresses != null && addresses.isNotEmpty()) {
val address: String = addresses[0].getAddressLine(0)
val city: String = addresses[0].locality
val state: String = addresses[0].adminArea
val country: String = addresses[0].countryName
val postalCode: String = addresses[0].postalCode
val knownName: String = addresses[0].featureName
Log.e("location", "$address $city $state $postalCode $country $knownName")
}
}
}
}
}
// Start location updates
private fun startLocationUpdates() {
fusedLocationClient.requestLocationUpdates(
locationRequest,
locationCallback,
null /* Looper */
)
}
// Stop location updates
private fun stopLocationUpdates() {
fusedLocationClient.removeLocationUpdates(locationCallback)
}
// Stop receiving location update when activity not visible/foreground
override fun onPause() {
super.onPause()
stopLocationUpdates()
}
// Start receiving location update when activity visible/foreground
override fun onResume() {
super.onResume()
startLocationUpdates()
}}
Run your code and check the log, Happy Coding
I read many of answers but question is get only last known location.
With receiver it continuously send latitude and longitude
I have solution for this in kotlin..
Give permissions
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
public fun getLastKnownLocation(context: Context) {
val locationManager: LocationManager = context.getSystemService(Context.LOCATION_SERVICE) as LocationManager
val providers: List<String> = locationManager.getProviders(true)
var location: Location? = null
for (i in providers.size - 1 downTo 0) {
location= locationManager.getLastKnownLocation(providers[i])
if (location != null)
break
}
val gps = DoubleArray(2)
if (location != null) {
gps[0] = location.getLatitude()
gps[1] = location.getLongitude()
Log.e("gpsLat",gps[0].toString())
Log.e("gpsLong",gps[1].toString())
}
}
I would like to help someone who is trying to get location from scratch.
Here is the reference: Kotlin Get Current Location
Code will first check whether location is on or off in device and then will fetch latitude and longitudes and will update it constantly.
In build.gradle(Module:app) file put this
compile 'com.google.android.gms:play-services:11.8.0'
activity_main.xml code
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_marginTop="10dp"
android:layout_marginLeft="10dp"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<TextView
android:id="#+id/latitude"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="Latitude:"
android:textSize="18sp" />
<TextView
android:id="#+id/latitude_textview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/latitude"
android:layout_marginLeft="10dp"
android:layout_toRightOf="#+id/latitude"
android:textSize="16sp" />
<TextView
android:id="#+id/longitude"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:text="Longitude:"
android:layout_marginTop="24dp"
android:textSize="18sp" />
<TextView
android:id="#+id/longitude_textview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/longitude"
android:layout_marginLeft="10dp"
android:layout_toRightOf="#+id/longitude"
android:textSize="16sp"/>
</RelativeLayout>
MainActivity.kt
import android.Manifest
import android.annotation.SuppressLint
import android.content.Context
import android.content.Intent
import android.content.pm.PackageManager
import android.location.Location
import android.location.LocationManager
import android.provider.Settings
import android.support.v4.app.ActivityCompat
import android.support.v7.app.AlertDialog
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import android.widget.TextView
import android.widget.Toast
import com.google.android.gms.common.ConnectionResult
import com.google.android.gms.common.api.GoogleApiClient
import com.google.android.gms.location.LocationRequest
import com.google.android.gms.location.LocationServices
import com.google.android.gms.maps.model.LatLng
class MainActivity : AppCompatActivity(), GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, com.google.android.gms.location.LocationListener {
private var mLatitudeTextView: TextView? = null
private var mLongitudeTextView: TextView? = null
private var mGoogleApiClient: GoogleApiClient? = null
private var mLocation: Location? = null
private var mLocationManager: LocationManager? = null
private var mLocationRequest: LocationRequest? = null
private val listener: com.google.android.gms.location.LocationListener? = null
private val UPDATE_INTERVAL = (2 * 1000).toLong() /* 10 secs */
private val FASTEST_INTERVAL: Long = 2000 /* 2 sec */
private var locationManager: LocationManager? = null
private val isLocationEnabled: Boolean
get() {
locationManager = getSystemService(Context.LOCATION_SERVICE) as LocationManager
return locationManager!!.isProviderEnabled(LocationManager.GPS_PROVIDER) || locationManager!!.isProviderEnabled(LocationManager.NETWORK_PROVIDER)
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
mLatitudeTextView = findViewById(R.id.latitude_textview) as TextView
mLongitudeTextView = findViewById(R.id.longitude_textview) as TextView
mGoogleApiClient = GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build()
mLocationManager = this.getSystemService(Context.LOCATION_SERVICE) as LocationManager
Log.d("gggg","uooo");
checkLocation() //check whether location service is enable or not in your phone
}
#SuppressLint("MissingPermission")
override fun onConnected(p0: Bundle?) {
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
}
startLocationUpdates()
mLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient)
if (mLocation == null) {
startLocationUpdates()
}
if (mLocation != null) {
// mLatitudeTextView.setText(String.valueOf(mLocation.getLatitude()));
//mLongitudeTextView.setText(String.valueOf(mLocation.getLongitude()));
} else {
Toast.makeText(this, "Location not Detected", Toast.LENGTH_SHORT).show()
}
}
override fun onConnectionSuspended(i: Int) {
Log.i(TAG, "Connection Suspended")
mGoogleApiClient!!.connect()
}
override fun onConnectionFailed(connectionResult: ConnectionResult) {
Log.i(TAG, "Connection failed. Error: " + connectionResult.getErrorCode())
}
override fun onStart() {
super.onStart()
if (mGoogleApiClient != null) {
mGoogleApiClient!!.connect()
}
}
override fun onStop() {
super.onStop()
if (mGoogleApiClient!!.isConnected()) {
mGoogleApiClient!!.disconnect()
}
}
#SuppressLint("MissingPermission")
protected fun startLocationUpdates() {
// Create the location request
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(UPDATE_INTERVAL)
.setFastestInterval(FASTEST_INTERVAL)
// Request location updates
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
}
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,
mLocationRequest, this)
Log.d("reque", "--->>>>")
}
override fun onLocationChanged(location: Location) {
val msg = "Updated Location: " +
java.lang.Double.toString(location.latitude) + "," +
java.lang.Double.toString(location.longitude)
mLatitudeTextView!!.text = location.latitude.toString()
mLongitudeTextView!!.text = location.longitude.toString()
Toast.makeText(this, msg, Toast.LENGTH_SHORT).show()
// You can now create a LatLng Object for use with maps
val latLng = LatLng(location.latitude, location.longitude)
}
private fun checkLocation(): Boolean {
if (!isLocationEnabled)
showAlert()
return isLocationEnabled
}
private fun showAlert() {
val dialog = AlertDialog.Builder(this)
dialog.setTitle("Enable Location")
.setMessage("Your Locations Settings is set to 'Off'.\nPlease Enable Location to " + "use this app")
.setPositiveButton("Location Settings") { paramDialogInterface, paramInt ->
val myIntent = Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS)
startActivity(myIntent)
}
.setNegativeButton("Cancel") { paramDialogInterface, paramInt -> }
dialog.show()
}
companion object {
private val TAG = "MainActivity"
}
}
gradle(Module: appname.app)
buildFeatures{
viewBinding true
} // for databinding
dependencies{
implementation 'com.google.android.gms:play-services-location:18.0.0'
}
manifest:
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
activity:
class Updateposition : AppCompatActivity() {
private lateinit var bind: ActivityUpdatepositionBinding
private lateinit var fusedLocationProviderClient: FusedLocationProviderClient
//private lateinit var lat: String // :Double
//private lateinit var long: String // ||.toDouble
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
bind = ActivityUpdatepositionBinding.inflate(layoutInflater)
setContentView(bind.root)
//supportActionBar!!.hide()
fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this)
try {
getActualLocation()
//getActualLocation()
//getActualLocation()
}catch (e: java.lang.Exception){
e.printStackTrace()
}
}
private fun getActualLocation() {
val task = fusedLocationProviderClient.lastLocation
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, arrayOf(android.Manifest.permission.ACCESS_FINE_LOCATION), 101)
return
}
task.addOnSuccessListener {
if (it != null){
bind.tvLatitude.text = "${it.latitude}" // it.longitude is a Double
bind.tvLongitude.text = "${it.longitude}" // tvLongitude is a TextView
}
}
}// one curly brace could be missing (or not)
run it then close your app then run again and voila!
Related
I have an activity that is receiving the user location every X seconds. When the user location is within the radius of 15 meters from a specific point, I want the Location Provider to stop updating the user location and to start a new activity.
I have the following method to stop location updates:
private fun stopLocationUpdates() {
fusedLocationClient.removeLocationUpdates(locationCallback)
}
I call stopLocationUpdates() in both onPause() and onDestroy() methods. I've tried to call it inside the for each location cicle, when the case distance < 15 is verified. None of this seems to work.
I am trying to call finish() to finish the current activity and by using the Logcat I see that the location keeps updating, although the activity is finished.
Plus, the new activity (ExerciseActivity) keeps launching in loop.
Please, let me know how I can stop this. Thank you in advance.
I leave here the major parts of the code of this activity:
class MapActivity : AppCompatActivity() {
private val requestPermissionsRequestCode = 1
private lateinit var fusedLocationClient: FusedLocationProviderClient
private lateinit var locationCallback: LocationCallback
private lateinit var locationRequest: LocationRequest
private var allCheckpoints: List<CheckpointResult> = ArrayList()
private val mAdapterNextCheckpoints = NextCheckpointAdapter()
private var nextCheckpoints: ArrayList<CheckpointResult> = ArrayList()
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_map)
requestPermissionsIfNecessary(arrayOf(
Manifest.permission.ACCESS_COARSE_LOCATION,
Manifest.permission.ACCESS_FINE_LOCATION,
Manifest.permission.ACCESS_NETWORK_STATE,
Manifest.permission.ACCESS_WIFI_STATE,
Manifest.permission.INTERNET
))
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this)
fusedLocationClient.lastLocation
.addOnSuccessListener { location: Location? ->
if (location != null) {
mUserMarker.position = GeoPoint(location.latitude, location.longitude)
mUserMarker.setAnchor(Marker.ANCHOR_CENTER, Marker.ANCHOR_BOTTOM)
mUserMarker.title = getString(R.string.your_position)
map.overlays.add(mUserMarker)
map.controller.setCenter(mUserMarker.position)
}
}
startLocationUpdates()
}
private fun startLocationUpdates() {
locationRequest = create()
locationRequest.interval = 4000
locationRequest.priority = Priority.PRIORITY_HIGH_ACCURACY
locationCallback = object : LocationCallback() {
override fun onLocationResult(locationResult: LocationResult) {
for (location in locationResult.locations) {
mUserMarker.position = GeoPoint(location.latitude, location.longitude)
mUserMarker.setAnchor(Marker.ANCHOR_CENTER, Marker.ANCHOR_BOTTOM)
mUserMarker.title = getString(R.string.your_position)
map.overlays.add(mUserMarker)
mAdapterNextCheckpoints
if (nextCheckpoints.isNotEmpty()) {
for (checkpoint in nextCheckpoints) {
val results = FloatArray(3)
Location.distanceBetween(checkpoint.latitude,
checkpoint.longitude,
location.latitude,
location.longitude, results)
val distance = results[0]
Log.d("Distance: ", distance.toString())
if (distance <= 15) {
//stopLocationUpdates()
val i = Intent(this#MapActivity, ExerciseActivity::class.java)
i.putExtra("exerciseId", checkpoint.exercise.exerciseId)
startActivity(i)
finish()
}
}
}
}
}
}
fusedLocationClient.requestLocationUpdates(locationRequest,
locationCallback,
Looper.getMainLooper())
}
override fun onResume() {
super.onResume()
startLocationUpdates()
}
override fun onPause() {
super.onPause()
stopLocationUpdates()
}
override fun onDestroy() {
super.onDestroy()
stopLocationUpdates()
}
private fun stopLocationUpdates() {
fusedLocationClient.removeLocationUpdates(locationCallback)
}
}
Try removing startLocationUpdates() call inside onCreate() and I hope it will get you to work.
Explenation:
You are calling startLocationUpdates() method in both onCreate() and onResume() methods. So it will make two callbacks which you store the latest inside locationCallback. But you loose the first callback created when onCreate() is called. So when you call fusedLocationClient .removeLocationUpdates(locationCallback), you just remove one of the callbacks!
I am using FusedLocationProviderClient to get the location but it not giving correct Location (i.e. precise). The location it provides is 20 blocks away atleast which is not really a good solution for me.
LatLng i Need : 28.602205, 77.380126
LatLng i receive: 28.600504,77.382864
Here is code for the same
val client = LocationServices.getFusedLocationProviderClient(this)
var locationRequest = LocationRequest.create().apply {
interval = TimeUnit.SECONDS.toMillis(20)
}
client.requestLocationUpdates(locationRequest, object: LocationCallback() {
override fun onLocationAvailability(p0: LocationAvailability) {
super.onLocationAvailability(p0)
}
override fun onLocationResult(p0: LocationResult) {
super.onLocationResult(p0)
var latLong = p0.lastLocation
marker.position = LatLng(latLong!!.latitude, latLong.longitude)
Log.d("sagar", "Location result: $p0")
}
}, Looper.getMainLooper())
This question reflects back to a previous question: Show multiple registered user`s location on the same map (Android Studio, Firebase, Kotlin)
My main problem is that I have created a chatting app in Android Studio, and also added a map activity, using Google Api. I am using Firebase Realtime Database, and this is how my tree currently looks like:
I want the "userlocation" appear under each of my registered user, so all registered user`s location will will appear on my Google Map as a marker.
Here is my MapsActivity:
class MapsActivity : AppCompatActivity(), OnMapReadyCallback {
companion object {
var currentUser: User? = null
val TAG = "MapsActivity"
}
private lateinit var map: GoogleMap
private val LOCATION_PERMISSION_REQUEST = 1
private lateinit var fusedLocationClient: FusedLocationProviderClient
private lateinit var locationRequest: LocationRequest
private lateinit var locationCallback: LocationCallback
private fun getLocationAccess() {
if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
map.isMyLocationEnabled = true
getLocationUpdates()
startLocationUpdates()
}
else
ActivityCompat.requestPermissions(this, arrayOf(android.Manifest.permission.ACCESS_FINE_LOCATION), LOCATION_PERMISSION_REQUEST)
}
private fun getLocationUpdates() {
locationRequest = LocationRequest()
locationRequest.interval = 30000
locationRequest.fastestInterval = 20000
locationRequest.priority = LocationRequest.PRIORITY_HIGH_ACCURACY
locationCallback = object : LocationCallback() {
override fun onLocationResult(locationResult: LocationResult) {
if (locationResult.locations.isNotEmpty()) {
val location = locationResult.lastLocation
// val uid = FirebaseAuth.getInstance().currentUser?.uid
// val rootRef = FirebaseFirestore.getInstance()
// val usersRef = rootRef.collection("users")
// val uidRef = uid?.let { usersRef.document(it) }
// if (uidRef != null) {
// uidRef.get()
// .addOnSuccessListener { document ->
// if (document != null) {
// val latitude = document.getDouble("latitude")
// val longitude = document.getDouble("longitude")
// Log.d(TAG, ", " + location.latitude + location.longitude)
// } else {
// Log.d(TAG, "No such document")
// }
// }
// .addOnFailureListener { exception ->
// Log.d(TAG, "get failed with ", exception)
// }
// }
lateinit var databaseRef: DatabaseReference
databaseRef = Firebase.database.reference
val locationlogging = LocationLogging(location.latitude, location.longitude)
databaseRef.child("/userlocation").setValue(locationlogging)
.addOnSuccessListener {
Toast.makeText(applicationContext, "Locations written into the database", Toast.LENGTH_LONG).show()
}
.addOnFailureListener {
Toast.makeText(applicationContext, "Error occured while writing your location to the database", Toast.LENGTH_LONG).show()
}
}
}
}
}
#SuppressLint("MissingPermission")
private fun startLocationUpdates() {
fusedLocationClient.requestLocationUpdates(locationRequest,locationCallback, null)
}
#SuppressLint("MissingPermission")
override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) {
if (requestCode == LOCATION_PERMISSION_REQUEST) {
if (grantResults.contains(PackageManager.PERMISSION_GRANTED)) {
map.isMyLocationEnabled = true
} else { Toast.makeText(this, "User has not granted location access permission", Toast.LENGTH_LONG).show()
finish()
}
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_maps)
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
val mapFragment = supportFragmentManager
.findFragmentById(R.id.map) as SupportMapFragment
mapFragment.getMapAsync(this)
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this)
}
override fun onMapReady(googleMap: GoogleMap) {
map = googleMap
getLocationAccess()
}
override fun onCreateOptionsMenu(menu: Menu?): Boolean {
menuInflater.inflate(R.menu.nav_menu_map, menu)
return super.onCreateOptionsMenu(menu)
}
I commented out some of the codes as I wasn`t able to implement it properly. When I ran the code, the latitude and longitude appeared in my Logcat, but in my Realtime database, it wiped out all my data under /users and it was replaced by the latitude and longitude.
Here is my LocationLogging:
import com.google.firebase.database.IgnoreExtraProperties
#IgnoreExtraProperties
data class LocationLogging(
var Latitude: Double? = 0.0,
var Longitude: Double? = 0.0
)
I am looking to find an easy way, which puts the coordinates into my Firebase Realtime Database under each of my registered users, and show all locations on the map at the same time.
You can get the current user with the firebase auth SDK and change the path where you save the data to save it under the user path. You would need to change this part of your code:
FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
lateinit var databaseRef: DatabaseReference
databaseRef = Firebase.database.reference
val locationlogging = LocationLogging(location.latitude, location.longitude)
databaseRef.child("users").child(user.getUid()).child("userlocation").setValue(locationlogging)
.addOnSuccessListener {
Toast.makeText(applicationContext, "Locations written into the database", Toast.LENGTH_LONG).show()
}
.addOnFailureListener {
Toast.makeText(applicationContext, "Error occured while writing your location to the database", Toast.LENGTH_LONG).show()
}
I am very new to Kotlin and Android Development and really wanting to get into it. I am doing a project to help me understand and work with intent. The goal is simple, an android app that gets the users location in one activity, then passes it on to the next activity, where I intend to use it ( in the form of longitude and latitude). However I have been trying for hours to get the data to pass as an extra. The error that is show says nullpointer:
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.content.Intent.getStringExtra(java.lang.String)' on a null object reference
at com.tba.mypoint_ofinterest.LocationInfo.<init>(LocationInfo.kt:11)
The two files relevant to this are:
AddLocation.kt - This is where I get the users location. Then the user presses a button: "btn_accept" and then I want it go to the LocationInfo.kt activity.
LocationInfo.kt-This is where I want to receive the location data and where the error message keeps getting thrown.
Here is the AddLocation.kt code:
import android.content.Intent
import android.content.pm.PackageManager
import android.location.Location
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.os.Looper
import android.view.View
import android.widget.Toast
import androidx.core.app.ActivityCompat
import com.google.android.gms.location.*
import kotlinx.android.synthetic.main.activity_add_location.*
class AddLocation : AppCompatActivity() {
//variables needed for location grab
lateinit var fusedLocationProviderClient: FusedLocationProviderClient
lateinit var locationRequest: LocationRequest
lateinit var locationCallback: LocationCallback
var REQUEST_CODE = 1000
lateinit var userLocation: Location
//Deal with permissions
override fun onRequestPermissionsResult(
requestCode: Int,
permissions: Array<out String>,
grantResults: IntArray
) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults)
when (requestCode) {
REQUEST_CODE -> {
if (grantResults.size > 0) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
Toast.makeText(this, "Permission Granted", Toast.LENGTH_SHORT).show()
else
Toast.makeText(this, "Permission Denied", Toast.LENGTH_SHORT).show()
}
}
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_add_location)
//Check for permission!
if (ActivityCompat.shouldShowRequestPermissionRationale(
this,
android.Manifest.permission.ACCESS_FINE_LOCATION
)
)
ActivityCompat.requestPermissions(
this,
arrayOf(android.Manifest.permission.ACCESS_FINE_LOCATION),
REQUEST_CODE
)
else {
buildLocationRequest()
buildLocationCallback()
//Create fused provider client
fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this)
//get location
//start getting location
btnGetLocation.setOnClickListener(View.OnClickListener {
if (ActivityCompat.checkSelfPermission(
this,
android.Manifest.permission.ACCESS_FINE_LOCATION
) != PackageManager.PERMISSION_GRANTED
) {
ActivityCompat.requestPermissions(
this,
arrayOf(android.Manifest.permission.ACCESS_FINE_LOCATION),
REQUEST_CODE
)
return#OnClickListener
}
fusedLocationProviderClient.requestLocationUpdates(
locationRequest, locationCallback,
Looper.myLooper()
)
//make the button invisible after clicked
btnGetLocation.visibility = View.INVISIBLE
})
}
//Listen for clicking add location then turn off GPS and proceed to next view
btn_accept.setOnClickListener {
if (ActivityCompat.checkSelfPermission(
this,
android.Manifest.permission.ACCESS_FINE_LOCATION
) != PackageManager.PERMISSION_GRANTED
) {
ActivityCompat.requestPermissions(
this,
arrayOf(android.Manifest.permission.ACCESS_FINE_LOCATION),
REQUEST_CODE
)
}
fusedLocationProviderClient.removeLocationUpdates(locationCallback)
locationCallback = object : LocationCallback() {
override fun onLocationResult(p0: LocationResult?) {
userLocation = p0!!.locations.get(p0!!.locations.size - 1) //get last location
}
}
var long = userLocation.longitude
var lat = userLocation.latitude
addInfo(long,lat)
}
}
private fun buildLocationCallback() {
locationCallback = object : LocationCallback() {
override fun onLocationResult(p0: LocationResult?) {
var location = p0!!.locations.get(p0!!.locations.size - 1) //get last location
userLocation = location
txtLocation.text =
location.latitude.toString() + "/" + location.longitude.toString() + "and accuracy" + location.accuracy.toString()
}
}
}
private fun buildLocationRequest() {
locationRequest = LocationRequest()
locationRequest.priority = LocationRequest.PRIORITY_HIGH_ACCURACY
locationRequest.interval = 5000
locationRequest.fastestInterval = 3000
locationRequest.smallestDisplacement = 10f
}
//This gives intent and takes the GPS data to the next view to be combined with user input
fun addInfo(long:Double,lat:Double) {
val infoIntent: Intent = Intent(this, LocationInfo::class.java).apply {
putExtra("LAT_DATA", lat)
putExtra("LONG_DATA",long)
}
startActivity(infoIntent)
}
//Stop getting location data if back button is pressed
override fun onSupportNavigateUp(): Boolean {
fusedLocationProviderClient.removeLocationUpdates(locationCallback)
return super.onSupportNavigateUp()
}
}
Here is the LocationInfo.kt code:
import android.content.Intent
import android.location.Location
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import kotlinx.android.synthetic.main.activity_location_info.*
class LocationInfo : AppCompatActivity() {
val longitude = intent.getStringExtra("LONG_DATA")
val latitude = intent.getStringExtra("LAT_DATA")
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_location_info)
btnSaveLocation.setOnClickListener{view ->saveInfo(view)}
textView2.text = longitude.toString()+"/"+latitude.toString()
}
fun saveInfo(x: View?){
val saveIntent: Intent = Intent(this,MainActivity::class.java)
startActivity(saveIntent)
}
}
I don't think I really understand how to use intent properly or I am mislabeling the loction data somewhere. Any advice is welcome, thank you
The issue is you are trying to access the intent even before the onCreate() is called, as a result intent is null.
Follow this,
class LocationInfo : AppCompatActivity() {
private lateinit var longitude:Double
private lateinit var latitude:Double
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_location_info)
btnSaveLocation.setOnClickListener{view ->saveInfo(view)}
longitude = intent.getDoubleExtra("LONG_DATA",0.0)
latitude = intent.getDoubleExtra("LAT_DATA",0.0)
textView2.text = longitude.toString()+"/"+latitude.toString()
}
fun saveInfo(x: View?){
val saveIntent: Intent = Intent(this,MainActivity::class.java)
startActivity(saveIntent)
}
}
You should access the Intent in the onCreate() method.
val longitude = intent.getDoubleExtra("LONG_DATA",0.0)
val latitude = intent.getDoubleExtra("LAT_DATA",0.0)
I try to get the current Location with GM API in my application (using Android Studio). But if i click the button which triggers the getLocation() funktion, i always end up in the catch{} block and i dont know why.
My mobile device is connected for testing.
Here is the getLocation() Funktion:
fun getLocation() {
var locationManager = getSystemService(LOCATION_SERVICE) as LocationManager?
var locationListener = object : LocationListener{
override fun onLocationChanged(location: Location?) {
var latitute = location!!.latitude
var longitute = location!!.longitude
Log.i("test", "Latitute: $latitute ; Longitute: $longitute")
}
override fun onStatusChanged(provider: String?, status: Int, extras: Bundle?) {
}
override fun onProviderEnabled(provider: String?) {
}
override fun onProviderDisabled(provider: String?) {
}
}
try {
locationManager!!.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0L, 0f, locationListener)
} catch (ex:SecurityException) {
Toast.makeText(applicationContext, "Fehler bei der Erfassung!", Toast.LENGTH_SHORT).show()
}
}
Here is the onCreate Funktion:
class CurrentLocationActivity : AppCompatActivity() {
lateinit var mapFragment : SupportMapFragment
lateinit var googleMap : GoogleMap
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_current_location)
//Karte erstellen
mapFragment = supportFragmentManager.findFragmentById(R.id.map) as SupportMapFragment
mapFragment.getMapAsync(OnMapReadyCallback {
googleMap = it
})
//OnClickListener um Location zu speichern
btnGetCurrentLocation.setOnClickListener {
getLocation()
}
}
Try as follow
Step 1. Put on your AndroidManifest.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com....">
<!-- This line -->
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<application ... />
</manifest>
Step 2. Put it above your location request
import android.Manifest
import android.content.pm.PackageManager
import android.support.v4.app.ActivityCompat
import android.support.v4.content.ContextCompat
...
fun getLocation() {
...
if (ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(
this,
arrayOf(Manifest.permission.ACCESS_FINE_LOCATION),
PERMISSION_REQUEST_ACCESS_FINE_LOCATION)
return
}
locationManager!!.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0L, 0f, locationListener)
}
override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults)
if (requestCode == PERMISSION_REQUEST_ACCESS_FINE_LOCATION) {
when (grantResults[0]) {
PackageManager.PERMISSION_GRANTED -> getLocation()
PackageManager.PERMISSION_DENIED -> //Tell to user the need of grant permission
}
}
}
companion object {
private const val PERMISSION_REQUEST_ACCESS_FINE_LOCATION = 100
}
The LocationManager will throw a SecurityException if the location permission has not been granted.
Information on adding the location permissions to your app can be found here.