I haven't used location services in a long, long time, so I'm just looking at the documentation for 'LocationRequest.Builder` and guessing at your equivalent code because it looks self-explanatory. Builders are a common pattern, used more often in Java-based APIs like this one than they are used in pure-Kotlin APIs. You can look up "java builder pattern" to read about it.
private fun NewLocation() {
val locationRequest = LocationRequest.Builder()
.setPriority(Priority.PRIORITY_HIGH_ACCURACY)
.setIntervalMillis(0L)
.setMinUpdateIntervalMillis(0L)
.setMaxUpdates(1)
.build()
mfusedlocation = LocationServices.getFusedLocationProviderClient(this)
mfusedlocation.requestLocationUpdates(locationRequest, locationCallback, Looper.myLooper())
}
FYI since you're working on a portfolio:
Function names in Kotlin start with a verb and lower-case letter by convention. Or if it returns a modified copy of an object, you can use a past participle instead of a phrase starting with a verb. For example, I would rename
NewLocation()to something likebeginLocationRequest().The
mSomethingpattern of naming variables (putting abbreviations in front of variable names) is called Hungarian notation.mstands for "member", but Kotlin properties are not even called member variables. I've never seen Hungarian notation used in Kotlin before, and it is rarely used in Java. It is widely regarded as making code less readable, especially with modern IDEs. I would advise against using it in a portfolio project as it is more likely to damage the impression you want to give than it is to help, especially if you are using it inconsistently.
LocationRequest.Builder works with 1 or 2 parameters.
This is the code that worked for me :
mLocationRequest = new LocationRequest.Builder(Priority.PRIORITY_HIGH_ACCURACY, 1000)
.setWaitForAccurateLocation(false)
.setMinUpdateIntervalMillis(500)
.setMaxUpdateDelayMillis(1000)
.build();
in my case i was importing wrong file.
this is right file "import com.google.android.gms.location.LocationRequest;"
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) {}
}