Location wrapper for LiveData

LocationLiveData.kt

import android.Manifest
import android.annotation.SuppressLint
import android.app.Activity
import android.arch.lifecycle.LiveData
import android.content.Context
import android.content.pm.PackageManager
import android.location.Location
import android.os.Looper
import android.support.v4.app.ActivityCompat
import android.support.v4.content.ContextCompat
import com.google.android.gms.location.LocationCallback
import com.google.android.gms.location.LocationRequest
import com.google.android.gms.location.LocationResult
import com.google.android.gms.location.LocationServices

class LocationLiveData(private val context: Context,
                       private val locationRequest: LocationRequest = LocationRequest()) : LiveData<Location>() {

    private val fusedLocationClient = LocationServices.getFusedLocationProviderClient(context)

    private val callback = object : LocationCallback() {
        override fun onLocationResult(locationResult: LocationResult) {
            super.onLocationResult(locationResult)
            value = locationResult.lastLocation
        }
    }

    @SuppressLint("MissingPermission")
    override fun onActive() {
        super.onActive()

        if (hasPermission(context)) {
            fusedLocationClient.requestLocationUpdates(locationRequest, callback, Looper.getMainLooper())
        }
    }

    override fun onInactive() {
        super.onInactive()
        fusedLocationClient.removeLocationUpdates(callback)
    }

    companion object {

        fun hasPermission(context: Context): Boolean {
            return ContextCompat.checkSelfPermission(context, Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED
        }

        fun requestPermission(activity: Activity, requestCode: Int) {
            ActivityCompat.requestPermissions(activity, arrayOf(Manifest.permission.ACCESS_COARSE_LOCATION), requestCode)
        }
    }
}