Turn on GPS Programmatically in Android 4.4 or Higher

if (isGpsOff())
{
    tryGpsOn()
}

private fun isGpsOff():Boolean {
    return !(getSystemService(Context.LOCATION_SERVICE) as LocationManager).isProviderEnabled(LocationManager.GPS_PROVIDER)
}

private fun tryGpsOn() {
    val googleApiClient:GoogleApiClient = GoogleApiClient.Builder(applicationContext).addApi(LocationServices.API).build()
    googleApiClient.connect()


    val builder:LocationSettingsRequest.Builder = LocationSettingsRequest.Builder().addLocationRequest(LocationRequest.create().apply {
        priority = LocationRequest.PRIORITY_HIGH_ACCURACY;
        interval = 30 * 1000;
        fastestInterval = 5 * 1000;
    })
    builder.setAlwaysShow(true) // this is the key ingredient

    val result= LocationServices.SettingsApi .checkLocationSettings(googleApiClient, builder.build())
    result.setResultCallback {
        result: LocationSettingsResult ->

        val status = result.status
        val state = result .getLocationSettingsStates()

        when(status.getStatusCode())
        {
            LocationSettingsStatusCodes.SUCCESS->{}
            LocationSettingsStatusCodes.RESOLUTION_REQUIRED->{
                try {
                    status.startResolutionForResult(this@RenewalPlaceActivity, 1000);
                }
                catch (e: IntentSender.SendIntentException)
                {

                }
            }
            LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE->{}
        }
    }

}

Reference Link : https://www.instructables.com/id/Turn-on-GPS-Programmatically-in-Android-44-or-High/