问数据库子不接受变量的值？

EN

inner class myLocarionListenr: LocationListener {
        val us4 = intent.getStringExtra("user")

        constructor(){
            myLocation = Location("me")
            myLocation!!.longitude = 0.0
            myLocation!!.latitude =0.0
        }
        override fun onLocationChanged(location: Location?) {
            myLocation = location
            val longtude = myLocation!!.longitude
            val latetude = myLocation!!.latitude


            val myDatabase:DatabaseReference = FirebaseDatabase.getInstance().getReference("user's location")
            val ulocation = com.example.firebase.location(us4,longtude,latetude)


            myDatabase.child(us4).child("locations").setValue(ulocation).addOnCompleteListener {
                Toast.makeText(this@MapsActivity,"location saved",Toast.LENGTH_LONG).show()
            }