Manifest.permission 에서 permission Unresolved reference 라고 나옵니다..

  R.id.action_add_photo ->{

                if(ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED){

                    startActivity(Intent(this,AddPhotoActivity::class.java))

                }

                return true

            }