title: Bypass Kotlin "Property getter or setter expected"
body: <p>I need to create a private field and use it without access to it from other classes. But i can't instantiate it in a constructor. 
  I'm developing for Android, and a problematic field screenWakeLocker can`t be instantiated this way: </p>
  
  <pre><code>class MainActivity : AppCompatActivity() {
  private val screenWakeLocker: PowerManager.WakeLock = 
                              (getSystemService(Context.POWER_SERVICE) as PowerManager)
                              .newWakeLock(PowerManager.FULL_WAKE_LOCK, "")
  </code></pre>
  
  <p>"System services not available to Activities before onCreate()"</p>
  
  <p>So i instantiate it in OnCreate:</p>
  
  <pre><code>class MainActivity : AppCompatActivity() {
  private var game: Game = Game()
  private var screenWakeLocker?: PowerManager.WakeLock;
  
  override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      setContentView(R.layout.activity_main)
      screenWakeLocker = (getSystemService(Context.POWER_SERVICE) as PowerManager).newWakeLock(PowerManager.FULL_WAKE_LOCK, "")
  }
  
  override fun onResume(){
      super.onResume()
      screenWakeLocker.acquire()
  }
  </code></pre>
  
  <p>and get a compilation error "Property getter or setter expected" at ?: PowerManager.WakeLock</p>
  
  <p>How to make it unavailable to other classes and to use it?</p>