DetectingVisibilityFragment.kt

public class DetectingVisibilityFragment extends Fragment {
      // will talk about this flag later
    private var isVisibleToUser: Boolean = true
    private var awaitingRunnable: Runnable? = null

    // triggered when notification from Server or client EventBus came
    override fun onNotification(newName: String) {
        if(isVisibleToUser) show(newName) 
        else awaitingRunnable = () -> show(newName)
    }

    // some methods that I tried to find in standard Fragment API
    override fun onBecomesVisible(isVisible: Boolean) {
        isVisibleToUser = isVisible
        awaitingRunnable?.let {awaitingRunnable.run()}
    }
  
}