Access view binding in Fragment from Activity

I am upgrading an application to remove all synthetics and use the new ViewBinding feature. So far everything works as long as you are inside of the class/layout you are accessing, but I have synthetic references to layout elements in my Main Activity.

In class Fragment:

    private var _binding: FragmentBinding? = null
    val binding get() = _binding!!
    private val compositeDisposable = CompositeDisposable()

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {
        _binding = FragmentBinding.inflate(inflater, container, false)
        return binding.root

In MainActivity I have:

    private lateinit var mainBinding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        mainBinding = ActivityMainBinding.inflate(layoutInflater)

I have methods for dialogs which use synthetics to dim layout elements in the Fragment.

//textView on fragment layout.xml
textView?.alpha = someFloat

This works fine when synthetic, however I cannot get the new view binding to work based on Android’s documention. How can I easily mimic the synthetic behavior with ViewBinding? So far it has increased the code by a large amount and does not work unless the Fragment’s view has been created and has honestly made the code worse and harder to understand. I attempted to use bind off the the main activity layout root view but I got "view must have a tag" errors, and all layouts start with <layout>. Any help is appreciated.

Source: Android Questions