FragmentViewBinding2.kt

class MainFragment : Fragment(R.layout.main_frag2) {
  private val binding: MainFrag2Binding by viewBinding()

  override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)
    
    // ...
  }
}

ViewDataBinding.kt

fun <T : ViewDataBinding> Fragment.viewBinding(): ReadOnlyProperty<Fragment, T> =
  object : ReadOnlyProperty<Fragment, T> {
    override fun getValue(thisRef: Fragment, property: KProperty<*>): T {
      val view = thisRef.view!!
      var binding = view.getTag(R.id.fragment_binding) as? T
      if (binding == null) {
        binding = DataBindingUtil.bind(view)
        view.setTag(R.id.fragment_binding, binding)
      }
      return binding!!
    }
  }