implementing FragmentPagerAdapter in a Fragment

MyFragmentPagerAdapter.kt

class MyFragmentPagerAdapter(
    private val context: Context,
    fragmentManager: FragmentManager
) : FragmentPagerAdapter(fragmentManager) {
    override fun getCount() = 2
    
    override fun getItem(position: Int) = when(position) {
        0 -> FirstFragment()
        1 -> SecondFragment()
        else -> throw IllegalStateException("Unexpected position $position")
    }
   
    override fun getPageTitle(position: Int): CharSequence = when(position) {
        0 -> context.getString(R.string.first)
        1 -> context.getString(R.string.second)
        else -> throw IllegalStateException("Unexpected position $position")
    }
}

ParentFragment.kt

import kotlin.synthetic...

class ParentFragment: Fragment() {
    override fun onCreateView(...) = ...
  
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        viewPager.adapter = MyFragmentPagerAdapter(requireContext(), childFragmentManager)
        tabLayout.setupWithViewPager(viewPager)
    }
}