{ val f = supportFragmentManager.findFragmentById(android.R.id.content ) if (f is EditFragment) { f.onBackPressed( ) } else { super.onBackPressed( ) } } } class EditFragment : Fragment() { … fun onBackPressed() { // show discard confirm dialo g } }
FragmentOnAttachListener { fragmentManager, fragment - > if (fragment is SettingFragment) { // do somethin g } } override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState ) childFragmentManager.addFragmentOnAttachListener(listener ) } … }