fragmentfactory_custom_activity_with_fragmentfactory.kt

class MyActivity() : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        supportFragmentManager.fragmentFactory = FragmentFactoryImpl()        
        super.onCreate(savedInstanceState)
        ...
        val fragment = supportFragmentManager.fragmentFactory.instantiate(classLoader,    MyFragment::class.java.name)
        supportFragmentManager.beginTransaction()
            .replace(R.id.fragment_layout, fragment)
            .commitNow()
        ...