fragmentfactory_custom_activity_without_fragmentfactory.kt

class MyActivity() : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        ...
        val fragment = MyFragment.newInstance("my argument")
        supportFragmentManager.beginTransaction()
            .replace(R.id.fragment_layout, fragment)
            .commitNow()
        ...