如何在Kotlin中的片段中使用按钮在片段之间切换？

<Button
    android:id="@+id/switchButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Switch to Fragment B" />

class FragmentA : Fragment() {
    private lateinit var switchButton: Button

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        val view = inflater.inflate(R.layout.fragment_a, container, false)
        switchButton = view.findViewById(R.id.switchButton)
        switchButton.setOnClickListener {
            val fragmentB = FragmentB()
            val transaction = requireActivity().supportFragmentManager.beginTransaction()
            transaction.replace(R.id.fragmentContainer, fragmentB)
            transaction.addToBackStack(null)
            transaction.commit()
        }
        return view
    }
}

class FragmentB : Fragment() {
    private lateinit var backButton: Button

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        val view = inflater.inflate(R.layout.fragment_b, container, false)
        backButton = view.findViewById(R.id.backButton)
        backButton.setOnClickListener {
            requireActivity().supportFragmentManager.popBackStack()
        }
        return view
    }
}

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        val fragmentA = FragmentA()
        supportFragmentManager.beginTransaction()
            .add(R.id.fragmentContainer, fragmentA)
            .commit()
    }
}