【Kotlin】How to Use SeekBar 2

MainActivity.kt

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

        val textView = findViewById<TextView>(R.id.textView)
        val seekbar = findViewById<SeekBar>(R.id.seekbar)
        val button = findViewById<Button>(R.id.button)

        // 初期値を表示
        textView.text = "${seekbar.progress}"
    }
}