OnClickListener 実装例

class BasicPatternActivity : AppCompatActivity() {

private lateinit var binding: ActivityMainBinding

override fun onCreate(savedInstanceState: Bundle?) {

super.onCreate(savedInstanceState)

binding = ActivityMainBinding.inflate(layoutInflater)

setContentView(binding.root)

binding.button.setOnClickListener(object : View.OnClickListener{

override fun onClick(v: View?) {

// TODO: ボタンクリック時の処理

}

})

}

}

class Pattern1Activity : AppCompatActivity() {

private lateinit var binding: ActivityMainBinding

override fun onCreate(savedInstanceState: Bundle?) {

super.onCreate(savedInstanceState)

binding = ActivityMainBinding.inflate(layoutInflater)

setContentView(binding.root)

binding.button.setOnClickListener {

// TODO: ボタンクリック時の処理

}

}

}

class Pattern2Activity : AppCompatActivity(), View.OnClickListener {

private lateinit var binding: ActivityMainBinding

override fun onCreate(savedInstanceState: Bundle?) {

super.onCreate(savedInstanceState)

binding = ActivityMainBinding.inflate(layoutInflater)

setContentView(binding.root)

binding.button.setOnClickListener(this)

}

override fun onClick(v: View?) {

// eg. Button1, 2, 3 の分岐

if (v is Button) {

val message: String = when (v.id) {

R.id.button1 -> "button1 clicked!"

R.id.button2 -> "button2 clicked!"

else -> "button3 clicked!"

}

Toast.makeText(applicationContext, message, Toast.LENGTH_SHORT).show()

}

}

}

class Pattern3Activity : AppCompatActivity() {

private lateinit var binding: ActivityMainBinding

private val buttonClickListener = View.OnClickListener {

// TODO: ボタンクリック時の処理

}

override fun onCreate(savedInstanceState: Bundle?) {

super.onCreate(savedInstanceState)

binding = ActivityMainBinding.inflate(layoutInflater)

setContentView(binding.root)

binding.button.setOnClickListener(buttonClickListener)

}

}