Androidで画面ON / OFF を検知する

実装

Receiverを作っておく

class ScreenStateReceiver(
    private val onScreenOn: () -> Unit,
    private val onScreenOff: () -> Unit
) : BroadcastReceiver() {

    override fun onReceive(context: Context, intent: Intent) {
        when (intent.action) {
            Intent.ACTION_SCREEN_ON -> onScreenOn()
            Intent.ACTION_SCREEN_OFF -> onScreenOff()
        }
    }
}

コールバック式にしておくことで汎用的に使いやすくする

あとはActivity側で上記のレシーバーを登録する

class MainActivity : AppCompatActivity() {

    private lateinit var receiver: ScreenStateReceiver

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

        receiver = ScreenStateReceiver(
            onScreenOn = {
                Log.d("Screen", "画面ON")
            },
            onScreenOff = {
                Log.d("Screen", "画面OFF")
            }
        )
    }

    override fun onStart() {
        super.onStart()

        val filter = IntentFilter().apply {
            addAction(Intent.ACTION_SCREEN_ON)
            addAction(Intent.ACTION_SCREEN_OFF)
        }
        registerReceiver(receiver, filter)
    }

    override fun onStop() {
        super.onStop()
        unregisterReceiver(receiver)
    }
}

結果

ログ出力の結果はこんな感じになります

D/Screen: 画面OFF
D/Screen: 画面ON