はじめに

アプリ内でSMS受信メッセージを取得する方法について解説。

方法

1.ライブラリ導入

dependencies {
    implementation 'com.google.android.gms:play-services-auth:20.7.0'
    implementation 'com.google.android.gms:play-services-auth-api-phone:18.0.1'
}

2.レイアウト作成

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    android:id="@+id/base_view"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/edit_text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:textSize="36sp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>

内部処理作成

SMSが受信されたことを検知するBroadcastReceiverを作成し、onResume()時に登録、onPause()時に登録解除する。

class MainActivity : AppCompatActivity() {
    /** ViewBinding */
    private val binding by lazy { ActivityMainBinding.inflate(layoutInflater) }

    /** SMSレシーバー */
    private val smsReceiver = object : BroadcastReceiver() {
        override fun onReceive(context: Context?, intent: Intent?) {
            if (intent?.action == SmsRetriever.SMS_RETRIEVED_ACTION) {

                val status = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
                    intent.getParcelableExtra(SmsRetriever.EXTRA_STATUS, Status::class.java)
                } else {
                    intent.getParcelableExtra(SmsRetriever.EXTRA_STATUS)
                }

                if (status?.statusCode == CommonStatusCodes.SUCCESS) {
                    val consentIntent = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
                        intent.getParcelableExtra(SmsRetriever.EXTRA_CONSENT_INTENT, Intent::class.java)
                    } else {
                        intent.getParcelableExtra(SmsRetriever.EXTRA_CONSENT_INTENT)
                    }
                    requestSmsResult.launch(consentIntent)
                }
            }
        }
    }

    /** SMSリクエスト結果 */
    private val requestSmsResult = registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
        if (result?.resultCode == Activity.RESULT_OK) {
            binding.editText.setText(result.data?.getStringExtra(SmsRetriever.EXTRA_SMS_MESSAGE)?.filter { it.isDigit() })
        }
    }

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(binding.root)
    }

    override fun onResume() {
        super.onResume()

        val intentFilter = IntentFilter(SmsRetriever.SMS_RETRIEVED_ACTION)
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
            registerReceiver(smsReceiver, intentFilter, Context.RECEIVER_NOT_EXPORTED)
        } else {
            registerReceiver(smsReceiver, intentFilter)
        }

        SmsRetriever.getClient(this).startSmsUserConsent(null)
    }

    override fun onPause() {
        super.onPause()
        unregisterReceiver(smsReceiver)
    }
}