Flutter Biometry

tip

Package: https://pub.dev/packages/local_auth

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Implementation Date: Jul/23

Version: 2.1.6

Description Methods

• Device Has Biometrics: check if have biometrics methods on device;
• Get Available Biometrics: Differente devices have diferent methods;
• Autenticate: Let OS determine authentication method;
• Cancel Authentication;

Abstract Class

abstract class BiometricsService {
  Future<bool> deviceHasBiometrics();
  Future<List<BiometricType>> getAvailableBiometrics();
  Future<bool> autenticate({required String authReason});
  Future<bool> authenticateWithBiometrics({required String authReason});
  Future<bool> cancelAuthentication();
}

Implementation Class

class LocalAuth implements BiometricsService {
  final LocalAuthentication auth;

  LocalAuth(this.auth);

  @override
  Future<bool> autenticate({required String authReason}) async {
    bool authenticated = false;
    try {
      authenticated = await auth.authenticate(
        authMessages: const [
          AndroidAuthMessages(
            signInTitle: 'Confirmar sua identidade',
            cancelButton: 'Cancelar',
          ),
          IOSAuthMessages(
            cancelButton: 'Cancelar',
          )
        ],
        localizedReason: authReason,
        options: const AuthenticationOptions(
          stickyAuth: true,
        ),
      );
    } on PlatformException catch (e) {
      log(e.toString());
      log(StackTrace.current.toString());
    }
    return authenticated;
  }

  @override
  Future<bool> authenticateWithBiometrics({required String authReason}) async {
    bool authenticated = false;
    try {
      authenticated = await auth.authenticate(
        localizedReason: authReason,
        options: const AuthenticationOptions(
          stickyAuth: true,
          biometricOnly: true,
        ),
        authMessages: const [
          AndroidAuthMessages(
            signInTitle: 'Confirmar sua identidade',
            cancelButton: 'Cancelar',
            biometricHint: '',
          ),
          IOSAuthMessages(
            cancelButton: 'Cancelar',
          )
        ],
      );
      return authenticated;
    } on PlatformException catch (e) {
      e.runtimeType;
      log(e.toString());
      log(StackTrace.current.toString());

      return false;
    }
  }

  @override
  Future<bool> cancelAuthentication() async {
    return await auth.stopAuthentication();
  }

  @override
  Future<bool> deviceHasBiometrics() async {
    late bool canCheckBiometrics;
    try {
      canCheckBiometrics = await auth.canCheckBiometrics;
    } on PlatformException catch (e) {
      canCheckBiometrics = false;
      log(e.toString());
      log(StackTrace.current.toString());
    }

    return canCheckBiometrics;
  }

  @override
  Future<List<BiometricType>> getAvailableBiometrics() async {
    late List<BiometricType> availableBiometrics;
    try {
      availableBiometrics = await auth.getAvailableBiometrics();
    } on PlatformException catch (e) {
      availableBiometrics = <BiometricType>[];
      log(e.toString());
      log(StackTrace.current.toString()); 
    }

    return availableBiometrics;
  }
}

danger

Contributor: BrAcInhO