anchor.diff:    bool _validateSecretLength = false;
     _QrScanState _qrState = _QrScanState.none;
     bool _isObscure = true;
  +  List<int> _periodValues = [20, 30, 45, 60];
  +  List<int> _digitsValues = [6, 8];
   
     _scanQrCode(QrScanner qrScanner) async {
       try {
  
positive.code:             final b64Image = base64Encode(fileData);
              final otpauth = await qrScanner.scanQr(b64Image);
              final data = CredentialData.fromUri(Uri.parse(otpauth));
              setState(() {
                _issuerController.text = data.issuer ?? '';
                _accountController.text = data.name;
                _secretController.text = data.secret;
                _oathType = data.oathType;
                _hashAlgorithm = data.hashAlgorithm;
                _periodController.text = '${data.period}';
                _digits = data.digits;
                _qrState = _QrScanState.success;
              });
            }
          },
          child: Column(
  
negative.code:                             defaultPeriod,
                          isDense: true,
                          underline: null,
                          items: _periodValues
                              .map((e) => DropdownMenuItem(
                                    value: e,
                                    child: Text('$e sec'),
  