anchor.diff:        return (Stack(
           children: [
             Scandit(
  -              scanned: _handleBarcodeResult,
  +              scanned: _verifyBarcodeScanning,
                 onError: (e) => setState(() => _message = e.message),
                 symbologies: [Symbology.CODE128, Symbology.DATA_MATRIX],
                 onScanditCreated: (controller) => _controller = controller,
  
positive.code:                 child: FlatButton(
                    padding: EdgeInsets.only(left: 32.0, right: 32.0),
                    onPressed: () {
                      this.setState(() {
                        hasScanned = false;
                        hasSubmitted = false;
  
negative.code:   bool successfulSubmission;
    bool isValidBarcode;
    PermissionStatus _cameraPermissionsStatus = PermissionStatus.undetermined;
    List<String> scannedCodes = new List<String>();
  
    Future _requestCameraPermissions() async {
      var status = await Permission.camera.status;
  