How do I exit from MobileScanner prior to detection?

I'm using the following mobile_scanner code to scan for a barcode. I would like to give the user the option to exit the scanner before scanning a barcode so I'm providing an IconButton to do so.

When I click the IconButton, I get a black screen and no errors instead of being taken to the Home screen as expected. What do I need to do to make this work?

final MobileScannerController scannerController = MobileScannerController();

@override
Widget build(BuildContext context) {
return MaterialApp(
      home: Scaffold(
            body: Builder(builder: (context) {
                  return Stack(
                        children: [
                            MobileScanner(
                                allowDuplicates: false,
                                controller: scannerController,
                                onDetect: (barcode, args) async {
                                    final String code = barcode.rawValue!;

                                    Map<String, dynamic> productData =
                                        await Networking().getProductByBarcode(code);
                                    Provider.of<AppData>(context, listen: false)
                                        .setProduct(productData);
                                    Navigator.pushNamed(context, ProductDetails.id);
                                },
                            ),
                            Container(
                                alignment: Alignment.bottomLeft,
                                margin: const EdgeInsets.only(
                                    bottom: 35.0,
                                    left: 25.0,
                                ),
                                child: IconButton(
                                    onPressed: () {
                                        scannerController
                                          ..stop()
                                          ..dispose();
                                        Navigator.pop(context);
                                    },
                                    icon: const Icon(
                                        Icons.close_outlined,
                                        size: 40.0,
                                        color: Colors.white,
                                    ),
                                ),
                            ),
                        ],
                    );
                },
            ),
        ),
    );
}