QR code scanning for iOS and Android with an embedded MAUI CameraView

[jp-weber]

Hello,

since I have been looking for a comfortable solution to scan the required QR codes for my app (two factor authenticator via totp), I have now opted for MAUI embedding in order to be able to use the new project ZXing.Net.Maui, since ZXing.Net.Mobile has not been properly supported for ages.

Test project: https://github.com/jp-weber/UnoCameraMauiTest

I am quite impressed by the functionality and embedding of the MAUI control:

Core of the test project:
Read QR code in MAUI library and set variable in ViewModel =>

    private void BarcodesDetected(object sender, ZXing.Net.Maui.BarcodeDetectionEventArgs e)
    {
        foreach (var barcode in e.Results)
        {
            Console.WriteLine($"Barcodes: {barcode.Format} -> {barcode.Value}");
            ViewModel.Parameter = barcode.Value;
        }
    }

Send the value of the variable to the recipient in the Uno project =>

    public string Parameter
    {
        get => _parameter;
        set
        {
            if(SetProperty(ref _parameter, value) && !string.IsNullOrWhiteSpace(value))
            {
                SendParameterMessage();
            }
        }
    }

    public void SendParameterMessage()
    {
        Messenger.Send(new QRCodeScannedMessage(Parameter));
    }

And last the recipient in the Uno project

        Messenger.Register<MainPageViewModel, QRCodeScannedMessage>(this, async (viewmodel, message) =>
        {
            // on Android the UI update must be set on UI Thread, else =>
            // Android.Util.AndroidRuntimeException: Only the original thread that created a view hierarchy can touch its views
            await App.MainWindow.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () =>
            {
                viewmodel.Parameter = message.Value;
            });
            
        });

What is your opinion about this combination to realize the required functionality?

[jeromelaban]

@jp-weber thanks for showing your solution! If MAUI embedding solves your problem, it's one way to do it for sure. Maybe there will be a different "uno native" solution in the future to do this.