Rx.NET Call function again direct after all it's callbacks

Question

I want to make communication with serial port - get some data. I want to get this data in loop as fast as it's possible. So, i have function GetData() with callback, which draws data on the WPF form. How can I call this GetData function in loop right after all it's callbacks?

Like cycle GetData->Draw->GetData->Draw and so on?

Upd: Mb something like this?

var ob = Observable.Create<Data>(
  observer => {
    while(true) {
      observer.OnNext(GetDataFromSerialPort());
    }
});

score 4 · Accepted Answer · answered Feb 22 '16 at 08:36

I would create a service that exposed the serial Port data via an observable sequence. I would then inject that into my MVVM stack.

The Service would like similar to what you have, but with disposal functionality

public class MySerialPortService : IsCancellationRequested
{
    public IObservable<Data> GetData()
    {
        return Observable.Create<Data>(async (o, cts) =>
          observer => {
            while (!cts.IsCancellationRequested) {
              observer.OnNext(GetDataFromSerialPort());
            }
        });
    }
}

public class MyViewModel : IDisposable
{
    private readonly IMySerialPortService _mySerialPortService;
    private readonly ISchedulerProvider _schedulerProvider;
    private readonly SingleAssignmentDisposable _subscription = new SingleAssignmentDisposable();

    public MyViewModel(IMySerialPortService mySerialPortService, ISchedulerProvider schedulerProvider)
    {
        _mySerialPortService = mySerialPortService;
        _schedulerProvider = schedulerProvider;
    }

    public void Start()
    {
        _subscription.Disposable = _mySerialPortService.GetData()
            .SubscribeOn(_schedulerProvider.Background) //or _schedulerProvider.ThreadPool, or CreateEventLoopScheduler or what ever you do internally.
            .ObserveOn(_schedulerProvider.Foreground)   //or _schedulerProvider.Dispatcher etc...
            .Subscribe(
                val=> Update(val),
                ex=> ...
            )
    }

    public void Dispose()
    {
        _subscription.Dispose();
    }
}

The following post may be helpful - https://github.com/LeeCampbell/RxCookbook/tree/master/IO/Disk. It shows you step by step how to create and Observable Sequence that reads from Disk. You can swap the Disk IO for Serial Port IO.

Rx.NET Call function again direct after all it's callbacks

1 Answers1