[Bug]: ReactiveCommand Observable does not propagate results

[Micha-kun]

Describe the bug 🐞

I don't know if it's a bug or something I'm doing wrong...

I have a ReactiveCommand that returns an IEnumerable and I'm trying to chain those results to another pipeline, like in this code example:

this.WhenActivated(
    d =>
    {
       this.GetDataCommand.Do(_ => { }).Subscribe().DisposeWith(d);
       this.GetDataCommand.Execute().Subscribe().DisposeWith(d);
    });

....

[ReactiveCommand]
private Task<IEnumerable> GetData(CancellationToken ct){
     return Task.FromResult([]);
}

The GetDataCommand RC is a Task method with Unit as Input and IEnumerable as Output. this.GetDataCommand.Execute() really executes succesfully, but, unexpectedly, the Do method attached before to the command never executes after. I tried to wrap command inside this.WhenAnyObservable() without exit. What I'm doing wrong? At first I thought it was because I was using ReactiveUI.SourceGenerators, but I tried with plain ReactiveCommands with the same results. I tried removing those DisposeWith(d) too and nothing changed.

My app is a Winforms app in .Net 8. ViewModel is in a Class Library only for ViewModels.

Step to reproduce

1 - Test my sample.

Reproduction repository

https://github.com/reactiveui/ReactiveUI

Expected behavior

Do/Select/Subscribe code executing

Screenshots 🖼️

No response

IDE

Visual Studio 2022

Operating system

Windows

Version

11

Device

PC

ReactiveUI Version

20.1.63

Additional information ℹ️

No response

[ChrisPulman]

@Micha-kun please could you provide a Repo with the code so that we can assist you, I have tried the code you have shown and this works as expected.

[Micha-kun]

I was trying too in a clean app and cannot replicate too, so I was wondering if the problem comes with RxApp initialization... Because in my app i'm using Splat.Microsoft.Extensions.DependencyInjection to initialize Splat with Generic Host but there is a problem because i'm using https://github.com/alex-oswald/WindowsFormsLifetime for a better integration of Winforms hosting into Generic Host and it generates a problem:

During service initialization, it's called under one thread but WindowsFormsLifetime, after that, creates a new thread for Winforms form in a new STA thread. Doing that, because Splat initialization is done in another thread, RxApp.MainThread is using a wrong "UI thread", not the one WindowsFormsLifetime creates. What I did to fix that is replace it when it calls the main form with a ControlScheduler, and it's fine but, is there a way to regenerate it using ReactiveUI api?

Thanks

GitHub

GitHub - alex-oswald/WindowsFormsLifetime: Windows Forms hosting extensions for the .NET Generic Host

Windows Forms hosting extensions for the .NET Generic Host - alex-oswald/WindowsFormsLifetime

[ChrisPulman]

Perhaps try using reactivemarbles.extensions.hosting.reactiveui.winforms

[Micha-kun]

I didn't know those extensions, thanks! I need to investigate them 👍

[ChrisPulman]

How did you get on with the Reactivemarbles.Extensions.Hosting packages?