how to detect two property in reactiveui

Question

I am using reactiveui.

I want to run a some task based on the state of 2 properties.

How can I make the task run when sw1 is true and sw2 is false?

I tried as below but it doesn't work.

    private bool Ch1SW { get; set; }
    private bool Ch2SW { get; set; }
    
    this.WhenAnyValue(x => x.Ch1SW , x => x.Ch2SW , (sw1, sw2) => (sw1, sw2))
        .Where(sw => sw.sw1 == true && sw.sw2 == false)
        .ObserveOn(RxApp.MainThreadScheduler)
        .Subscribe(async x => { //some work });

Answer 1

The properties have to be public and you need to have the property changed mechanism implemented. If you are using reactiveui the easiest way is to add the [Reactive] attribute over the property declaration (from the ReactiveUI.Fody package). Then the WhenAnyValue will return the IObservable you can directly subscribe to and execute your function.

[Reactive]
public bool Ch1SW { get; set; }
[Reactive]
public bool Ch2SW { get; set; }

public MyViewModel()
{
    this.WhenAnyValue(x => x.Ch1SW, x => x.Ch2SW).Subscribe(MyAsyncFunc);
}

private async void MyAsyncFunc((bool, bool) chsw)
{
    if (chsw.Item1 && !chsw.Item2)
    {
        await System.Threading.Tasks.Task.Delay(500);
        Debug.WriteLine("Done!");
    }
}

EDIT: The [Reactive] still requires the class to inherit from ReactiveObject