ReactiveList and WhenAny

c#, reactiveui

Solution

This is testing when someone sets the list itself, i.e. when:

this.List1 = new ReactiveList<Foo>();

Instead, you want something like:

this.WhenAnyObservable(x => x.List1.ItemChanged, x => x.List2.ItemChanged)
    .Where(x => x.PropertyName == "IsChecked")
    .Select(_ => List1.Any(x => x.IsChecked) && List2.Any(x => x.IsChecked));

Problem

I have a number of check lists held in `ReactiveLists` that have `ChangeTrackingEnabled = true`. I want to only enable my OkCommand when there is at least one item checked in each list. In addition there are various other properties that I want to ensure are filled in with a valid byte value. I've tried doing the following but it doesn't work: ``` this.OkCommand = new ReactiveCommand(this.WhenAny( x => x.Property1, x => x.Property1, x => x.Property1, x => x.List1, x => x.List2, x => x.List3, (p1, p2, p3, l1, l2, l3) => { byte tmp; return byte.TryParse(p1.Value, out tmp) && byte.TryParse(p2.Value, out tmp) && byte.TryParse(p3.Value, out tmp) && l1.Value.Any(x => x.IsChecked) && l2.Value.Any(x => x.IsChecked) && l3.Value.Any(x => x.IsChecked); })); ``` It seems the property change notifications aren't being propagated to WhenAny. Any idea what I should be doing?

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