Using Rx Framework for async calls using the void AsyncMethod(Action callback) pattern

Question

I\'ve seen tons of examples on how to use the Observable.FromAsyncPattern() in the Rx Framework to simplify Async calls, but I\'m using an interface that doesn\'t use the st

Answer 1

I like Observable.Create for this, but @dahlbyk answer is incorrect(misses completion and performs the action in the unsubscribe handler). Should be something like this:

    IObservable> FromListCallbackPattern(
        Action>> listGetter)
    {
        return Observable
            .Create>(observer =>
            {
                var subscribed = true;
                listGetter(list =>
                {
                    if (!subscribed) return;
                    observer.OnNext(list);
                    observer.OnCompleted();
                });
                return () =>
                {
                    subscribed = false;
                };
            });
    }

Also, since the originating API returns an entire list altogether, I don't see a reason to transform it to observable too early. Let the resulting observable return a list as well, and if a caller needs to flatten it, he can use .SelectMany