Hi guys,
This is not really an add-on, at least right now, but an exploratory Vaadin fork to implement a new reactive API in Vaadin and eventually rewrite the whole event and data-binding system on top of that.
The basic primitive in this API is called Flow, representing a stream of values that can be subscribed to. Flows are analoguous - and quite similar - to Observables in the Rx family of libraries. Flows are, in a sense, dual to Streams in Java 8; instead of
pulling
values from a Stream, Flows
push
values to a consumer. This makes them very useful for representing asynchronous sequences of values such as UI events. Flows should eventually come with a similarly rich set of combinators as Streams do; currently the most fundamental ones are implemented (map, filter, reduce, flatMap etc.)
The second planned part of the API is a way to bind Flows to UI components. Instead of discrete events, components would provide composable event flows, and conversely allow binding of any properties to flows. For instance, the disabled state of a component could be bound to a flow of booleans.
Hopefully you find this interesting. Any questions, comments, and propositions are more than welcome!