transformEvents method
- @Deprecated('Use `on<Event>` with an `EventTransformer` instead. ' 'Will be removed in v8.0.0')
- Stream events,
- TransitionFunction<
dynamic, PeersState> transitionFn
@Deprecated - Use on<Event>
with an EventTransformer
instead.
Will be removed in v8.0.0
Transforms the events
stream along with a transitionFn
function into
a Stream<Transition>
.
Events that should be processed by mapEventToState
need to be passed to
transitionFn
.
By default asyncExpand
is used to ensure all events
are processed in
the order in which they are received.
You can override transformEvents
for advanced usage in order to
manipulate the frequency and specificity with which mapEventToState
is
called as well as which events
are processed.
For example, if you only want mapEventToState
to be called on the most
recent Event
you can use switchMap
instead of asyncExpand
.
@override
Stream<Transition<Event, State>> transformEvents(events, transitionFn) {
return events.switchMap(transitionFn);
}
Alternatively, if you only want mapEventToState
to be called for
distinct events
:
@override
Stream<Transition<Event, State>> transformEvents(events, transitionFn) {
return super.transformEvents(
events.distinct(),
transitionFn,
);
}
Implementation
@Deprecated(
'Use `on<Event>` with an `EventTransformer` instead. '
'Will be removed in v8.0.0',
)
Stream<Transition<Event, State>> transformEvents(
Stream<Event> events,
TransitionFunction<Event, State> transitionFn,
) {
return events.asyncExpand(transitionFn);
}