Question

I am just switched from using Otto to RxAndroid for event bus usage mainly.

On Otto I was able to use @produce to get the last value of an event, in case an activity/fragment wasn't subscribed yet. I cant figure out how this is done by using RxAndroid.

I need this so I can receive an event from activity/fragment a to activity/fragment b.

Using a singleton instance of this class over the entire app

public class RxBus {

  private final Subject<Object, Object> bus = new SerializedSubject<>(PublishSubject.create());

  public void send(Object object) {
      bus.onNext(object);
  }

  public Observable<Object> toObserverable() {
      return bus;
  }
}

sending data from ActivityA.java

@Inject RxBus bus;
..
bus.send(new DataEvent());
..

to ActivityB.java

..
CompositeSubscription subscription = new CompositeSubscription();
ConnectableObservable<Object> dataEventEmitter = bus.toObserverable().publish();
subscription.add(dataEventEmitter.subscribe(new Action1<Object>() {
   @Override
   public void call(Object o) {
      Toast.makeText(context, "DataEvent", Toast.LENGTH_SHORT).show();
   }
}));
subscription.add(dataEventEmitter.connect());  
..

But this isn't receiving any event tho. I thought using ConnectableObservable should work but doesn't.

I also found out using

private final Subject<Object, Object> bus = new SerializedSubject<>(BehaviorSubject.create());

instead of

private final Subject<Object, Object> bus = new SerializedSubject<>(PublishSubject.create());

Does receive the last event. But this is not always the needing case through out the entire app. Couldn't find any examples so I am asking for help.

RxAndroid fetch value last event

0 个答案: