EventBus: Registering without any @Subscribe annotated method

Question

I have a BaseFragment class which registers/unregisters itself to EventBus in onStart()/onStop(), and several child classes that inherit from it (FragmentA, FragmentB...). The base class doesn't have any methods annoted with @Subscribe, and FragmentA neither, but I want it to register anyway in case I add some in the future.

If I register an object that doesn't have any @Subscribe annotated method, I except nothing to happen, like when using SquareUp's Otto, but EventBus throws an exception :

org.greenrobot.eventbus.EventBusException: Subscriber class com.company.app.FragmentA and its super classes have no public methods with the @Subscribe annotation

Why throw an exception ? I mean, it doesn't prevent the app to run.

Is the only solution to wrap the register()/unregister() calls in BaseFragment into an ugly try ... catch or is there a cleaner workaround?

Your methods with @Subscribe annotation must be public, check all of them. — Oğuzhan Döngül, Aug 02 '16 at 12:17
@oguzhand If you read closely, you can see that I have no methods with the `@Subscribe` annotation at all. — Mickäel A., Aug 02 '16 at 12:23
can you implement a dummy annotated method in base fragment? — lelloman, Aug 02 '16 at 12:40
why don't you add an empty `@Subscribe` method? i think its throwing exception just in case user forget to add the `@Subscribe` method. — Atiq, Aug 02 '16 at 12:41

score 2 · Accepted Answer · edited Aug 08 '16 at 15:53

2

If you want your child fragments to be able to have no @Subscribe method without any exception to be thrown, just put an empty subscriber in the base class :

@Subscribe
public void dummyEvent(SomeClassThatWillNeverBePosted event) {}

edited Aug 08 '16 at 15:53

Mickäel A.

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answered Aug 08 '16 at 15:46

Atiq

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score 0 · Answer 2 · answered Aug 02 '16 at 12:32

0

I think you should register/unregister seperately for each fragment. Because if you do this in base fragment your child fragments register same events but each fragment has different events.

answered Aug 02 '16 at 12:32

faranjit

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EventBus: Registering without any @Subscribe annotated method

2 Answers2