Android optimized event bus that simplifies communication between Activities, Fragments, Threads, Services, etc. Less code, better quality.
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EventBus is a publish/subscribe event bus optimized for Android.


  • simplifies the communication between components
    • decouples event senders and receivers
    • performs well with Activities, Fragments, and background threads
    • avoids complex and error-prone dependencies and life cycle issues
  • makes your code simpler
  • is fast
  • is tiny (~50k jar)
  • is proven in practice by apps with 100,000,000+ installs
  • has advanced features like delivery threads, subscriber priorities, etc.

    Build Status

EventBus in 3 steps

  1. Define events:

    public static class MessageEvent { /* Additional fields if needed */ }
  2. Prepare subscribers: Declare and annotate your subscribing method, optionally specify a thread mode:

    @Subscribe(threadMode = ThreadMode.MAIN)  
    public void onMessageEvent(MessageEvent event) {/* Do something */};

    Register and unregister your subscriber. For example on Android, activities and fragments should usually register according to their life cycle:

    public void onStart() {
    public void onStop() {
  3. Post events:

    EventBus.getDefault().post(new MessageEvent());

Read the full getting started guide.

Add EventBus to your project

Please ensure that you are using the latest version by checking here


compile 'org.greenrobot:eventbus:3.0.0'



Or download EventBus from Maven Central

Homepage, Documentation, Links

For more details on EventBus please check EventBus' website. Here are some direct links you may find useful:





How does EventBus compare to other solutions, like Otto from Square? Check this comparison.


Copyright (C) 2012-2016 Markus Junginger, greenrobot (

EventBus binaries and source code can be used according to the Apache License, Version 2.0.

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