title: How do you use GWT's SimpleEventBus or EventBus?
body: <p>I'm working on developing some simple graphing software which needs to be implemented in both swing and gwt.  On the gwt side, I'm going to use gwt-g2d for the canvas.  I was hoping to use an eventbus across both implementations to simplify some of the software.</p>
  
  <p>My understanding is that it should be something like this:</p>
  
  <ol>
  <li>Instantiate EventBus</li>
  <li>Instantiate Parent Widget, sink the events you want for the EventBus (mouseover or rpc callback, for example)</li>
  <li>Set EventBus to listen for events from the Parent Widget.</li>
  <li>Instantiate child widgets, who should register with the EventBus the listeners it has (Do they need to register events they might fire?)</li>
  <li>When the EventBus receives an event, it should make a decision about the event and then act on that decision, whether that means ignoring it, changing the event type, or just relaying it to all applicable child widgets.</li>
  </ol>
  
  <p>Is this generally how it should work?  SimpleEventBus is still sort of new, and I can't find much on web about how to really use it.</p>