code: protected ListenerController getController(Listener listener) {
  		for (ListenerController controller : listeners.keySet()) {
  			if (controller.getListener().equals(listener)) {
  				return controller;
  			}
  		}
  		return null;
  	}
docs: Get the controller that belongs to the given listener. Protected method, used by the MapWidget.
  
  @param listener
  The listeners to search for.
  @return Return the controller, or null if it could not be found.