code: public void init(BaseMessageReceiver messageReceiver, BaseMessageFilter messageFilter)
      {
          if (messageFilter == null)
          {
              if (messageReceiver != null)
              {
                  messageFilter = messageReceiver.createDefaultFilter(this);    // Add filter to handler
                  return; // All done. (createDefaultFilter adds the message listener to the new filter)
              }
          }
          if (messageFilter != null)
              messageFilter.addMessageListener(this);     // This will also add the message filter to my list.
      }
docs: Constructor.
  @param messageReceiver The message receiver that this listener is added to.
  @param messageFilter The filter for this message listener.