code: public void setAction(String action)
      {
          ExtendedInfo info = getInfo(action);
          if (info != null)
              info._action = action;
      }
docs: Set the action to be called when the node is selected.  A tree node may only have a <code>action</code>
  or <code>href</code> or <code>clientAction</code> set but not both.
  @param action an action in the page flow that will run when the node is selected.