code: protected void addCommandsToGroupContainer(final GroupContainerPopulator groupContainerPopulator) {
  		final Iterator members = getMemberList().iterator();
  
  		while (members.hasNext()) {
  			final GroupMember member = (GroupMember) members.next();
  			if (member.getCommand() instanceof CommandGroup) {
  				member.fill(groupContainerPopulator, getButtonFactory(), getPullDownMenuButtonConfigurer(),
  						Collections.EMPTY_LIST);
  			}
  			else {
  				member.fill(groupContainerPopulator, getButtonFactory(), getDefaultButtonConfigurer(),
  						Collections.EMPTY_LIST);
  			}
  		}
  		groupContainerPopulator.onPopulated();
  	}
docs: Create a container with the given GroupContainerPopulator which will hold
  the members of this group.
  
  @param groupContainerPopulator