code: public void setItemAttribute(TreeHtmlAttributeInfo attr)
      {
          _child = true;
          if (_attributes == null)
              _attributes = new ArrayList();
          _attributes.add(attr);
      }
docs: This method is called by the children tags of the TreeItem.  If there is a <code>TreeHtmlAttribute</code>
  it will set the attribute name and value.
  @param attr