public function setAttribute($key, $value = null)
    {
        if (is_null($value)) {
            $this->getAttributeMap()->remove($key);
        } else {
            $this->getAttributeMap()->set($key, $value);
        }
        return $this;
    }
public function setAttribute($key, $value = null)
    {
        if (is_null($value)) {
            $this->getAttributeMap()->remove($key);
        } else {
            $this->getAttributeMap()->set($key, $value);
        }
        return $this;
    }
public function setAttribute ( $ key , $ value = null ) { if ( is_null ( $ value ) ) { $ this -> getAttributeMap ( ) -> remove ( $ key ) ; } else { $ this -> getAttributeMap ( ) -> set ( $ key , $ value ) ; } return $ this ; }
set attribute to html element

@param       string      $key        html element attribute key
@param       string      $value      html element attribute value
@return      HtmlElementAbstract
set attribute to html element