public function setDisplayIcon( $displayIcon )
    {
        if ( empty( $displayIcon ) )
        {
            $displayIcon = array();
        }
        else if ( $displayIcon instanceof Traversable )
        {
            $displayIcon = ArrayUtils::iteratorToArray( $displayIcon );
        }
        else if ( ! is_array( $displayIcon ) )
        {
            $displayIcon = (array) $displayIcon;
        }

        $this->displayIcon = $displayIcon;
        return $this;
    }