public function setLegendClassName($legendClassName)
    {
        $event = new SetLegendClassNameEvent($legendClassName, $this);
        $this->dispatchEvent($event);
        $legendClassName = $event->getLegendClassName();

        $this->legendClassName = (string) $legendClassName;
        $this->legendClass     = new \ReflectionClass($this->legendClassName);
        return $this;
    }