src/Module.php
public function attach(EventManagerInterface $events)
    {
        $events->attach(ViewEvent::EVENT_RENDERER_POST, array($this, 'cleanLayout'), 1);
        $events->attach(ViewEvent::EVENT_RESPONSE, array($this, 'attachPDFtransformer'), 10);
    }
public function attach(EventManagerInterface $events)
    {
        $events->attach(ViewEvent::EVENT_RENDERER_POST, array($this, 'cleanLayout'), 1);
        $events->attach(ViewEvent::EVENT_RESPONSE, array($this, 'attachPDFtransformer'), 10);
    }
hook into the rendering for transformation of HTML to PDF
@param \Zend\EventManager\EventManagerInterface $events