src/Detail/Mail/MtMail/OverrideHeadersComposerPlugin.php
public function attach(EventManagerInterface $events)
    {
        $this->listeners[] = $events->attach(
            ComposerEvent::EVENT_HEADERS_POST,
            array($this, 'injectOverrideHeaders'),
            -100 // The priority needs to be lower than the other plugins
        );
    }
public function attach(EventManagerInterface $events)
    {
        $this->listeners[] = $events->attach(
            ComposerEvent::EVENT_HEADERS_POST,
            array($this, 'injectOverrideHeaders'),
            -100 // The priority needs to be lower than the other plugins
        );
    }
public function attach ( EventManagerInterface $ events ) { $ this -> listeners [ ] = $ events -> attach ( ComposerEvent :: EVENT_HEADERS_POST , array ( $ this , 'injectOverrideHeaders' ) , - 100 // The priority needs to be lower than the other plugins ) ; }
Attach listener.

@param EventManagerInterface $events
Attach listener .