public function getPluginManager()
    {
        if (null === $this->plugins) {
            $this->setPluginManager(new Navigation\PluginManager());
        }
        return $this->plugins;
    }
public function getPluginManager()
    {
        if (null === $this->plugins) {
            $this->setPluginManager(new Navigation\PluginManager());
        }
        return $this->plugins;
    }
public function getPluginManager ( ) { if ( null === $ this -> plugins ) { $ this -> setPluginManager ( new Navigation \ PluginManager ( ) ) ; } return $ this -> plugins ; }
Retrieve plugin loader for navigation helpers

Lazy-loads an instance of Navigation\HelperLoader if none currently
registered.

@return Navigation\PluginManager
Retrieve plugin loader for navigation helpers