chill-bundles/docs/source/development/user-interface/widgets/ChillMainConfiguration.php

<?php

/**
 * Chill is a software for social workers
 *
 * For the full copyright and license information, please view
 * the LICENSE file that was distributed with this source code.
 */

namespace Chill\MainBundle\DependencyInjection;

   use Chill\MainBundle\DependencyInjection\Widget\AddWidgetConfigurationTrait;
   use Symfony\Component\Config\Definition\Builder\TreeBuilder;
   use Symfony\Component\Config\Definition\ConfigurationInterface;
   use Symfony\Component\DependencyInjection\ContainerBuilder;

   /**
    * Configure the main bundle.
    */
   class Configuration implements ConfigurationInterface
   {
       use AddWidgetConfigurationTrait;

       /**
        * @var ContainerBuilder
        */
       private $containerBuilder;

       public function __construct(
           array $widgetFactories = [],
           ContainerBuilder $containerBuilder
       ) {
           // we register here widget factories (see below)
           $this->setWidgetFactories($widgetFactories);
           // we will need the container builder later...
           $this->containerBuilder = $containerBuilder;
       }

       public function getConfigTreeBuilder()
       {
           $treeBuilder = new TreeBuilder();
           $rootNode = $treeBuilder->root('chill_main');

           $rootNode
               ->children()

                   // ...
               ->arrayNode('widgets')
               ->canBeDisabled()
               ->children()
                            // we declare here all configuration for homepage place
               ->append($this->addWidgetsConfiguration('homepage', $this->containerBuilder))
               ->end() // end of widgets/children
               ->end() // end of widgets
               ->end() // end of root/children
               ->end() // end of root
;

           return $treeBuilder;
       }
   }