public function add_related_objects() {

		PodsField_Pick::$related_objects['table'] = array(
			'label' => __( 'Database Tables', 'pods' ),
			'group' => __( 'Advanced Objects', 'pods' ),
		);

		if ( is_multisite() ) {
			PodsField_Pick::$related_objects['site'] = array(
				'label' => __( 'Multisite Sites', 'pods' ),
				'group' => __( 'Advanced Objects', 'pods' ),
			);

			PodsField_Pick::$related_objects['network'] = array(
				'label' => __( 'Multisite Networks', 'pods' ),
				'group' => __( 'Advanced Objects', 'pods' ),
			);
		}

		PodsField_Pick::$related_objects['theme'] = array(
			'label'         => __( 'Themes', 'pods' ),
			'group'         => __( 'Advanced Objects', 'pods' ),
			'simple'        => true,
			'data_callback' => array( $this, 'data_themes' ),
		);

		PodsField_Pick::$related_objects['page-template'] = array(
			'label'         => __( 'Page Templates', 'pods' ),
			'group'         => __( 'Advanced Objects', 'pods' ),
			'simple'        => true,
			'data_callback' => array( $this, 'data_page_templates' ),
		);

		PodsField_Pick::$related_objects['sidebar'] = array(
			'label'         => __( 'Sidebars', 'pods' ),
			'group'         => __( 'Advanced Objects', 'pods' ),
			'simple'        => true,
			'data_callback' => array( $this, 'data_sidebars' ),
		);

		PodsField_Pick::$related_objects['post-types'] = array(
			'label'         => __( 'Post Type Objects', 'pods' ),
			'group'         => __( 'Advanced Objects', 'pods' ),
			'simple'        => true,
			'data_callback' => array( $this, 'data_post_types' ),
		);

		PodsField_Pick::$related_objects['taxonomies'] = array(
			'label'         => __( 'Taxonomy Objects', 'pods' ),
			'group'         => __( 'Advanced Objects', 'pods' ),
			'simple'        => true,
			'data_callback' => array( $this, 'data_taxonomies' ),
		);
	}