'Varchar', 'Surname' => 'Varchar' ); private static $has_one = array( 'Group' => PeopleGroup::class ); private static $many_many = array( 'Categories' => Category::class, 'FavouriteGroups' => PeopleGroup::class ); private static $many_many_extraFields = array( 'Categories' => array( 'IsPublished' => 'Boolean', 'PublishedBy' => 'Varchar' ) ); private static $default_sort = '"FirstName"'; public function getCMSFields() { $fields = parent::getCMSFields(); // TODO No longer necessary once FormScaffolder uses GridField $fields->replaceField('Categories', GridField::create('Categories', 'Categories', $this->Categories(), GridFieldConfig_RelationEditor::create() ) ); $fields->replaceField('FavouriteGroups', GridField::create('FavouriteGroups', 'Favourite Groups', $this->FavouriteGroups(), GridFieldConfig_RelationEditor::create() ) ); return $fields; } public function getCMSValidator() { return new RequiredFields(array( 'FirstName', 'Surname' )); } }