protected function buildPermissionField($groupField, $memberField, $groups, $members) {
		return FieldGroup::create(
			ListboxField::create($groupField, false, $groups)
				->setMultiple(true)
				->setAttribute('data-placeholder', 'Groups')
				->setAttribute('placeholder', 'Groups')
				->setAttribute('style', 'width: 400px;'),

			ListboxField::create($memberField, false, $members)
				->setMultiple(true)
				->setAttribute('data-placeholder', 'Members')
				->setAttribute('placeholder', 'Members')
				->setAttribute('style', 'width: 400px;')
		);
	}