protected function initDefaultButtons()
{
parent::initDefaultButtons();
$this->buttons['custom'] = function ($url, $model) {
$event = new CustomActionEvent(['module' => \Yii::$app->controller->getUniqueId(), 'model' => $model]);
Event::trigger($this, self::EVENT_CUSTOM_ACTION, $event);
return implode(' ', $event->buttons);
};
}
