ImageGroup::model PHP Method

    public static function model($className = __CLASS__)
    {
        return parent::model($className);
    }

 public function actionDelete($id)
 {
     if (ImageGroup::model()->findByPk($id)->delete()) {
         Yii::app()->ajax->success(Yii::t('StoreModule.store', 'The group is successfully deleted'));
     }
     Yii::app()->ajax->error(Yii::t('StoreModule.store', 'Failed to delete group'));
 }