public function __construct(App $app)
 {
     parent::__construct($app);
     $this->tableProduct = $this->getModel()->getTableName();
     $this->tableSku = Sku::getTableName();
     $this->tableSkuImages = Sku\Image::getTableName();
     $this->tableSupplier = Supplier::getTableName();
     $this->tableCategory = Category::getTableName();
     $this->tableProductCategory = ProductCategory::getTableName();
 }