Следующий и предыдущий товар в админке - Разработки и улучшения

        JToolBarHelper::customX("product_prev","back","back",_JSHOP_PREV, false);
        JToolBarHelper::customX("product_next","forward","forward",_JSHOP_NEXT, false);

    function product_next(){
        $products = &$this->getModel("products");
        $rows = $products->getAllProducts(Array("publish"=>1));
        $total = Count($rows);
        $product_id = JRequest::getInt('product_id');
        $Next = $product_id;
        foreach($rows as $Key=>$row){
        	If ($Key < $total){
        		If ($row->product_id == $product_id){
        			$Next = $rows[$Key + 1]->product_id;
        			Break;
        		}
        	}
        }
        If (!$Next) $Next = 1;
        $this->setRedirect("index.php?option=com_jshopping&controller=products&task=edit&product_id=".$Next);
    }
    function product_prev(){
        $products = &$this->getModel("products");
        $rows = $products->getAllProducts(Array("publish"=>1));
        $total = Count($rows);
        $product_id = JRequest::getInt('product_id');
        $Prev = $product_id;
        foreach($rows as $Key=>$row){
        	If ($Key < $total){
        		If ($row->product_id == $product_id){
        			$Prev = $rows[$Key - 1]->product_id;
        			Break;
        		}
        	}
        }
        If (!$Prev) $Prev = 1;
        $this->setRedirect("index.php?option=com_jshopping&controller=products&task=edit&product_id=".$Prev);
    }

define('_JSHOP_NEXT','Следующий товар');
define('_JSHOP_PREV','Предыдущий товар');

		$JToolBar = JToolBar::getInstance('toolbar');
		$products = JTable::getInstance("Product", "JShop");
		$rows = $products->getAllProducts(array(), "product_id", "ASC");
		$total = count($rows) - 1;
		$product_id = JFactory::getApplication()->input->getInt('product_id', 0);
		$prev = false;
		$next = false;
		foreach($rows as $key=>$row){
			if ($row->product_id == $product_id){
				if ($key < $total){
					$next = true;
				}
				break;
			}
			$prev = true;
		}
		if ($prev) {
			$JToolBar->appendButton('Standard', 'back', "Предыдущий товар", "product_prev", false);
		}
		if ($next){
			$JToolBar->appendButton('Standard', 'forward', "Следующий товар", "product_next", false);
		}

	function product_next(){
		$products = JTable::getInstance("Product", "JShop");
		$rows = $products->getAllProducts(array(), "product_id", "ASC");
		$total = count($rows);
		$product_id = JFactory::getApplication()->input->getInt('product_id', 0);
		$next = $product_id;
		foreach($rows as $key=>$row){
			if ($key < $total){
				if ($row->product_id == $product_id){
					$next = $rows[$key + 1]->product_id;
					break;
				}
			}
		}
		if (!$next) $next = 1;
		$this->setRedirect("index.php?option=com_jshopping&controller=products&task=edit&product_id=".$next);
	}
	function product_prev(){
		$products = JTable::getInstance("Product", "JShop");
		$rows = $products->getAllProducts(array(), "product_id", "ASC");
		$total = count($rows);
		$product_id = JFactory::getApplication()->input->getInt('product_id', 0);
		$prev = $product_id;
		foreach($rows as $key=>$row){
			if ($key < $total){
				if ($row->product_id == $product_id){
					$prev = $rows[$key - 1]->product_id;
					break;
				}
			}
		}
		if (!$prev) $prev = 1;
		$this->setRedirect("index.php?option=com_jshopping&controller=products&task=edit&product_id=".$prev);
	}