Sorting arrows in stock management

[jokerstar]

Hello,

I would like ask you how can I add sorting arrows into stock managemet in back office? 

path:   back office/stock/stock management

 

I think it will be something in php but its difficult for me.

 

Please check attachment.

 

 

[vekia]

/controllers/admin/AdminStockManagement.php

there is a code like:
 

	public function __construct()
	{
		$this->context = Context::getContext();
		$this->table = 'product';
		$this->className = 'Product';
		$this->lang = true;
		$this->multishop_context = Shop::CONTEXT_ALL;

		$this->fields_list = array(
			'reference' => array(
				'title' => $this->l('Product reference'),
				'align' => 'center',
				'filter_key' => 'a!reference',
				'width' => 200
			),
			'ean13' => array(
				'title' => $this->l('EAN13'),
				'align' => 'center',
				'filter_key' => 'a!ean13',
				'width' => 100
			),
			'upc' => array(
				'title' => $this->l('UPC'),
				'align' => 'center',
				'filter_key' => 'a!upc',
				'width' => 100
			),
			'name' => array(
				'title' => $this->l('Name'),
			),
			'stock' => array(
				'title' => $this->l('Quantity'),
				'hint' => $this->l('Quantitity total for all warehouses.'),
				'width' => 100,
				'orderby' => false,
				'filter' => false,
				'search' => false,
			),
		);

from this part:
 

			'stock' => array(
				'title' => $this->l('Quantity'),
				'hint' => $this->l('Quantitity total for all warehouses.'),
				'width' => 100,
				'orderby' => false,
				'filter' => false,
				'search' => false,
			),

remove

'orderby' => false,

effect:

[jokerstar]

Hello Vekia thanks for quick answer. I edit what you wrote but it added arrows, but if I click on them it doesnt work, it returns one line with zero. 

[vekia]

add there also this:

'filter_key' => 'a!quantity',

[jokerstar]

add there also this:

'filter_key' => 'a!quantity',

now it reloads page, but dont sort. I tried both arrows but nothing happens

[jokerstar]

Vekia do you have any idea? It looks like that this arrows dont use quantity value, but it is only my guess