Add and Reduce quantity directly with button + -

[lianix]

Hi.

I've a question about + and - buttons.

 

I've followed this article, https://mypresta.eu/en/art/prestashop-16/quantity-product-list.html,  and set succeffully a quantity field in product list.

So if the user set 10, the buy button add 10 quantity.

 

Now, my question is, ther is a way to set a negative value tu reduce in cart the quantity?

 

 

And the second step is this:

 

I'de like that the user can use + and - button to add and reduce quantity directly in the cartblock or in the product_list.

 

I've tried many times but i don't find the solution.

 

 

Thanks.