Ruby on Rails Sunday, March 5, 2017

You're getting no method error "qty" because @product is not set in your controller action.  So you're essentially trying to subtract @taken from something that is NIL.

You need to see @product as an instance variable in your specific controller method and this should work out for you.


On Mar 5, 2017, at 12:23 PM, Joe Guerra <> wrote:

ok, here's my method...

def calc_remaining
@taken = Cart.where('product_id' => @product).count

@remaining = @product.qty - @taken

but when I call it from my add to cart method, @product.qty is undefined method `qty' for nil:NilClass.

On Thursday, March 2, 2017 at 11:07:06 AM UTC-5, Joe Guerra wrote:
In my show method for my products controller I've got a variable that track qty ( @remaining ).

Can I access this variable from another method within the same controller?


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