Hi,

1 - can you please remind me how you clear the cart? It should be possible to make that more targetted so that it just removes things from a particular category.

I should add however that this doesn't sound very user-friendly. Shouldn't you be looking for a way to hide items from a particular category once someone has purchased from that category? Instead, it looks like you're going to allow them to see the products, allow them to click "add to cart", but then mysteriously the products will get deleted from the cart again? (NB I don't know how else you would do it, but I think you should at least try to find another way)

2 - upgrades: there were free upgrades given to people who purchased the J1.5 version in the 3 months before the J2.5 version came out. Unfortunately due to the amount of effort it took to develop the new version there's no upgrade pricing.

Best regards,
Stephen

Ok, actually that makes more sense than I thought. I thought that you were not going to allow the *new* item to be added, but you mean that the new item will get rid of any old ones in the same category.

Actually I think this may be more difficult than anticipated. Part of the problem is knowing which of the products in the cart is the new one and which is the old one.

The other part of the problem is that Chameleon runs *before* the new product is actually added to the cart. The POST or AJAX request will have been received by Joomla, then Chameleon gets run, but at this point if Chameleon looks at the cart it will only have products in it that were added at an earlier time, NOT yet the new product that the user is adding. Also, the VirtueMart system itself has not been initialised at the time Chameleon is running, so you don't get access to the $ps_cart object like you do later.

I suppose it might be able to be done this way:
1 - detect if the POST/AJAX request is for adding a new product to the cart. If so, make a note of its category id
2 - check if there's something in the cart of that category
3 - if so, delete that product from the cart.

The original poster was using MetaMod which runs at a much later stage in the page cycle, when VirtueMart has been initialised. In that case it's easier to work with the cart object since it has been initialised, but by then the new product has been added to the cart and it may be difficult to determine which one to delete. Oh, and by that time most of the page has been generated, so the main component may still show the old item in the cart. So I guess doing this in the MetaMod isn't a great way to go.

Ok, I just looked at the cart data structure a little more closely, with a couple of products in the cart.

Bad news.

Part of the cart data includes the pricing situation for the entire cart. e.g. tax, sales prices, subtotals and the bill total.

If you remove something from the cart, all of this stuff is going to have to be recalculated. It's not just a matter of removing an item from an array, as I had first hoped.

It wouldn't be so bad if the VM system had been initialised by this point, as there may be API you could call to remove a particular item. But as this is not the case, you'd have to code something directly into Chameleon to handle all the pricing and subtotalling, and that's not going to be fun.

I would recommend finding a PHP developer who knows VM to work on this. It's beyond the level of Chameleon help, I am afraid.

Sorry about that,
Stephen