Complex Product Combinations

[spardbc]

Hello

 

My store is a cafeteria. The price of each product varies depending on grammage, quantity and/or number of servings.

The client must be able to choose the weight (kg) or a number of servings and, according to his choice, price and other value (grammage or number of servings) must change automatically.

I made the combinations, but I fail to do the update thing.

 

E.g:

 

I have two dropboxes, one displays the grammage, the other number of servings / per grammage.

For instance, a cake has 1,5kg = 15 servings

 

When I change the weight, number of servings should be updated automatically and vice versa, when I change the number of servings the grammage must update accordingly. 

 

Right now only the price is updating.

 

Here is an example of what I'm trying to get:

 

http://www.cofetariaarmand.ro/torturi-cu-ciocolata/tort-trois-mousse-458.html

 

Does anyone know how to do this?

 

Thank you

[Nati Mask]

If there is a fixed mathematical formula to describe the gram units with the servings and vice versa, so you need only one "product attribute" to exist,

I mean the Back Office has to know only about one of them, and the pricing will set according to it.

 

Then in the front side you can bind some javascript event to make sure that any change to the one drop down selector (The real "gram" selector) will set the other one (Servings) and vice versa.

 

Indeed this will involve some programming...