I have another case in same topic : calculating price in Ionic.
You can take a look at this codepen : http://codepen.io/harked/pen/gpvdNK
There is initial price worth: $10.00 in the total price.
When user click on (+) button to add item, i.e : LAKSA (price $4.5), the price will be updated to : $14.50 (and the button will be change to (-) minus with red background).
and then When user add BURGER (price $2.5), the price will be updated to : $17.00.
then, when user click on the LAKSA again, the price will be decrease to $12.5.
and so on … that’s happen with the all item.
I’ve found another code here : http://codepen.io/harked/pen/KpQrMW
which is looks like my case. But i get stuck on how to implement this with my case.
Do you have any clue/advice, @bengtler?