OrderModel #4
Description
Conceptually there needs to be an OrderModel with the details of the order. This would include which dishes are being ordered, quantities, and add-on choices for the dish.
This will affect some aspect of the views. For example, the DishAddOnView has a boolean property isSelected that you track internally in the view and update when the button is selected/deselected. This state should be stored inside a model. Depending on how you want to design the model, you might have a "selected" property in the DishAddOn model and just bind on that.
If you find yourself adding state variables inside a View class (other than just to help with determining if it is in-sync with the model), then it is an indication that the model needs to be adjusted to store that state instead.