I am using Phpmaker from a number of years, now feel comfortable and familiar with Phpmaker code. I expecting E-commerce/Shopping cart like code generation with Phpmaker in future version.
Shopping Cart is actually can be implemented very easy and quick in the latest version of PHPMaker.
You just only need to write a few lines of code in Page_Foot in order to create the Cart that located on Navbar.
In addition, you may just define/create your own APIs in Api_Action server event to process data in server side.
You may create a custom button for Add to Cart functionality for each record in List Page by using ListOptions_Load and ListOptions_Rendered server event.
You may also create custom button for the same functionality in View Page by using Page_Render server event.
You may then call that API from Startup Script section based on the related event in client side, such as when a Product is added to Shopping Cart, or when an item is removed from the Shopping Cart, or even when the Shopping Cart is emptied by end-users.
You may use multi-dimensional session variable to store some information in that Shopping Cart.
Just try it by yourself, then you will know how PHPMaker has already provided such a beautiful web application framework for you to do all those kind of things above easily and quickly.