I realize that the answer may be in using Dynamic Pages and Datasets, which I haven't yet gotten a good understanding of yet.
I prefer dealing with my collections thru the wix-data.insert(), update(), etc. Already have a member registration that registers subscribers in several different categories to our business.
BUT .. we offer several sets/categories of products to our customers that I want to offer on the same order page, employing multiple lists in pulldowns, the PRIMARY list of which is the CATEGORY of products. Based on the selection of that PRIMARY pulldown: Produce, Meat, Dairy, Bakery, Condiments, etc. I need to offer the full list of products in EACH category in 2 OTHER pulldowns, ONE of which represents their order (for produce) and displays the DEFAULT order for the week, and the OTHER dropdown displays a list of OPTIONS that they can SWAP with items on their Order/List/Dropdown, or ADD outright to their ORDER list.
You DON'T have to understand the details of the movement of products, ONLY that I need to be able to completely refresh and redisplay an entirely NEW list in ONE of the dropdowns (the OPTIONS list), and enable ADDING or REMOVING single items at a time from the OTHER dropdown (their ORDER list), all based on the CATEGORY selection dropdown AND/OR multiple buttons that enable SWAPPING or ADDING or REMOVING items from the order list.
I'm HOPING there is a way to simply change ANY or ALL of the options to any dropdown and refresh/redisplay the NEW list, WITHOUT having to refresh the whole page (which I THINK I can figure out, but only by jumping thru a bunch of hoops, and it would be WAY clunky for the user experience.
If you can help me with a way other than using datasets and Dynamic Pages, I'd be very appreciative.
If I Dataset.refresh() actually re-displays the Dropdown it is attached to, that would be OK (it isn't obvious to me.) I'm thinking that I could build/fill a new dataset for each category selected and refresh it into the OPTIONS Dropdown, and the ORDERS dropdown could be a dataset initialized with the default Produce and refreshed w/each item add/swapped into it.