appending a frame to item frame

[cyxui]

I wonder how to add a frame (panel, box donno the exact name) to the item frame.

For example when my mouse points to an Item, a frame is going to show up to display the detail information such as the value, larger picture and such. I want to be able to append some information on the bottom part. Which means I would also need to be able to know the information about the current item, ideally the item link of it.

Either XML/Lua implementation would be fine.

Thanks

[merlight]

The control name is ItemTooltip. Its methods are listed in official ZOS API documentation, it's a little tedious to make it work with items from different places, as there are distinct methods for setting an item from bag/bank/mail attachment/store/link, etc.

There are multiple add-ons working with that already, you can check how they do it.
I've been using two:
Harven's Trait And Style (doesn't add to the bottom, but the idea is the same)
Sous Chef (currently unmaintained, I think, but Master Recipe or how it's called probably has a similar feature)

Some I don't use but remember they add/added something to tooltips: Inventory Insight,
Crafting Materials Level Display, various guild store price trackers...