The very only LVGL example of custom theme was the Printer Demo, but it was not ported to LVGL v8.
I have already developed projects using LVGL v7 and now I’m trying to develop with LVGL v8 (current version), but I am struggling with the very start, creating a theme.
A lot has changed in this subject from LVGL v7 to LVGL v8, but I couldn’t find any proper documentation explaining how to port something like that project to LVGL v8. I am wasting a lot of time studying the library source code instead of programming and about to consider keep developing with LVGL v7.
In one of my recent experience, with a project that was started with v7 we decide to rewrite almost from scratch the things with lvgl v8. It was easier than try to understand how to exactly map v7 setup to v8.