Expect to increase this event, sometimes need to do some dynamic load/unload, for example, the album will have a lot of pictures, load all the display will waste a lot of memory.
The desired function is that when the parent object scrolls, the child object is out of visual range, the child object sends OUT_EVENT, and when scrolling from outside the window to inside the window, the child object sends IN_EVENT, and the child object implements load/unload in the OUT_EVENT/IN_EVENT event.
Currently, LV_EVENT_SCROLL is used to implement this. Generally, LV_EVENT_SCROLL_XXX events are very frequent, and scrolling requires traversing all child objects to see if they are out of range, resulting in poor performance.
At the same time, it is hoped that the decoded Image should remain in the cache of the image object until the object is deleted, of course, it should be configurable, so that with the above mentioned functions, IN_EVENT/OUT_EVENT events to create/delete
Maybe LVGL9 already has a better implementation, I just haven’t found it yet