Maintained by the library after calling showItem so the object knows which data index it currently has.
It may be -1, indicating nothing is currently loaded (or a load failed, and the current data is potentially inconsistent).
Inside the call to showItem, currentIndexLoaded is the old index, and the argument to showItem is the new index. You might use that to save state to the right place as needed before you overwrite it with the new item.
Maintained by the library after calling showItem so the object knows which data index it currently has.
It may be -1, indicating nothing is currently loaded (or a load failed, and the current data is potentially inconsistent).
Inside the call to showItem, currentIndexLoaded is the old index, and the argument to showItem is the new index. You might use that to save state to the right place as needed before you overwrite it with the new item.