For the last 2 days I've been trying to make my single-file document into a package, but I can't get it to work. In the documentation it states the preferred way is to use NSFileWrapper. I've tried it but it's just such a unintuitive way of handling files.
I guess to update a file I need to delete the file wrapper from it's directory, create a completely new one and add it again to the directory. I haven't found anything that explicitly states it, but I guess I should update the file only when fileWrapperOfType:error: is called.
As NSFileWrapper keeps everything (at least once loaded) in memory, this means that I'll have the old version and the new version at the same time until the user (or autosave) saves the file.
It seems like NSFileWrapper shouldn't be used for big files, but I think it's better if all the files that are needed by the document are inside the package(can be copied to another Mac/iPhone/iPad without errors) and I don't want to limit the user on how many/how big the files can be.
When using a manual URL-based saving mechanism, I end up getting corrupt packages, as the destination directory is always a temporary one, and I couldn't find any information on how to merge them. Every time I manually save the document without any changes, an error occurs, as I don't write anything to the temporary directory. But I don't see a reason in writing/linking everything to the temporary directory, only for it to be copied/'un'-linked back to its destination.
As I can't seem to find the right answer, what is the best-practice for saving and restoring big packages with many/big files in them?
