How to migrate the old plist and Core Data store to an updated app (iPhone)

Question

Hi

I was just wondering, I have an app that relies on Core Data for saving user inputted data and a plist file for keeping track of user settings etc.

What happens when I, as a developer, put a new version in the store and a user downloads the update? or a new user downloads the app? How will I make sure their data and settings are not overwritten? .. or a new model is build if the user is new.

It would surprise me if Apple did not have some way of dealing with this, I just couldn't find it in any "Programming Guide" and I bet it is something I will have to make arrangements for, before putting it in the store:)

I have versioning and I am using lightweight migration to keep my Core Data model in sync, development-wise, but besides from that I have no idea what happens when an App updates?

Hope some experienced developers could point me in the right direction:)

Answer 1

When your app downloaded and installed 'over' an existing, older copy, this is done 'in place'. The user's data files and preferences are left untouched. Assuming you've handled your Core Data migration properly, you'll be all set.