If you’ve ever wondered how to use Apple’s Publication Subscription Framework in a sandboxed application environment, just read this post written by Sasmito Adibowo from Basil Salad Software.

Update Jan 5, 2012:

There are still some issues with using PubSub in a sandboxed environment. It seems that PubSub won’t post all notifications and won’t call all delegate methods it should when being sandboxed. The PSFeed notifications don’t seem to work if they contain a userinfo dictionary and the same is true for those of PSClient’s delegate methods which contain more information than just the feed object responsible for the delegate call.

This means that the delegate methods feedDidBeginRefresh: and feedDidEndRefresh: will be called but not didAddEntries:, didRemoveEntriesWithIdentifiers:, didUpdateEntries: and so on. This is not really painful as it is possible to calculate what changes occured to a feed by directly accessing the PSFeed object’s properties, but it is still a nuisance.

Update Jan 20, 2012:

Apple has confirmed this to be a bug.