Cocoa, error when restoring document

When trying to restore a version of a doc开发者_开发问答ument in my document based application, I get an error:

kCGErrorFailure: CGSDisplayID: App trying to enumerate [0 to CGSGetNumberOfDisplays()] instead of using CGSGetDisplayList(). Compensating...

kCGErrorFailure: Set a breakpoint @ CGErrorBreakpoint() to catch errors as they are logged.

and the document remains unchanged. Also, when this happens, I get a message as soon as I start editing the document telling me:

The document [...] could not be autosaved. The file has been changed by another application.

I think these two problems may be related.

I don't know what to do or "check" because versions just works without any implementation needed; I'm actually confused, because Apple says that I just need to enable autosave in order to restore/revert using versions. Does anyone know what can be causing that error?

Thanks.

I've ran into all of your issues, causing me much pain.

I've gotten that error message regarding kCGErrorFailure... before as well when browsing versions. I've just ignored it mostly as it seems harmless to me. TextEdit seems to spit out this message as well. (Looks like an Apple bug)

For the "document remains unchanged", check here: Restoring from versions browser on OSX lion not working... ideas? (in short, your code for updating your document's UI is probably not being called for the document that is being reverted) (Looks undocumented to me)

For autosaving issues, check here: http://www.cocoabuilder.com/archive/cocoa/306217-how-to-implement-autosaving-browsing-versions-reverting-to-last-saved-in-lion.html (in short, use the file wrapper methods instead for reading and writing). (Looks like an Apple bug)

As well as returning YES to autosavesInPlace: your document needs to at least call updateChangeCount: passing NSChangeDone whenever it changes, so that it "knows" that there are changes to be autosaved.