Good morning, I’ve got a scenario where I need to prompt the user during reading of a document in my OS X document-based application. There have been some minor changes to the format of my document files, and I need to support opening documents saved in the old format and prompting the user to convert the file to the new format. The old and new formats use the same file extension/type info, so I need to actually open the file and check the internals to determine if it is the old format or the new.
My document reading happens in readFromData:ofType:error:. In that method I’ve added code which determines the format and, if it’s the old format, creates and displays an NSAlert to ask the user if they want to update the document in-place or create a copy. This seems to work in initial testing — the alert displays — but I get a message in the console telling me that “NSAlert is being used from a background thread, which is not safe. This is probably going to crash sometimes. …” Presumably this is because I have overridden +canConcurrentlyReadDocumentsOfType: to return YES for my documents, resulting in document reading happening on a background thread. Changing +canConcurrentlyReadDocumentsOfType: to return NO makes the warning message go away. My question is, is there a more appropriate or “correct” place or pattern for me to do this checking of the document format and prompting the user, instead of in readFromData:…? Or am I doing this correctly, and I just can’t read documents concurrently because I may need to prompt the user during reading of a document? Thanks! _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
