How to register a custom non-document UTI / file type for OSX to recognize it?

Question

I've read all the tickets about this issue, but I still don't get it right. I have a non-document OSX app (for OSX Lion and MountainLion). I want this app to export and import custom data, associated with a custom file extension ".iobs". Internally, these files are just data archived with [NSKeyedArchiver archivedDataWithRootObject:], and saved onto the disk with the "iobs" extension.

So, my check list is this:

1) Export mechanism: checked. My app create correctly .iobs files. If I run "file <filename.iobs>" in the Terminal, I get "iObserve_exportedItems.iobs: Apple binary property list"

2) Declaration of an exported UTI, checked. As shown in the image below. I did NOT declared a custom Document type, since it I never use NSDocument inside my app, and there is no point. Anyway, I already tried and failed. I've tried also different combinations of "Conforms To" entries, but with no success.

3) Is there any 3rd point??? Do I need to start my app once to let the system know? I just ran it in Debug from Xcode so far, and this has no effect. So I guess my Info.plist is wrong, but I filled it from within Xcode4 interface, so???

Thanks for any help, hint, question, suggestion.

Answer 1

Ok, so apparently, I do have to declare a document type even if I don't specify a document class. See the attached screenshot. Note that leaving only the Document UTI doesn't work. I do need the two (exported UTI and document type). Note also that if I say it conforms to com.apple.binary-property-list, I don't have the right icon.

And for those who wonder, there is nothing to do to "register" a type (and its subsequent changes) apart from launching the app once.