I have a program that exports PDF, TIFF, and PNG files so I followed Apple’s Sketch example when declaring types in my Info.plist file:

CFBundleTypeExtensions foo CFBundleTypeName MyDocumentFileType CFBundleTypeRole Editor NSDocumentClass MyDocument NSExportableAs NSPDFPboardType NSTIFFPboardType MyPNGFileType CFBundleTypeExtensions pdf CFBundleTypeName NSPDFPboardType CFBundleTypeRole None CFBundleTypeExtensions tiff tif CFBundleTypeName NSTIFFPboardType CFBundleTypeRole None CFBundleTypeExtensions png CFBundleTypeName MyPNGFileType CFBundleTypeRole None

Unfortunately, this has an unexpected consequence. Calls to -[NSDocumentController fileExtensionsFromType:] with @”NSPDFPboardType” or @”NSTIFFPboardType” return nil but calling the method with @”MyPNGFileType” still works as expected.

So why is this happening? Thanks!