Core Data & Xcode 11: Please switch to using “NSSecureUnarchiveFromData” or a subclass of NSSecureUnarchiveFromDataTransformer

Swift 5.4.2

This worked for me.

EDIT Link to the article is here.

• Click on the .xcdatamodeld file in the project navigator
• Click on the
  Entity that has a Transformable Attribute
• Click on the Transformable Attribute
• Click the ‘Show Data Model Inspector’ icon
• Enter ‘NSSecureUnarchiveFromDataTransformer’
  in the Transformer field – EDIT Make this ‘NSSecureUnarchiveFromData’ as of Swift 5.5.2.

Your warnings/errors should go away. If not, try cleaning your build folder and rebuild.