Swift 3 Entity Master Data: Using an Undeclared Type

Question

Use of undeclared type 'Transcription'

I follow this simple Core Data tutorial in Swift 3 ( https://learnappdevelopment.com/uncategorized/how-to-use-core-data-in-ios-10-swift-3/ )

and I get the above error in the line: let fetchRequest: NSFetchRequest<Transcription> = Transcription.fetchRequest()

I double checked, and Entity "Transcription" is spelled correctly in my .xcdatamodeld file

The tutorial was developed for Swift 3, but there was another change since it was released that I fixed, so I assume that some changes in Swift over the last 2 months caused this error.

I'm new to Core Data, so I don't know how to debug this. I would be very grateful for the decision!

Answer 1

Remember to import CoreData to your subclass

Answer 2

Select the data model, go to the editor -> Subclass NSManagedObject ...

This solved the error

Answer 3

I was worried about the same error I used for Xcode 8.2.1. I cleaned the project, closed Xcode and reopened it, the error was fixed after the build.

Answer 4

Perhaps this was due to the fact that Xcode cannot determine the .xcdatamodel path , you can see a related error while cleaning up the project. This error occurred with one of my projects when changing the name of .xcdatamodel .

The solution includes the following:

• go to Product → Clean (Shift-Cmd-K)
• if the error persists
  • Ctrl-click (right click) problematic .xcdatamodel → Show in Finder
  • Drag .xcdatamodel to import into the project, a new entry must be created
  • Delete the previous .xcdatamodel entry.
• Build (Cmd-B) to confirm the fix

Answer 5

Using Xcode version 8.2 beta (8C30a), when I add or modify an object, I get the same error. In the data model inspector, change the Codegen parameter to Manual / None, as if I was going to create dynamic classes myself. Save and then go back to category / Extension, and it seemed to work. (I also tried cleaning the project with Option-Clean by restarting Xcode, but I could easily play it back.) I hope the beta beta beta beta 4.0 update will be fixed.

Answer 6

No. 1) Create a subclass, go to the editor → Create a subclass of NSManagedObject ... Then replace the subclass files in the folder of the same project:

2) then delete the files in the derived data - in Xcode -> Settings:

3) and then remove the link to the old NSManagedObject Subclass files, because they automatically create the system:

Answer 7

I had to remove my entity, which gave me an error, in your Transcription case, from my .xcdatamodeld file, and then add it manually again.