Beginning Core Data - Part 3: Managed Object | Ray Wenderlich

Learn how to use managed object subclasses to easily manipulate your data.

This is a companion discussion topic for the original entry at

Users need to change the Codegen of the Entity to Manual/None otherwise when you create the NSManagedObjectSubclass, it will create it twice, one in your project folder and another in derived data.


Thanks for sharing the tip @rajee.afterhoursdev!

Bug report, In the challenge project you may :

  • Allow app to access to photo: add 'Privacy - Photo Library Usage Description" to info.pList

  • pictureImageView outlet is missing: You have to connect it from the storyboard to TargetCollectionViewCell class

Anyway great course Luke :grinning:

I wish I read this sooner! I found the same thing the hard way. Then I also found out that you need to do this for every entity in your data model!!! If you don’t, you will get an error code 1, which is ambiguous at best.

I downloaded and run .
It’s good on my macbook.
But when i run on on my iPhone 6, iOS 10.0.1 I got error "dyld: Library not loaded: @rpath/libswiftCore.dylib
Referenced from: /var/containers/Bundle/Application/C9380543-715A-4274-9DFE-9414393149DF/
Reason: no suitable image found. Did find:
/private/var/containers/Bundle/Application/C9380543-715A-4274-9DFE-9414393149DF/ code signing blocked mmap() of ‘/private/var/containers/Bundle/Application/C9380543-715A-4274-9DFE-9414393149DF/’
(lldb) ". Please help me to solve this

@luke_parham Can you please help with this when you get a chance? Thank you - much appreciated! :]