Two extra files were added when creating NSManagedObject subclass

Question

When I created a NSManagedObject subclass for THDiaryEntry Model, it generated two extra files, THDiaryEntry+CoreDataProperties.h and TheDiaryEntry+CoreDataProperties.m. What should I do with these two files?

// // THDiaryEntry+CoreDataProperties.h // Diary

// Choose "Create NSManagedObject Subclass…" from the Core Data editor menu // to delete and recreate this implementation file for your updated model. //

import "THDiaryEntry.h"

NS_ASSUME_NONNULL_BEGIN

@interface THDiaryEntry (CoreDataProperties)

@property (nonatomic) NSTimeInterval date; @property (nullable, nonatomic, retain) NSString *body; @property (nullable, nonatomic, retain) NSData *imageData; @property (nonatomic) int16_t mood; @property (nullable, nonatomic, retain) NSString *location;

@end

NS_ASSUME_NONNULL_END

// // THDiaryEntry+CoreDataProperties.m // Diary // // Choose "Create NSManagedObject Subclass…" from the Core Data editor menu // to delete and recreate this implementation file for your updated model. //

import "THDiaryEntry+CoreDataProperties.h"

@implementation THDiaryEntry (CoreDataProperties)

@dynamic date; @dynamic body; @dynamic imageData; @dynamic mood; @dynamic location;

@end

import <Foundation/Foundation.h>

import <CoreData/CoreData.h>

NS_ASSUME_NONNULL_BEGIN

@interface THDiaryEntry : NSManagedObject

// Insert code here to declare functionality of your managed object subclass

@end

NS_ASSUME_NONNULL_END

import "THDiaryEntry+CoreDataProperties.h"

import <Foundation/Foundation.h>

import <CoreData/CoreData.h>

NS_ASSUME_NONNULL_BEGIN

@interface THDiaryEntry : NSManagedObject

// Insert code here to declare functionality of your managed object subclass

@end

NS_ASSUME_NONNULL_END

import "THDiaryEntry+CoreDataProperties.h"

Answer 1 · 2015-11-07T12:17:26Z

November 7, 2015 12:17pm

Hi Zhuonan.

When creating subclasses out of your Core Data datamodel X-code automatically creates those two extra files and should do, so it not a problem. The first file "THDiaryEntry.h" is where you make your changes if you want to add any. The other file "THDiaryEntry+CoreDataProperties.h" is what Core Data itself manages, so you shall not make any changes in there. The same goes for the "THDiaryEntry.h" and "THDiaryEntry+CoreDataProperties.h" as well. If and when you make some changes to the "THDiaryEntry.h" by file for example, then when you build your project Core Data will update the "THDiaryEntry+CoreDataProperties.h" file to match your changes.

Hope this explanation made sense for you... Keep coding! / Jens

Answer 2 · 2015-10-25T14:47:57Z

October 25, 2015 2:47pm

I have this problem too..

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Jonas Wang

Jonas Wang

Two extra files were added when creating NSManagedObject subclass

import "THDiaryEntry.h"

import "THDiaryEntry+CoreDataProperties.h"

import <Foundation/Foundation.h>

import <CoreData/CoreData.h>

import "THDiaryEntry+CoreDataProperties.h"

import <Foundation/Foundation.h>

import <CoreData/CoreData.h>

import "THDiaryEntry+CoreDataProperties.h"

2 Answers

Jens Hagfeldt

Jens Hagfeldt

Ben Bastow

Ben Bastow