Question

I have a data model with an entity called Image. This will be used to store images.

Previously I had the image as an attribute of a specific entity.

I set up the transformable stuff and it all worked.

However, now I’ve moved it into a separate entity I keep getting errors.

So… This is the Image.m file contents.

#import "Image.h"
#import "Person.h"

@implementation ImageToDataTransformer


+ (BOOL)allowsReverseTransformation {
    return YES;
}

+ (Class)transformedValueClass {
    return [NSData class];
}


- (id)transformedValue:(id)value {
    NSData *data = UIImagePNGRepresentation(value);
    return data;
}


- (id)reverseTransformedValue:(id)value {
    return [[UIImage alloc] initWithData:value];
}

@end

@implementation Image

@dynamic image;
@dynamic createdDate;
@dynamic person;

@end

When I save it it doesn’t complain when I create it it doesn’t complain, I can even see it in the Person entity as an object.

(Person *) $0 = 0x1002dec0 <Person: 0x1002dec0> (entity: Person; id: 0x4f8f30 <x-coredata://2800C028-8745-45FE-854B-5783FF3FC173/Person/p6> ; data: {
    avatar = "0x1007e540 <x-coredata://2800C028-8745-45FE-854B-5783FF3FC173/Image/p1>";
    createdDate = nil;
    email = nil;
    firstname = Blah;
    id = "1234567890987654321234567890";
    lastName = Blah;
    updatedDate = nil;
})

The avatar attribute is a relationship to an Image entity (one to one).

But if I try to access any attribute of the image I get this…

-[_NSObjectID_64_2 createdDate]: unrecognized selector sent to instance 0x1007e540
-[_NSObjectID_64_2 image]: unrecognized selector sent to instance 0x1007e540

etc etc…

Code that generates error…

NSFetchRequest *request = [NSFetchRequest fetchRequestForEntityName:@"Person"];

[request setPredicate... blah];
NSArray *results = [context executeFetchRequest...];

Person *person = [results objectAtINdex:0];

NSLog(@"%@", person.firstName); //this works fine.
NSLog(@"%@", person.avatar.createdDate); //this crashes.

Tried removing the image attribute and still getting the same problem.

Answer 1

Well, that was completely bizarre.

I deleted the entity and re-added it… still the same problem.

I deleted it again and added an entity called “StoredImage” instead of “Image” and it worked fine with no problems at all.

Thanks for all the help though.