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iOS

Posted by Kieran Robinson
Kieran Robinson
9,411 Points

Removing an attributes value from core data

Hi! I want to know how to remove a specific attribute from a coreDataStack. for example if i have an attribute in my coreDataStack (the entity is called: entityExample) that is called photoData.

I want to allow the user to click a delete button on the image (a small cross overlay) and it removes the imageData attribute's value from the coreDataStack.

here is my code within the buttonPressed method;

[[coreDataStack managedObjectContext]deleteObject:_entityExample.photoData];
[coreDataStack saveContext];

however, i get an error of incompatible pointer types as 'deleteObject:_entityExample.imageData];' is should have a managedObjectContext value not a NSData value.

Any help is much appreciated

Kieran Robinson
Kieran Robinson
9,411 Points

Ash Furrow, Sam Soffes, Amit Bijlani, Ben Jakuben

1 Answer

Amit Bijlani
STAFF
Amit Bijlani
Treehouse Guest Teacher
Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

The deleteObject method deletes a managed object from the context and not an attribute. If you want update/change the value of an attribute then simply assign it a value and then save the context.

_entityExample.photoData = nil;
[coreDataStack saveContext];