macOS Core Data, adding an object that's related to another object without the UI

[Chirone]

let's say in my data model i have two entities

entity1 can be related to multiple entity2 and entity2 can only be related to one instance of entity1

now.. in the UI i want to make an instance of entity1
all good.. i can do that
entity1 has a string property and i want to split that up and use them to make instances of entity2 (so when entity2 is made it has a copy of that part of the string)

what is the best way to do this?
i thought about sending a notification when the OK button is done creating an instance of entity1, but somehow i don't think that the instance of entity2 will properly be related to entity1 and thus will not be saved out..

any hints?

 

[Chirone]

in the UI i have two panels, one that represents entity1 and the other representing entity2

when entity1 is added i can assign as many entity2s as i want. which is ok, but when entity1 awakes from insert i want it to have some existing entity2s...

so in entity1's awakeFromInsert method i went something like this:

-(void)awakeFromInsert {
	Entity2* anEntity = [[Entity2 alloc] init];
	anEntity.properyOne = @"hello";
	self.containsEntities= [self.containsEntities setByAddingObject: anEntity];
}

but the console printed out this:

2009-05-22 15:17:53.959 CoreDataTestProgram 003[25683:10b] *** -[Entity2 setPropertyOne:]: unrecognized selector sent to instance 0x1bb9f0

uh... what? this tells me that the instance of Entity2 doesn't have the ability to set propertyOne... but... it's there in the code....

what's the proper way to programatically add an entity to the relationship?



nevermind

the answer has been here all the time:

NSManagedObjectContext* managedObjectContext = [self managedObjectContext];
	self.containsEntites = [self.containsEntities setByAddingObject: [NSEntityDescription insertNewObjectForEntityForName: @"Entity2" 
													   inManagedObjectContext: managedObjectContext]];