objective c - iOS - Core Data - Saving an object that contains an array of Objects -

i'm getting started core data, (and i'm trying use magical record). i'm creating pretty simple payment tracking app.

i save payment object has array of debtors. payment object looks like

@class debtor;  @interface payment : nsobject @property (strong, nonatomic) nsstring *paymentamountstring; @property (strong, nonatomic) nsstring *titlestring; @property (strong, nonatomic) nsarray *debtorsarray; @property (strong, nonatomic) nsdate *duedate; @property (strong, nonatomic) nsstring *notesstring; @end 

and debtorsarray array of debtor objects

@interface debtor : nsobject @property (strong, nonatomic) nsstring *namestring; @property (strong, nonatomic) nsstring *amountowedstring; 

how should go saving object since contains array. need create 2 different entities, relationship between payment , debtor? how do this, , how ensure fetched properly?

create 1 entity payment. have use 'transformable' data type attribute debtorsarray within entity.

then implement following methods in debtor class:

- (void)encodewithcoder:(nscoder *)acoder{     [acoder encodeobject:self.namestring forkey:@"namestring"];     [acoder encodeobject:self.amountownedstring forkey:@"amountownedstring"]; }  -(id)initwithcoder:(nscoder *)adecoder{     if(self = [super init]){         self.namestring = [adecoder decodeobjectforkey:@"namestring"];         self.amountownedstring = [adecoder decodeobjectforkey:@"amountownedstring"];     }     return self; } 

entity should fetched other fetch query.

hope helps.