Saving the enum property inside CoreData and its convenience

Question

One of my model objects has an enum property. To save it to CoreData, I used an NSNumber object.

However, I would like to access it as an enumeration type in a convenient way. What is the best practice to achieve this?

So far I have gone with the following code.

in MyObject.h

typedef enum _ABType {
    ABTypeUnknown,
    ABTypeValue1,
    ...
    ABTypeValueN
} ABType;

@interface MyObject : NSManagedObject

@property (nonatomic, retain) NSNumber * myPersistentEnum; // Defined in my Core Data model

@property (nonatomic) ABType myConvenientEnum;

in MyObject.m

@dynamic myPersistentEnum;

- (BOOL)isValidEnumValue {
    if (self.myPersistentEnum) {
        int intValue = [self.type intValue];
        if (intValue >= ABTypeValue1 && intValue <= ABTypeValueN) {
            return YES;
        }        
    }

    ELog(@"Undefined enumValue %@", self.myPersistentEnum);
    return NO;
}

- (ABType)myConvenientEnum {
    if ([self isValidEnumValue]) {
        return [self.type intValue];
    }

    return ABTypeUnknown;
}

- (void)setMyConvenientEnum:(ABType)enumValue {
    NSNumber *oldValue = [self.myPersistentEnum retain];
    self.myPersistentEnum = [NSNumber numberWithInt:enumValue];
    if ([self isValidEnumValue]) {
        [oldValue release];
    } else {
        self.myPersistentEnum = oldValue;
        [oldValue release];
    }
}

My questions:

• Is there something wrong in the code above?
• Is the intcorrect type used when converting an enumeration to NSNumber? (NSNumber does not provide a method -(enum)enumValue;)
• Could you leave the validation aspect to validate the CoreData model at runtime?
• [NEW] How can I make it clear to other developers that I need to use a convenient property, not the NSNumber property?

Answer 1

CoreData iOS 5 , NSNumber, .

FWIW, , , . enum - (int) myEnumValue - NSNumber, , - , .