NSCoder - archive pointer?

Question

I have an objective-c class that contains a pointer to another class. I want to archive an instance of this class through NSCoder:

@interface Barn
{
    int m_numHorses;

    // Barn does not allocate this instance, it just points to it.
    Farmer* m_pFarmer;
}
@end

...

- (void)encodeWithCoder:(NSCoder *)encoder
{
    [encoder encodeInt:m_numHorses forKey:@"numHorses"];
    [encoder encode?:m_pFarmer forKey:@"pFarmer"];
}

- (void) setPointer:(Farmer*)pFarmer
{
    m_pFarmer = pFarmer;
}

How can I archive the m_pFarmer pointer? This does not make any sense to me, since all this is an address, and I do not see that NSCoder can serialize to disk for you so that it knows how to restore the link later when deserializing?

Answer 1

You cannot directly encode the pointer, because when you unload objects, the value of the pointer will be completely different. I mean, you can save it using

encodeValueOfObjCType:@encode(id) at:&m_pFarmer 

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Answer 2

encodeObject: NSCoding Farmer, .

Answer 3

, BJ.

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Answer 4

, ( , Farmer , ), NSInteger.

. [encoder encodeInteger:(NSInteger)m_pFarmer forKey:@"pFarmer"];

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Answer 5

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var uniqueIdentifier: String = NSUUID().UUIDString

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, CoreData, ...

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