objc_setAssociatedObject function error in 64bit mode not in 32bit

Question

I am using a neat table view controller called SKSTableView in my project which allows each table row to have a number of sub rows. This code works perfectly in 32

Answer 1

I came across this as well but in a different scenario where I was needing to add a property to a tagged pointer type.

Here is what I came up with; it makes use of NSMapTable weakToStrongObjectsMapTable. It can even be used as a drop-in replacement for objc_setAssociatedObject/objc_getAssociatedObject for tagged pointers and regular object types:

static NSString* SomeVariableKey = @"SomeVariableKey";

@interface NSObject (SomeAddition)

- (void)setSomeVariable:(NSObject*)var {
    [[APObjectAssociationManager defaultManager] setValue:var forKey:SomeVariableKey forAssociatedObject:self];
}

- (NSObject*)someVariable {
    return [[APObjectAssociationManager defaultManager] valueForKey:SomeVariableKey forAssociatedObject:self];
}

@end


@interface APObjectAssociationManager ()

@property (nonatomic, strong) NSMapTable *associations;

@end

@implementation APObjectAssociationManager


- (id)init {
    self = [super init];

    if (self) {
        self.associations = [NSMapTable weakToStrongObjectsMapTable];
    }

    return self;
}

+ (APObjectAssociationManager*)defaultManager {
    static APObjectAssociationManager *instance = nil;

    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        instance = [[APObjectAssociationManager alloc] init];
    });

    return instance;
}

- (void)setValue:(id)value forKey:(NSString *)key forAssociatedObject:(NSObject*)associatedObject {


    NSMutableDictionary *dictionary = [self.associations objectForKey:associatedObject];

    if (!dictionary) {
        dictionary = [NSMutableDictionary dictionary];
        [self.associations setObject:dictionary forKey:associatedObject];
    }

    [dictionary setValue:value forKey:key];
}

- (id)valueForKey:(NSString *)key forAssociatedObject:(NSObject*)associatedObject {

    NSDictionary *dictionary = [self.associations objectForKey:associatedObject];
    return dictionary[key];
}

@end