Using KVO with NSSingleton

KVO + Singleton Example

Bank *b = [Bank instance];
Person *p = [Person instance];
[b addObserver:p forKeyPath:@"accountBalance" options:NSKeyValueObservingOptionNew context:NULL];
b.accountBalance = [NSNumber numberWithInt:99];


#import "NSSingleton.h"
@interface Bank : NSSingleton
@property (nonatomic, strong) NSNumber *accountBalance;
@end

#import "Bank.h"
@implementation Bank
@synthesize accountBalance;
@end

#import "NSSingleton.h"
@interface Person : NSSingleton
@end

#import "Person.h"
@implementation Person
-(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{
    NSLog(@"keypath: %@", keyPath);
    NSLog(@"object: %@", [object description]);
}
@end