I'd like to use KVO to observe changes to a value in an NSMutableDictionary. However, I'm finding that it's not working because the key in the dictionary that I'd like to observe contains dots.
What is the correct way to add an observer for a key path that contains dots?
For example, the solution to this question works fine:
@interface Foo : NSObject @end
@implementation Foo
- (void) observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
NSLog(@"observing: -[%@ %@]", object, keyPath);
NSLog(@"change: %@", change);
}
@end
int main (int argc, const char * argv[]) {
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
Foo * f = [[Foo alloc] init];
NSMutableDictionary * d = [NSMutableDictionary dictionary];
[d addObserver:f forKeyPath:@"foo" options:0 context:NULL];
[d setObject:@"bar" forKey:@"foo"];
[d removeObjectForKey:@"foo"];
[d removeObserver:f forKeyPath:@"foo"];
[f release];
[pool drain];
return 0;
}
However, this does not work:
@interface Foo : NSObject @end
@implementation Foo
- (void) observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
NSLog(@"observing: -[%@ %@]", object, keyPath);
NSLog(@"change: %@", change);
}
@end
int main (int argc, const char * argv[]) {
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
Foo * f = [[Foo alloc] init];
NSMutableDictionary * d = [NSMutableDictionary dictionary];
[d addObserver:f forKeyPath:@"com.company.foo" options:0 context:NULL];
[d setObject:@"bar" forKey:@"com.company.foo"];
[d removeObjectForKey:@"com.company.foo"];
[d removeObserver:f forKeyPath:@"com.company.foo"];
[f release];
[pool drain];
return 0;
}
