How to use NSWindowDidExposeNotification

Question

Hi,

I am trying to update another windows when the one becomes visible. So I found the NSWindowDidExposeNotification and tried to work with it, so I wrote in my awakeFromNib:

// MyClass.m
- (void)awakeFromNib {
    NSNotificationCenter *nc = [NSNotificationCenter defaultCenter];
    [nc addObserver:self
           selector:@selector(mentionsWindowDidExpose:)
               name:NSWindowDidExposeNotification
             object:nil];
}

and implemented the method

// MyClass.h
- (void)mentionsWindowDidExpose:(id)sender;

// MyClass.m
- (void)mentionsWindowDidExpose:(id)sender {
    NSLog(@"test");
}

But it never gets called which is odd. What do I do wrong here?