Blocks instead of performSelector:withObject:afterDelay: [duplicate]

There’s no built-in way to do that, but it’s not too bad to add via a category:

@implementation NSObject (PerformBlockAfterDelay)

- (void)performBlock:(void (^)(void))block 
          afterDelay:(NSTimeInterval)delay 
{
    block = [[block copy] autorelease];
    [self performSelector:@selector(fireBlockAfterDelay:) 
               withObject:block 
               afterDelay:delay];
}

- (void)fireBlockAfterDelay:(void (^)(void))block {
    block();
}

@end

Credit to Mike Ash for the basic implementation.