A useful pattern for UIKit's -setFoo:animated: methods

setFoo.m

- (void)setFoo:(BOOL)foo animated:(BOOL)animated {
    [super setFoo:foo animated:animated];

    dispatch_block_t changes = ^{
        if (foo) {
            someView.alpha = 1.0;
        }
        else {
            someView.alpha = 0.0;
        }
    };
    if (animated) {
        [UIView animateWithDuration:0.2 animations:changes];
    }
    else {
        changes();
    }
}