delegate proxying

proxy.m

#pragma mark - delegate proxying

- (BOOL)respondsToSelector:(SEL)selector {
    return (
            [super respondsToSelector:selector] ||
            [self.delegate respondsToSelector:selector]
            );
}

- (id)forwardingTargetForSelector:(SEL)selector {
    if ([super respondsToSelector:selector]) {
        return self;
    } else if ([self.delegate respondsToSelector:selector]) {
        return self.delegate;
    }
    return nil;
}

- (NSMethodSignature *)methodSignatureForSelector:(SEL)selector {
    if ([super respondsToSelector:selector]) {
        return [super methodSignatureForSelector:selector];
    } else if ([self.delegate respondsToSelector:selector]) {
        id delegate = self.delegate;
        return [delegate methodSignatureForSelector:selector];
    }
    return nil;
}

- (void)forwardInvocation:(NSInvocation *)invocation {
    // ignore
}