Animation Delay Signal

spike.m

RACSignal *isWorkingSignal = [[RACObserve(object, isWorking)
        map:^id(NSNumber *isWorking) {
            if (YES == [isWorking boolValue]) {
                NSTimeInterval delayInterval = 2; // seconds
                return [[RACSignal return:isWorking] delay:delayInterval];
            } else {
                return [RACSignal return:isWorking];
            }
        }] switchToLatest];

[isWorkingSignal subscribeNext:^(NSNumber *isWorking) {
    if (YES == [isWorking boolValue]) {
        [activityIndicator startAnimating];
    }
    else {
        [activityIndicator stopAnimating];
    }
}];