参考链接： http://blog.csdn.net/Hello_Hwc/article/details/51859330
官方地址：https://github.com/ReactiveX/RxSwift
demo解读：
一、number

        Observable.combineLatest(number1.rx.text, number2.rx.text, number3.rx.text) { textValue1, textValue2, textValue3 -> Int in
                return (Int(textValue1) ?? 0) + (Int(textValue2) ?? 0) + (Int(textValue3) ?? 0)
            }
            .map { $0.description }
            .bindTo(result.rx.text)
            .addDisposableTo(disposeBag)

名词释义：
1.Observable
2.combineLatest
3.??
4.map
5.bingTo
6.addDisposableTo
7.disposeBag
二、valiadation

       let myUserNameValid = usernameOutlet.rx.text
           .map{$0.characters.count > 6}
           .shareReplay(1)
       
       let myPasswordValid = passwordOutlet.rx.text
           .map{$0.characters.count > 6}
           .shareReplay(1)
       
       let myEverythingValid = Observable.combineLatest(usernameValid, passwordValid) {$0 && $1}
           .shareReplay(1)
       
       myUserNameValid
           .bindTo(usernameValidOutlet.rx.hidden)
           .addDisposableTo(disposeBag)
       
       myPasswordValid
           .bindTo(passwordValidOutlet.rx.hidden)
           .addDisposableTo(disposeBag)
       
       myEverythingValid
           .bindTo(doSomethingOutlet.rx.enabled)
           .addDisposableTo(disposeBag)
       
       doSomethingOutlet.rx.tap
           .subscribe(onNext: {[weak self] in self?.showAlert()})
           .addDisposableTo(disposeBag)

名词释义：
1.shareReplay(1)
2.subScribe(onNext:{[weak seld] in self?.showAlert() })
三、Geolocation Subscription

private extension Reactive where Base: UILabel {
    var driveCoordinates: AnyObserver<CLLocationCoordinate2D> {
        return UIBindingObserver(UIElement: base) { label, location in
            label.text = "Lat: \(location.latitude)\nLon: \(location.longitude)"
        }.asObserver()
    }
}

private extension Reactive where Base: UIView {
    var driveAuthorization: AnyObserver<Bool> {
        return UIBindingObserver(UIElement: base) { view, authorized in
            if authorized {
                view.isHidden = true
                view.superview?.sendSubview(toBack:view)
            }
            else {
                view.isHidden = false
                view.superview?.bringSubview(toFront:view)
            }
        }.asObserver()
    }
}

        let geolocationService = GeolocationService.instance

        geolocationService.authorized
            .drive(noGeolocationView.rx.driveAuthorization)
            .addDisposableTo(disposeBag)
        
        geolocationService.location
            .drive(label.rx.driveCoordinates)
            .addDisposableTo(disposeBag)

        button.rx.tap
            .bindNext { [weak self] in
                self?.openAppPreferences()
            }
            .addDisposableTo(disposeBag)
        
        button2.rx.tap
            .bindNext { [weak self] in
                self?.openAppPreferences()
            }
            .addDisposableTo(disposeBag)
    }
    
    private func openAppPreferences() {
        UIApplication.shared.openURL(URL(string: UIApplicationOpenSettingsURLString)!)
    }

名词释义：
1.drive
2.asObserver