Enabling UIButton using RxSwift and RxCocoa

validationCheckWithRxCocoaAndRxSwift.swift

let nameFieldIsValidObservable = nameInputField.rx_text.map {
    $0.characters.count > 0
}

let otherNameFieldIsValidObservable = otherNameInputField.rx_text.map {
    $0.characters.count > 0
}

let m = Observable.combineLatest(nameFieldIsValidObservable, otherNameFieldIsValidObservable) { (nameIsValid, otherNameIsValid) in
    return nameIsValid && otherNameIsValid
}

m.bindTo(createButton.rx_enabled).addDisposableTo(disposeBag) // disposeBag is a property like `let disposeBag = DisposeBag()`