rxswift_practice_001.swift

// 模擬 indicator 顯示/隱藏狀態
let indicator = Variable(false)

// 按鈕
lazy var loginButton: UIButton = {
    let button = UIButton(type: .system)
    button.tintColor = UIColor.red
    button.setTitle("登入", for: .normal)
    return button
}()

//...

// 依據是否正在讀取中來改變按鈕狀態
self.indicator.asObservable().map{ !$0 }.bind(to: loginButton.rx.isEnabled).disposed(by: disposeBag)

// 按鈕點按 Observer
let t = self.loginButton.rx.tap
// Xcode 中跟上面連著寫會沒有提示...所以這邊特別用 t 來放 tap
t.flatMap { [weak self] () -> Observable<Void> in
    print(1)
    self?.indicator.value = true
    // 5 秒後繼續
    return Observable<Void>.just().delay(5, scheduler: MainScheduler.instance)
}.subscribe(onNext: {[weak self] () in
    print(2)
    self?.indicator.value = false
}).disposed(by: disposeBag)