Button倒计时
func showCountdownTime(_ time: Int, button: UIButton?) {
var time = time
let codeTimer = DispatchSource.makeTimerSource(flags: .init(rawValue: 0),
queue: DispatchQueue.global())
codeTimer.schedule(deadline: .now(), repeating: .milliseconds(1000)) //此处方法与Swift 3.0 不同
codeTimer.setEventHandler {
time = time - 1
DispatchQueue.main.async {
button?.isEnabled = false
}
if time < 0 {
codeTimer.cancel()
DispatchQueue.main.async {
button?.isEnabled = true
button?.setTitle("发送验证码", for: .normal)
}
return
}
DispatchQueue.main.async {
button?.setTitle("\(time)秒", for: .normal)
}
}
codeTimer.activate()
}
