計時器的創(chuàng)建

timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(time), userInfo: nil, repeats: true)

//開始計時器
timer.fire()
//暫停
timer.fireDate = Date.distantFuture
//繼續(xù)
timer.fireDate = NSDate.init() as Date
timer.fireDate = Date.distantPast
//消除計時器（頁面釋放是必須調(diào)用這個方法，不讓會讓頁面和定時器不會釋放）
timer.invalidate()
//滑動timer失效是添加
RunLoop.current.add(timer, forMode: .commonModes)