var timeObserve: DispatchSourceTimer! //定时任务
//MARK: GCD定时器倒计时
///
/// - Parameters:
/// - timeInterval: 间隔时间
/// - repeatCount: 重复次数
/// - handler: 循环事件,闭包参数: 1.timer 2.剩余执行次数
func dispatchTimer(timeInterval: Double, repeatCount: Int, handler: @escaping (DispatchSourceTimer?, Int) -> Void) {
if repeatCount <= 0 {
return
}
if timeObserve != nil {
timeObserve.cancel()//销毁旧的
}
// 初始化DispatchSourceTimer前先销毁旧的，否则会存在多个倒计时
let timer = DispatchSource.makeTimerSource(flags: [], queue: DispatchQueue.main)
timeObserve = timer
var count = repeatCount
timer.schedule(deadline: .now(), repeating: timeInterval)
timer.setEventHandler {
count -= 1
DispatchQueue.main.async {
handler(timer, count)
}
if count == 0 {
timer.cancel()
}
}
timer.resume()
}
