import UIKit

class ViewController: UIViewController {
var times = 5
var startBtn = UIButton()

override func viewDidLoad() {
    super.viewDidLoad()
    self.createButton()

// 三秒后执行
self.perform(#selector(sanmiaohou), with: nil, afterDelay: 3)
}
func sanmiaohou(){
print("三秒后执行")
}
var totalTimer:Timer?
func createButton() {
let button = UIButton(frame: CGRect(x: 20, y: 100, width: 100, height: 40))
self.view.addSubview(button)
button.backgroundColor = UIColor.red
button.addTarget(self, action: #selector(createTimer), for: .touchUpInside)
button.setTitle("开始", for: .normal)
self.startBtn = button

    let button2 = UIButton(frame: CGRect(x: 140, y: 100, width: 100, height: 40))
    self.view.addSubview(button2)
    button2.backgroundColor = UIColor.red
    button2.addTarget(self, action: #selector(endTimerAction), for: .touchUpInside)
    button2.setTitle("完全结束", for: .normal)
    
    let button3 = UIButton(frame: CGRect(x: 20, y: 250, width: 100, height: 40))
    self.view.addSubview(button3)
    button3.backgroundColor = UIColor.red
    button3.addTarget(self, action: #selector(createRoopTimer), for: .touchUpInside)
    button3.setTitle("子线程开启", for: .normal)
    
    let button21 = UIButton(frame: CGRect(x: 140, y: 200, width: 100, height: 40))
    self.view.addSubview(button21)
    button21.backgroundColor = UIColor.red
    button21.addTarget(self, action: #selector(continueTimerAction2), for: .touchUpInside)
    button21.setTitle("接着开始", for: .normal)

    let button213 = UIButton(frame: CGRect(x: 140, y: 320, width: 100, height: 40))
    self.view.addSubview(button213)
    button213.backgroundColor = UIColor.red
    button213.addTarget(self, action: #selector(stopTimerAction2), for: .touchUpInside)
    button213.setTitle("暂停", for: .normal)
}
//        方法名以scheduled开头的均不需要手动加入NSRunLoop
func createTimer() {
    /*参数：TimeInterval：触发时间，单位秒
     target：定时起触发对象
     selector：定时器响应方法
     userInfo：用户信息
     repeats：是否重复执行，YES 每个指定的时间重复执行，NO 只执行一次*/
    let timer:Timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(startTimerAction), userInfo: nil, repeats: true)
    self.totalTimer = timer
    self.totalTimer?.fire()
}
func startTimerAction() {
    print("timer start开始%ld",times)
    times = times - 1
    self.startBtn.setTitle("\(times)", for: .normal)
    if times == 0 {
        self.startBtn.setTitle("结束", for: .normal)
        print("定时器结束")
        self.totalTimer?.invalidate()
        times = 5
    }
}
func endTimerAction() {
    self.totalTimer?.invalidate()
    print("timer end完全结束")
}
//自动子线程定时器的创建
func createRoopTimer() {
        // 在子线程创建定时器
        /*scheduled 或 timer 方式创建*/
        let timer:Timer = Timer(timeInterval: 1.0,
                                    target: self,
                                    selector: #selector(self.updateTimer(timer:)),
                                    userInfo: nil,
                                    repeats: true)
        //这句话实现多线程，如果你的ScrollView是作为TableView的headerView的话，在拖动tableView的时候让轮播图仍然能轮播就需要用到这句话
        RunLoop.current.add(timer, forMode: RunLoopMode.commonModes)
        self.totalTimer = timer
}
var num:Int = 10
func updateTimer(timer:Timer) {
    num  = num + 1
    print("\(num)")
    // 满足条件后，停止当前的运行循环
    if (num == 15) {
        // 停止当前的运行循环
        /*一旦停止了运行循环，后续代码能够执行，执行完毕后，线程被自动销毁*/
        print("自线程停止", num)
        num = 10
    }
}
func stopTimerAction2(timer:Timer) {
    self.totalTimer?.fireDate = NSDate.distantFuture
    print("暂停timer end")
}
func continueTimerAction2() {
    self.totalTimer?.fireDate = NSDate.distantPast
    print("接着开始timer start")
}


override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

}