不使用计时器的If语句

Question

当10秒击中计时器时。我想要改变背景颜色。现在我的代码不起作用。当代码到达10秒时，没有任何更改。我也认为计时器不起作用。

@IBOutlet var espn: UILabel!

var TIMER = Timer()
var seconds = 0


override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)




    if seconds == 10{self.view.backgroundColor = UIColor.red
    }

}
@IBAction func startTimer() {       

        TIMER = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(threeVC.clocker), userInfo: nil, repeats: true)


}


@objc func clocker() {
    seconds += 1
    espn.text = String( seconds)   
    }
}

Answer 1

试试下面的代码：

@IBOutlet var espn: UILabel!

var TIMER = Timer()
var seconds = 0


override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)        
}

@IBAction func startTimer() {

    TIMER = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(threeVC.clocker), userInfo: nil, repeats: true)


}


@objc func clocker() {
    seconds += 1
    espn.text = String( seconds)
    if seconds == 10{
        self.view.backgroundColor = UIColor.red
        print("soda")
    }
}

如果语句应该用@objc func clocker()而不是viewDidAppear编写