Swift 5 - 计时器未触发

Question

我有以下内容，

class someViewController : ViewController{
    var timer:Timer? = nil

    override func viewDidLoad() {
        timer = Timer.scheduledTimer(timeInterval: 5.0, target: self, selector: #selector(fire), userInfo: nil, repeats: true)

}

@objc func fire(){
print("fired")
}
    
}

点火功能从未被触发，我不明白为什么，我错过了什么？

Answer 1

问题是：计时器需要在主线程上调度：

DispatchQueue.main.async {  
let timer = Timer.scheduledTimer(timeInterval: self.BLINK_TIMEOUT, target: self, selector: #selector(self.clearTimer), userInfo: nil, repeats: false)

}