解雇UIViewController

Question

我在另一个上展示了一个UIViewController。当我关闭呈现的UIViewController并返回到当前的UIViewController并尝试更新UILabel文本时，它不会更新。我不知道为什么下面的customTimeViewController是我介绍的UIViewController。当单击一个按钮时，我的下面的函数被委托调用。我尝试更新我的UILabel（targetTimeText）文本，但未更新。

我尝试了layoutIfNeeded()，setNeedsLayout()和setNeedsDisplay()。没有任何帮助。

func selectedCustomTime(minutes: Int, seconds: Int) {
    customTimeViewController?.dismiss(animated: true, completion: nil)
    self.targetTimeText.text = GameTimeUtility.convertTimeToHumanReadable(time: minutes*60+seconds)
}

Answer 1

在这种情况下，您可以使用通知协议或代理协议。尝试使用协议的此代码，并将变量或函数名称更改为当前代码。

protocol MydataDelegate{
    func passingData(mystring: String)
}

Class SecondViewController: UIViewController{

    var mdataDelegate: MydataDelegate!

    func selectedCustomTime(minutes: Int, seconds: Int) {
        mdataDelegate.passingData(mystring: GameTimeUtility.convertTimeToHumanReadable(time: minutes*60+seconds))
        customTimeViewController?.dismiss(animated: true, completion: nil)
    }

}

Class FirstViewController: UIViewController,MydataDelegate{

    func openSecondVC(){

        // Mark: Try your code that open new viewcontroller but don't forget pass your delegate
        let mainStoryboard = UIStoryboard(name: "Storyboard", bundle: NSBundle.mainBundle())
        let vc = mainStoryboard.instantiateViewControllerWithIdentifier("SecondViewController") as! SecondViewController
        vc.mdataDelegate = self
        self.presentViewController(vc, animated: true, completion: nil)
    }

    func passingData(mystring: String){
        self.targetTimeText.text = mystring
    }

}

Answer 2

我解决了，

我通过调用addSubview（）方法在代码中添加了UILabel（targetTimeText），如果我调用setNeedsLayout（）添加了它，那么一切正常。请在下面检查

self.view.addSubview(targetTimeText)
view.setNeedsLayout()