Question

我有一个活动指示器，我在长时间运行的过程之前显示。在此过程之后，我只是尝试再次删除该指标。

我无法做到。指示器显示但随后在我的屏幕上永远停留，即使我在主线程中将其删除。

有人可以帮助我吗？

代码：

// Activity Indicator Variables
var messageFrame = UIView()
var activityIndicator = UIActivityIndicatorView()
var strLabel = UILabel()

// in viewdidappear
showprogressIndicator("Please Wait", true)
dispatch_async(dispatch_get_main_queue()) {
    sleep(2); // LONG RUNNING TASK
    dispatch_async(dispatch_get_main_queue()) {

        for subview in self.messageFrame.subviews {
            subview.removeFromSuperview();

        }

        self.messageFrame.removeFromSuperview()
        //self.saveButton.enabled = true
    }
}



func showprogressIndicator(msg:String, _ indicator:Bool ) {
    var strLabel = UILabel(frame: CGRect(x: 50, y: 0, width: 200, height: 50))
    strLabel.text = msg
    strLabel.textColor = UIColor.whiteColor()
    var messageFrame = UIView(frame: CGRect(x: view.frame.midX - 90, y: view.frame.midY - 25 , width: 180, height: 50))
    messageFrame.layer.cornerRadius = 15
    messageFrame.backgroundColor = UIColor(white: 0, alpha: 0.7)
    if indicator {
        activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: UIActivityIndicatorViewStyle.White)
        activityIndicator.frame = CGRect(x: 0, y: 0, width: 50, height: 50)
        activityIndicator.startAnimating()
        messageFrame.addSubview(activityIndicator)
    }
    messageFrame.addSubview(strLabel)
    view.addSubview(messageFrame)
    //self.messageFrame.removeFromSuperview()
}

Answer 1

您的代码中有多处错误。 Sleep（）不是延迟执行某一部分的函数。请查看修订版本并将其作为参考。


    var messageFrame: UIView!

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

        showprogressIndicator("Please Wait", true)
        dispatch_after(dispatch_time(
            DISPATCH_TIME_NOW,
            Int64(2 * Double(NSEC_PER_SEC))
            ), dispatch_get_main_queue(), { () -> Void in
                for subview in self.messageFrame.subviews {
                    subview.removeFromSuperview();
                }
                self.messageFrame.removeFromSuperview()
        })
    }

    func showprogressIndicator(msg:String, _ indicator:Bool ) {
        let strLabel = UILabel(frame: CGRect(x: 50, y: 0, width: 200, height: 50))
        strLabel.text = msg
        strLabel.textColor = UIColor.whiteColor()
        messageFrame = UIView(frame: CGRect(x: view.frame.midX - 90, y: view.frame.midY - 25 , width: 180, height: 50))
        messageFrame.layer.cornerRadius = 15
        messageFrame.backgroundColor = UIColor(white: 0, alpha: 0.7)
        if indicator {
            let activityIndicator = UIActivityIndicatorView(activityIndicatorStyle: UIActivityIndicatorViewStyle.White)
            activityIndicator.frame = CGRect(x: 0, y: 0, width: 50, height: 50)
            activityIndicator.startAnimating()
            messageFrame.addSubview(activityIndicator)
        }
        messageFrame.addSubview(strLabel)
        view.addSubview(messageFrame)
    }

Answer 2

您的代码问题是您在显示进度指示器的同时向var messageFrame添加了另一个对象（self.view），但是当轮到它将其删除时，您将删除一个完全不同的对象（self.messageFrame）。
要解决此问题，请从showprogressIndicator方法中删除本地声明，然后直接将分配的对象分配给self.messageFrame。

self.messageFrame = UIView(frame: CGRect(x: view.frame.midX - 90, y: view.frame.midY - 25 , width: 180, height: 50))

如何从父母视图中删除uiview？

2 个答案: