Question

我有这个简单的应用程序我试图写，用户应该可以使用谷歌搜索找到图像，问题是当他用长按选择照片时，我是收到错误：警告：尝试显示其视图不在窗口层次结构中！

如果我在ViewController中用self.navigationController!.presentViewController(nav, animated: true, completion: nil)替换self.navigationController!.pushViewController(nav, animated: true)，一切正常。这让我疯狂。

的AppDelegate：

    let viewController = ViewController()
    let navController = UINavigationController.init(rootViewController: viewController)

    let frame = UIScreen.mainScreen().bounds
    window = UIWindow.init(frame: frame)
    window?.rootViewController = navController
    window?.makeKeyAndVisible()

    // Override point for customization after application launch.
    return true

的ViewController：

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    let search = UIBarButtonItem.init(barButtonSystemItem: .Search, target: self, action: Selector("searchImages"))
    self.setToolbarItems([search], animated: false)
    self.navigationController?.setToolbarHidden(false, animated: false)
}

func searchImages() {
    let searchVC = SearchImageViewController()
    let nav = UINavigationController.init(rootViewController: searchVC)
    self.navigationController!.presentViewController(nav, animated: true, completion: nil)
}

最后是SearchImageViewController：

weak var webView: UIWebView?

override func loadView() {
    let webView = UIWebView.init(frame: CGRectZero)
    self.view = webView
    self.webView = webView
}

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.
    let done = UIBarButtonItem.init(barButtonSystemItem: .Done, target: self, action: Selector("done"))
    self.navigationItem.rightBarButtonItem = done

    let url = NSURL.init(string: "http://images.google.com/ncr")
    let request = NSURLRequest.init(URL: url!)
    webView!.loadRequest(request)
}

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

func done() {


}

任何想法都将不胜感激。顺便说一下，显示正常的AlertController工作正常（在done函数内）。

Swift：当呈现视图控制器而未按下时，UIWebView（和WKWebView）无法呈现AlertController

0 个答案: