在CNContactViewController弹出之前显示了意外的图标

Question

我正在尝试使用Swift创建一个CNContactView forNewContact。单击按钮后，应弹出CNContactViewController，但是在弹出视图之前会出现一些奇怪的徽标。如何解决这个问题？

我正在使用Swift 4.1，但是我的旧项目Swift 3.3中存在相同的问题。 Xcode版本是9.4.1。

这是视频演示：Video demo for Bug

这是项目：project

import UIKit
import Contacts
import ContactsUI

class ViewController: UIViewController,CNContactViewControllerDelegate {
    override func viewDidLoad() {
        super.viewDidLoad()
    }
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
    func contactViewController(_ vc: CNContactViewController,     didCompleteWith con: CNContact?) {
        vc.dismiss(animated: true)
    }
    @IBAction func addContact(_ sender: Any) {
        let con = CNMutableContact()
        con.givenName = "test"
        let unkvc = CNContactViewController(forNewContact: con)
        unkvc.delegate = self as CNContactViewControllerDelegate
        self.present(UINavigationController(rootViewController: unkvc),     animated:true)
        self.view.endEditing(true)
    }
}

2018-06-19 15:52:13.911766-0700 contactbook[5319:1973728] Access to     PassKit Shared Cache file denied. Please verify sandbox exceptions and/or     file a Radar.
2018-06-19 15:52:14.087053-0700 contactbook[5319:1973728] [App] if we're in the real pre-commit handler we can't actually add any new fences due to CA restriction
2018-06-19 15:52:14.269548-0700 contactbook[5319:1973728] [MC] System group container for systemgroup.com.apple.configurationprofiles path is /private/var/containers/Shared/SystemGroup/systemgroup.com.apple.configurationprofiles
2018-06-19 15:52:14.270754-0700 contactbook[5319:1973728] [MC] Reading from public effective user settings.
2018-06-19 15:52:14.342483-0700 contactbook[5319:1973728] [Snapshotting] Snapshotting a view (0x10334a5a0, _UIButtonBarStackView) that has not been rendered at least once requires afterScreenUpdates:YES.
2018-06-19 15:52:14.342971-0700 contactbook[5319:1973728] [Snapshotting] Snapshotting a view (0x10334ab00, _UIButtonBarStackView) that has not been rendered at least once requires afterScreenUpdates:YES.

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