快速不平衡调用开始/结束外观转换

这已经困扰我一段时间了。我有一个UISplitViewController里面一个UITabBarController。主视图是一个TableView。当我单击一个单元格时，我会弹出一个非常基本的视图控制器，其中只有一个UIButton居中。这是视图控制器的代码：

class TestViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    @IBOutlet weak var button: UIButton!

    override func viewDidLoad() {
        super.viewDidLoad()
    }

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

    @IBAction func buttonPressed(sender: AnyObject) {
        let pickerC = UIImagePickerController()
        pickerC.delegate = self

        pickerC.modalPresentationStyle = .Popover
        pickerC.popoverPresentationController?.sourceView = button as UIView
        pickerC.popoverPresentationController?.sourceRect = (button as UIView).bounds
        pickerC.popoverPresentationController?.permittedArrowDirections = UIPopoverArrowDirection.Any
        self.presentViewController(pickerC, animated: true, completion: nil)//4
    }

    func imagePickerController(picker: UIImagePickerController, didFinishPickingImage image: UIImage!, editingInfo: [NSObject : AnyObject]!) {
        self.dismissViewControllerAnimated(true, completion: nil)
    }

    func imagePickerControllerDidCancel(picker: UIImagePickerController) {
       self.dismissViewControllerAnimated(true, completion: nil)
    }
}

如果我单击取消或选择和图像，选择器控制器将正确关闭。当我单击后退按钮返回 TableView 时，问题出现了，我收到：

Unbalanced calls to begin/end appearance transitions for <TestViewController: 0x7fb882a72380>.

The TestViewController这是非常基本的，那么为什么会发生这种情况呢？

如果您在上一个事务（动画）正在进行时尝试推送新的视图控制器，则会出现此问题。因此，请检查您的代码流程并进行适当的更改。检查您的关闭和呈现视图动画。您可以使用属性 setAnimation 来“是/否”解决此问题

设置动画：否，可能可以解决您的问题