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ios - 在导航栏中使用提示时自动布局警告

问题描述

我正在使用带有提示的导航栏，如下所示： 在此处输入图像描述

我在控制台中收到以下自动布局警告：

2019-09-01 21:26:03.225576+0200 Hortus[85622:2386450] [LayoutConstraints] Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want. 
Try this: 
    (1) look at each constraint and try to figure out which you don't expect; 
    (2) find the code that added the unwanted constraint or constraints and fix it. 
(
    "<NSLayoutConstraint:0x600002d16990 UILabel:0x7fc9eb816f50'Testen'.centerX == _UINavigationBarModernPromptView:0x7fc9ebe27780.centerX   (active)>",
    "<NSLayoutConstraint:0x600002d15c20 UILabel:0x7fc9eb816f50'Testen'.leading >= UILayoutGuide:0x6000037571e0'UIViewLayoutMarginsGuide'.leading   (active)>",
    "<NSLayoutConstraint:0x600002d10ff0 '_UITemporaryLayoutWidth' _UINavigationBarModernPromptView:0x7fc9ebe27780.width == 0   (active)>",
    "<NSLayoutConstraint:0x600002d16a30 'UIView-leftMargin-guide-constraint' H:|-(8)-[UILayoutGuide:0x6000037571e0'UIViewLayoutMarginsGuide'](LTR)   (active, names: '|':_UINavigationBarModernPromptView:0x7fc9ebe27780 )>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x600002d15c20 UILabel:0x7fc9eb816f50'Testen'.leading >= UILayoutGuide:0x6000037571e0'UIViewLayoutMarginsGuide'.leading   (active)>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKitCore/UIView.h> may also be helpful.

2019-09-01 21:26:03.226198+0200 Hortus[85622:2386450] [LayoutConstraints]     Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want. 
Try this: 
    (1) look at each constraint and try to figure out which you don't expect; 
    (2) find the code that added the unwanted constraint or constraints and fix it. 
(
    "<NSLayoutConstraint:0x600002d16990 UILabel:0x7fc9eb816f50'Testen'.centerX == _UINavigationBarModernPromptView:0x7fc9ebe27780.centerX   (active)>",
    "<NSLayoutConstraint:0x600002d15540 UILabel:0x7fc9eb816f50'Testen'.trailing <= UILayoutGuide:0x6000037571e0'UIViewLayoutMarginsGuide'.trailing   (active)>",
    "<NSLayoutConstraint:0x600002d10ff0 '_UITemporaryLayoutWidth' _UINavigationBarModernPromptView:0x7fc9ebe27780.width == 0   (active)>",
    "<NSLayoutConstraint:0x600002d14320 'UIView-rightMargin-guide-constraint' H:[UILayoutGuide:0x6000037571e0'UIViewLayoutMarginsGuide']-(8)-|(LTR)   (active, names: '|':_UINavigationBarModernPromptView:0x7fc9ebe27780 )>"

    "<NSAutoresizingMaskLayoutConstraint:0x60000043be30 h=--& v=--& _UINavigationBarModernPromptView:0x7fb3c6416640.width == 0   (active)>",
    "<NSLayoutConstraint:0x600000421400 UILabel:0x7fb3c66d8bf0'Plant guide'.centerX == _UINavigationBarModernPromptView:0x7fb3c6416640.centerX   (active)>",
    "<NSLayoutConstraint:0x600000421f90 UILabel:0x7fb3c66d8bf0'Plant guide'.trailing <= UILayoutGuide:0x600001e58fc0'UIViewLayoutMarginsGuide'.trailing   (active)>",
    "<NSLayoutConstraint:0x600000421e00 'UIView-rightMargin-guide-constraint' H:[UILayoutGuide:0x600001e58fc0'UIViewLayoutMarginsGuide']-(20)-|(LTR)   (active, names: '|':_UINavigationBarModernPromptView:0x7fb3c6416640 )>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x600002d15540 UILabel:0x7fc9eb816f50'Testen'.trailing <= UILayoutGuide:0x6000037571e0'UIViewLayoutMarginsGuide'.trailing   (active)>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKitCore/UIView.h> may also be helpful.

这些警告是针对导航栏中的提示给出的，但我没有为导航栏设置自动布局约束。这应该由IOS自己处理。

我能做些什么来修复这些警告？

[编辑] 连接到视图控制器时，prepare() 中会给出警告。我在prepare() 中设置了提示。segue 是一个故事板参考，并被定义为“模态呈现”。故事板参考引用了 UINavigationController。提示设置在导航控制器的根视图控制器上。

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

    if let identifier = segue.identifier {
        switch identifier {

        case "editImage":
            let nc = segue.destination as? TTImageNavigationController
            if let rvc = nc?.rootViewController as? TTImageEditorController {
                rvc.navigationItem.prompt = navigationItem.prompt
            }

        default:
            break
        }
    }
}

[编辑] 似乎大多数做出反应的人都不清楚这个问题。再次......我没有在代码或情节提要中设置任何自动布局设置。在 segue 之前的 prepare() 函数中设置提示后，导航栏出现问题。上面给出了代码。任何说我必须更改或检查我的约束的反应都没有帮助，因为没有要检查的约束！

[编辑] 按照 Mohsen 的要求，我在 github 上创建了一个小示例项目：https ://bitbucket.org/Leontien/navigationbarautolayoutwarning/src/master/

标签： iosswiftautolayoutuinavigationbar

解决方案

这不是你的错误。这是苹果的错误。忽略控制台。向 Apple 提交报告并继续前进。

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