ios - 让约束在大小类中工作

Question

因此，我正在研究 Xcode 6 beta 中的大小类。我对图像设置了一些约束，使其根据对应于 iPhone 纵向和横向的尺寸类别处于不同的位置。

约束在下图中可见。如您所见，当我处于 Compact/Compact 时，一些约束被“安装”，而另一些则没有，而在 Compact/Regular 中，其他约束被安装。

但是，我得到一个错误(在两个屏幕截图中都略微可见)基本上声称我卸载的约束干扰了我安装的约束(如果它们同时运行，则为真)但卸载的约束不应该对于每个大小级别甚至不运行？所有已安装的约束都不会导致彼此出现问题。

出现的错误是:

2014-06-30 21:14:26.215 TV Tracker[26417:1434692] SetAppThreadPriority: setpriority failed with error 45
2014-06-30 21:14:26.372 TV Tracker[26417:1434692] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
"<NSLayoutConstraint:0x10bb11da0 H:|-(24)-[UILabel:0x10bb4db70'TV Tracker uses your Trak...']   (Names: '|':UIControl:0x10bb2db60 )>",
"<NSLayoutConstraint:0x10bb11df0 H:[UIImageView:0x10bb44740]-(>=18)-[UILabel:0x10bb4db70'TV Tracker uses your Trak...']>",
"<NSLayoutConstraint:0x10bb2f420 H:|-(20)-[UIButton:0x10bb35470'Sign In']   (Names: '|':UIControl:0x10bb2db60 )>",
"<NSLayoutConstraint:0x10bb2f470 UIButton:0x10bb35470'Sign In'.leading == UIImageView:0x10bb44740.leading>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x10bb11df0 H:[UIImageView:0x10bb44740]-(>=18)-[UILabel:0x10bb4db70'TV Tracker uses your Trak...']>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2014-06-30 21:14:26.373 TV Tracker[26417:1434692] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
"<NSLayoutConstraint:0x10bb11e90 H:[UILabel:0x10bb4db70'TV Tracker uses your Trak...']-(23)-|   (Names: '|':UIControl:0x10bb2db60 )>",
"<NSLayoutConstraint:0x10bb11ee0 UILabel:0x10bb4db70'TV Tracker uses your Trak...'.trailing == UIButton:0x10bb44ec0'Register'.trailing>",
"<NSLayoutConstraint:0x10bb2f510 H:[UIButton:0x10bb44ec0'Register']-(20)-|   (Names: '|':UIControl:0x10bb2db60 )>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x10bb11ee0 UILabel:0x10bb4db70'TV Tracker uses your Trak...'.trailing == UIButton:0x10bb44ec0'Register'.trailing>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2014-06-30 21:14:26.388 TV Tracker[26417:1434692] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
"<NSAutoresizingMaskLayoutConstraint:0x10bb49e10 h=-&- v=-&- UIControl:0x10bb2db60.width == UIViewControllerWrapperView:0x10d102000.width>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb55d10 h=-&- v=-&- UIViewControllerWrapperView:0x10d102000.width == UINavigationTransitionView:0x10bc6f770.width>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb3cda0 h=-&- v=-&- UINavigationTransitionView:0x10bc6f770.width == UILayoutContainerView:0x10bc6e3e0.width>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb29960 h=-&- v=-&- UILayoutContainerView:0x10bc6e3e0.width == UITransitionView:0x10bc73670.width>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb559e0 h=-&- v=-&- UITransitionView:0x10bc73670.width == UIWindow:0x10d068e70.width>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb56880 h=--- v=--- H:[UIWindow:0x10d068e70(320)]>",
"<NSLayoutConstraint:0x10bb2f420 H:|-(20)-[UIButton:0x10bb35470'Sign In']   (Names: '|':UIControl:0x10bb2db60 )>",
"<NSLayoutConstraint:0x10bb2f470 UIButton:0x10bb35470'Sign In'.leading == UIImageView:0x10bb44740.leading>",
"<NSLayoutConstraint:0x10bb44570 UIControl:0x10bb2db60.centerX == UIImageView:0x10bb44740.centerX>",
"<NSLayoutConstraint:0x10bb3c840 H:[UIImageView:0x10bb44740(92)]>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x10bb3c840 H:[UIImageView:0x10bb44740(92)]>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2014-06-30 21:14:26.389 TV Tracker[26417:1434692] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
"<_UILayoutSupportConstraint:0x10bd1c8a0 V:[_UILayoutGuide:0x10bb4acb0(64)]>",
"<_UILayoutSupportConstraint:0x10bd1fbf0 V:|-(0)-[_UILayoutGuide:0x10bb4acb0]   (Names: '|':UIControl:0x10bb2db60 )>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb56d40 h=-&- v=-&- UIControl:0x10bb2db60.height == UIViewControllerWrapperView:0x10d102000.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb56c60 h=-&- v=-&- UIViewControllerWrapperView:0x10d102000.height == UINavigationTransitionView:0x10bc6f770.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb3cbb0 h=-&- v=-&- UINavigationTransitionView:0x10bc6f770.height == UILayoutContainerView:0x10bc6e3e0.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb4a920 h=-&- v=-&- UILayoutContainerView:0x10bc6e3e0.height == UITransitionView:0x10bc73670.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb0e3a0 h=-&- v=-&- UITransitionView:0x10bc73670.height == UIWindow:0x10d068e70.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb44d20 h=--- v=--- V:[UIWindow:0x10d068e70(568)]>",
"<NSLayoutConstraint:0x10bb44520 UIControl:0x10bb2db60.centerY == UIImageView:0x10bb44740.centerY>",
"<NSLayoutConstraint:0x10bb445c0 V:[_UILayoutGuide:0x10bb4acb0]-(24)-[UIImageView:0x10bb44740]>",
"<NSLayoutConstraint:0x10bb49b60 V:[UIImageView:0x10bb44740(100)]>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x10bb49b60 V:[UIImageView:0x10bb44740(100)]>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
2014-06-30 21:14:26.396 TV Tracker[26417:1434692] 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. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
"<_UILayoutSupportConstraint:0x10bd13470 V:[_UILayoutGuide:0x10bb4c690(0)]>",
"<_UILayoutSupportConstraint:0x10bd13410 _UILayoutGuide:0x10bb4c690.bottom == UIControl:0x10bb2db60.bottom>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb56d40 h=-&- v=-&- UIControl:0x10bb2db60.height == UIViewControllerWrapperView:0x10d102000.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb56c60 h=-&- v=-&- UIViewControllerWrapperView:0x10d102000.height == UINavigationTransitionView:0x10bc6f770.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb3cbb0 h=-&- v=-&- UINavigationTransitionView:0x10bc6f770.height == UILayoutContainerView:0x10bc6e3e0.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb4a920 h=-&- v=-&- UILayoutContainerView:0x10bc6e3e0.height == UITransitionView:0x10bc73670.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb0e3a0 h=-&- v=-&- UITransitionView:0x10bc73670.height == UIWindow:0x10d068e70.height>",
"<NSAutoresizingMaskLayoutConstraint:0x10bb44d20 h=--- v=--- V:[UIWindow:0x10d068e70(568)]>",
"<NSLayoutConstraint:0x10bb11e40 UIControl:0x10bb2db60.centerY == UILabel:0x10bb4db70'TV Tracker uses your Trak...'.centerY + 0.25>",
"<NSLayoutConstraint:0x10bb2f3d0 V:[UILabel:0x10bb4db70'TV Tracker uses your Trak...']-(91)-[_UILayoutGuide:0x10bb4c690]>",
"<NSLayoutConstraint:0x10bb2d790 V:[UILabel:0x10bb4db70'TV Tracker uses your Trak...'(69)]>"
)

Will attempt to recover by breaking constraint 

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

我的 Compact/Compact 约束侧边栏看起来像

我的 Compact/Regular 约束侧边栏看起来像

此登录 Controller 的 View 层次结构:

Answer 1

我第一次尝试这个功能时遇到了同样的问题，直到我意识到“+”按钮告诉我的是什么。起初，我更改了大小类并删除了一个 View 并添加了一个 View ，或者删除了一个约束并添加了一个约束。那是错的!您不能在每个尺寸类别的基础上删除或添加 View 或约束；它们必须全部在每个尺寸等级中都存在——只有其中一些被标记为该尺寸等级的“已安装”，而其他则没有。

这里有一些进一步的建议。

• 查看屏幕截图的顶部。您从 Interface Builder 收到警告 - 并忽略它们。不要忽视他们!这些警告告诉您，您的约束并没有按照您的想法行事。

• 在 Canvas 左侧显示 View 层次结构列表(它隐藏在您的屏幕截图中)并继续查看和处理尺寸类的每个组合，直到不再有警告。它还会告诉您在质量案例中以及您正在查看的特定尺寸类别案例中存在哪些约束和 View (请参见下面的屏幕截图)。

• 使用右侧属性检查器中的“+”按钮确保您拥有每个相关尺寸类别案例的值。您不添加或删除约束或类别:您添加“已安装”按钮并标记它们的大小类别并选中或取消选中它们(再次参见屏幕截图)。

最后，使用预览助手确保 View 看起来像您期望的那样。请参阅下面的可爱动画。