swift - Swift 的 XCode 7 编译错误

Question

有人可以帮我解决这个问题吗？我添加了另一个 ViewController 并将其模态链接到原始 View Controller 。它最初有效，但我再次运行它，因为我对文本进行了更改，现在它无法编译。我删除了所有约束并删除了它说未正确链接的“按钮”。

2015-10-26 00:48:43.611 XXXX[5790:2031206] 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:0x15ce8dac0 V:|-(20)-[UIInputSetContainerView:0x15ce2e050]   (Names: '|':UITextEffectsWindow:0x15ce694a0 )>",
"<NSLayoutConstraint:0x15ce8e630 'UIInputWindowController-top' V:|-(0)-[UIInputSetContainerView:0x15ce2e050]   (Names: '|':UITextEffectsWindow:0x15ce694a0 )>")

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.
2015-10-26 00:48:44.446 XXXXX[5790:2031206] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<XXXXXX.CreateAnAccountViewController 0x15cd1fd40> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key SignUpLabel.'
*** First throw call stack:
(0x185198f5c 0x19a67ff80 0x185198c1c 0x18600f534 0x18aa4f9b8 0x18ab9b4b8 0x1850c2acc 0x18ab99ea0 0x18aa52cfc 0x18a827ea8 0x18a6ef258 0x18a6ef1b0 0x18af713a4 0x18aa3705c 0x18aa5c508 0x18aa5f294 0x18a7e60c0 0x18adea5d8 0x18adddcf8 0x18adddafc 0x18addddc4 0x18a7263e4 0x18a726360 0x18a70ec88 0x18a725c78 0x18a7258a8 0x18a71eadc 0x18a6efa2c 0x18a6edf18 0x1851505a4 0x185150038 0x18514dd38 0x18507cdc0 0x190518088 0x18a756f60 0x1000d56e4 0x19ae9e8b8)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb) 

Answer 1

您的 View 中可能有一个 socket 连接到类中未找到的标签 (SignUpLabel)。

您的文件所有者未设置为您的 ViewController，或者您已删除/重命名类中的标签，并且需要重置 View 中的导出。

您的约束也有错误，但这不会导致崩溃。