在使用Masonry时候，有时候虽然界面显示正常，但是log里面会出现如下类似的警告。

一.问题描述：

[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. 

[

<MASLayoutConstraint:0x600002e4db00 UIImageView:0x7f8510f5ec00.left == OTCMyHeaderView:0x7f8510d11da0.left + 14>,

<MASLayoutConstraint:0x600002e4db60 UIImageView:0x7f8510f5ec00.right == OTCMyHeaderView:0x7f8510d11da0.right - 14>,

<NSLayoutConstraint:0x600002962080 OTCMyHeaderView:0x7f8510d11da0.width == 0>

]

Will attempt to recover by breaking constraint 

<MASLayoutConstraint:0x600002e4db60 UIImageView:0x7f8510f5ec00.right == OTCMyHeaderView:0x7f8510d11da0.right - 14>

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.

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二. 解决方法：

1.通过断点找到有问题的控件XX

2. 初始化控件XX 下面 添加 代码   MASAttachKeys(控件XX)

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3.run，看log

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一目了然就可以看到有问题的约束，修改即可。