尝试调用这个方法：
avatarIconImageView.setContentHuggingPriority(UILayoutPriorityDefaultLow,forAxis: UILayoutConstraintAxis.Horizontal)
并捕获此异常：
Undefined symbols for architecture armv7:
“_UILayoutPriorityDefaultLow”,referenced from:
__TFC13TCProject_iOS36TCAvatarWithCounterUniversalCellView22configureBodyCellViewsfS0_FT_T_
in TCAvatarUniversalCellView.o ld: symbol(s) not found for
architecture armv7 clang: error: linker command Failed with exit code
1 (use -v to see invocation)
这是什么意思？
解决方法
这看起来像iOS 8 SDK中的错误.您可以通过传递原始值来解决此问题.
> UILayoutPriorityDefaultrequired = 1000
> UILayoutPriorityDefaultHigh = 750
> UILayoutPriorityDefaultLow = 250
在你的情况下
avatarIconImageView.setContentHuggingPriority(250,forAxis: UILayoutConstraintAxis.Horizontal)