这个在8.1的系统下会崩溃噢

[Jdb156158]

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'An instance 0x7fe54e163370 of class UIView was deallocated while key value observers were still registered with it. Current observation info: <NSKeyValueObservationInfo 0x7fe54e12ffe0> (
<NSKeyValueObservance 0x7fe54bef76d0: Observer: 0x7fe54e1594e0, Key path: frame, Options: <New: YES, Old: YES, Prior: NO> Context: 0x0, Property: 0x7fe54e163440>
<NSKeyValueObservance 0x7fe54e15

[zhaoName]

找到问题是在iOS8.1模拟器下，- (void)layoutSubviews会调用两边，导致KVO走两次

但是在共同努力下问题没有解决，等待。。。