采用 UIWebView 实现 hybrid 方案过程中，遇到过一些 crash，刚开始遇到的时候感觉特别诡异，这里整理一下，方便今后查阅。
unrecognized selector
Application Specific Information:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIWebView paste:]: unrecognized selector sent to instance 0x110f35fc0'
Last Exception Backtrace:
0 CoreFoundation ___exceptionPreprocess
1 libobjc.A.dylib _objc_exception_throw
2 CoreFoundation ___methodDescriptionForSelector
3 CoreFoundation ____forwarding___
4 CoreFoundation __CF_forwarding_prep_0
5 UIKit -[UICalloutBar buttonPressed:]
6 UIKit -[UICalloutBarButton fadeAndSendAction]
7 Foundation ___NSFireDelayedPerform
8 CoreFoundation ___CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__
9 CoreFoundation ___CFRunLoopDoTimer
10 CoreFoundation ___CFRunLoopDoTimers
11 CoreFoundation ___CFRunLoopRun
12 CoreFoundation _CFRunLoopRunSpecific
13 GraphicsServices _GSEventRunModal
14 UIKit _UIApplicationMain
15 OneTravel main main.m:14
16 libdyld.dylib _start
发现这个 crash 的时候，简直丈二和尚——摸不着头脑，整个项目压根就没有调用过这以为方法啊，抓狂了一会儿，立马想到了 Stack Overflow。于是找到了这个：
原来如此，Apple 的坑，按照 ac 的 Answer 方案进行修复即可~今后再遇到如下 UIWebView 的 unrecognized selector，就知道如何处理了：
"cut:", "copy:", "paste:","select:", "selectAll:", "delete:", "makeTextWritingDirectionLeftToRight:", "makeTextWritingDirectionRightToLeft:", "toggleBoldface:", "toggleItalics:", "toggleUnderline:", "increaseSize:", "decreaseSize:"
