点击输入框有时候崩溃

-: unrecognized selector sent to instance 0x126535120
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libobjc.A.dylib 0x0000000195c8fbd0 objc_msgSend + 16
1 UIKit 0x0000000188ea86dc - + 108
2 UIKit 0x0000000188e8ba70 - + 20
3 UIKit 0x0000000188e8ba44 - + 20
4 UIKit 0x0000000188e8ba18 - + 28
5 UIKit 0x00000001895c65cc - + 28
6 CoreFoundation 0x00000001843f62c0 __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 16
7 CoreFoundation 0x000000018433344c _CFXNotificationPost + 2056
8 Foundation 0x0000000185262a7c - + 68
9 UIKit 0x000000018958fe2c - + 576
10 UIKit 0x000000018958e390 - + 148
11 UIKit 0x0000000189591ac0 __77-_block_invoke644 + 460
12 UIKit 0x0000000188ec8770 - + 404
13 UIKit 0x0000000188ec82d8 - + 184
14 UIKit 0x0000000188ec81e0 - + 100