这很奇怪。我几乎没有使用该应用程序。只需修复约束，应用程序加载就很好，并且约束已生效。然后简单地我重新运行该应用程序并得到此错误。不知道如何解决。
First throw call stack:
(
0 CoreFoundation 0x000000010ea2673b __exceptionPreprocess + 331
1 libobjc.A.dylib 0x000000010da1b735 objc_exception_throw + 48
2 CoreFoundation 0x000000010ea26595 +[NSException raise:format:] + 197
3 QuartzCore 0x000000010ef8a923 _ZN2CA5Layer12set_positionERKNS_4Vec2IdEEb + 141
4 QuartzCore 0x000000010ef79a13 -[CALayer setPosition:] + 57
5 QuartzCore 0x000000010ef7a16f -[CALayer setFrame:] + 561
6 UIKitCore 0x0000000117ebf09e -[UIView(Geometry) setFrame:] + 336
7 List24 0x000000010d0c4364 $S6List2414ViewControllerC05tableB0_12cellForRowAtSo07UITableB4CellCSo0iB0C_10Foundation9IndexPathVtF + 836
8 List24 0x000000010d0c46bb $S6List2414ViewControllerC05tableB0_12cellForRowAtSo07UITableB4CellCSo0iB0C_10Foundation9IndexPathVtFTo + 155
9 UIKitCore 0x0000000117d38c1c -[UITableView _createPreparedCellForGlobalRow:withIndexPath:willDisplay:] + 771
10 UIKitCore 0x0000000117d391a9 -[UITableView _createPreparedCellForGlobalRow:willDisplay:] + 73
11 UIKitCore 0x0000000117d002aa -[UITableView _updateVisibleCellsNow:isRecursive:] + 2863
12 UIKitCore 0x0000000117d20f62 -[UITableView layoutSubviews] + 165
13 UIKitCore 0x0000000117ede749 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 1441
14 QuartzCore 0x000000010ef80299 -[CALayer layoutSublayers] + 175
15 QuartzCore 0x000000010ef85153 _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 395
16 QuartzCore 0x000000010eefdbb2 _ZN2CA7Context18commit_transactionEPNS_11TransactionE + 342
17 QuartzCore 0x000000010ef34e62 _ZN2CA11Transaction6commitEv + 576
18 UIKitCore 0x00000001177e1208 __34-[UIApplication _firstCommitBlock]_block_invoke_2 + 139
19 CoreFoundation 0x000000010e98a2bc __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK__ + 12
20 CoreFoundation 0x000000010e989a70 __CFRunLoopDoBlocks + 336
21 CoreFoundation 0x000000010e9842e4 __CFRunLoopRun + 1284
22 CoreFoundation 0x000000010e983aa1 CFRunLoopRunSpecific + 625
23 GraphicsServices 0x00000001142531dd GSEventRunModal + 62
24 UIKitCore 0x00000001177c6a4f UIApplicationMain + 140
25 List24 0x000000010d0d0f27 main + 71
26 libdyld.dylib 0x000000011116dced start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException