很多时候,当我尝试在情节提要中编辑 UILabel 时,Xcode 会崩溃。有什么想法可能导致这种情况吗?看起来它与自动布局约束之一有关。这是错误报告:
Process: Xcode [43938]
Path: /Applications/Xcode.app/Contents/MacOS/Xcode
Identifier: com.apple.dt.Xcode
Version: 4.5 (1839)
Build Info: IDEApplication-1839000000000000~3
App Item ID: 497799835
App External ID: 10747437
Code Type: X86-64 (Native)
Parent Process: launchd [43283]
Date/Time: 2012-10-01 09:43:36.443 -0400
OS Version: Mac OS X 10.7.4 (11E53)
Report Version: 9
Sleep/Wake UUID: 8C7C93A7-0BEF-42C6-944C-488D8C7896DD
Interval Since Last Report: 152594 sec
Crashes Since Last Report: 6
Per-App Interval Since Last Report: 135715 sec
Per-App Crashes Since Last Report: 5
Anonymous UUID: E745D8FE-362B-4FD2-8594-7EC5C26767B2
Crashed Thread: 0 Dispatch queue: com.apple.main-thread
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Application Specific Information:
ProductBuildVersion: 4G182
ASSERTION FAILURE in /SourceCache/IDEInterfaceBuilderCocoaTouch/IDEInterfaceBuilderCocoaTouch-1926/IBPlugin/Utilities/IBObjectMarshalling.m:651
Details: Failed to start deciding frames for IBNSLayoutConstraint, IBUILabel, IBUITabBarItem, IBUITableView, IBUIView, and IBUIViewController.
Interface Builder encountered an error communicating with the iOS Simulator. If you choose to file a crash report or radar for this issue, please check Console.app for crash reports for "Interface Builder Cocoa Touch Tool" and include their content in your crash report.
Exception name: IBAssertionFailure
Exception reason: ASSERTION FAILURE: realConstraint
Reason: Should have found real constraint for represented constraint <NSLayoutConstraint:0x86a8c30 H:[UIView:0x868a0f0(71)]>
File: /SourceCache/IBAutolayoutFoundationIOS/IBAutolayoutFoundation-1818/Framework/Classes/Arbitration/IBAutolayoutEngine.m:223
Method: __76-[IBAutolayoutEngine realConstraintsFromCollectionOfRepresentedConstraints:]_block_invoke_0
Exception backtrace:
0. CoreFoundation 0x022a4012 __exceptionPreprocess
1. libobjc.A.dylib 0x01703e7e objc_exception_throw
2. CoreFoundation 0x0232cfb1 -[NSException raise]
3. ??? 0x0000beae [IBCocoaTouchTool startAutolayoutFrameDecisionSessionWithRequest:document:]
4. ??? 0x000342a5 [IBMessageReceiveChannel deliverMessage:toTarget:withArguments:result:]
5. ??? 0x00033fa9 [IBMessageReceiveChannel deliverMessage:toTarget:withArguments:result:]
6. ??? 0x00033c47 [IBMessageReceiveChannel runBlockingReceiveLoopNotifyingQueue:notifyingTarget:]
7. libdispatch.dylib 0x04c3d731 _dispatch_barrier_sync_f_slow_invoke
8. libdispatch.dylib 0x04c4c014 _dispatch_client_callout
9. libdispatch.dylib 0x04c3c7d5 _dispatch_main_queue_callback_4CF
10. CoreFoundation 0x0224aaf5 __CFRunLoopRun
11. CoreFoundation 0x02249f44 CFRunLoopRunSpecific
12. CoreFoundation 0x02249e1b CFRunLoopRunInMode
13. Foundation 0x01308c7c -[NSRunLoop(NSRunLoop) runMode:beforeDate:]
14. ??? 0x0000cf06 [IBCocoaTouchTool startServingReceiveChannel:]
15. ??? 0x0000d09f [IBCocoaTouchTool startServingWithSocket:]
16. ??? 0x0000e1b7 [IBCocoaTouchTool .cxx_destruct]
17. ??? 0x00002365 ???
Exception info:{
}