NSTextField 绑定导致 EXC_BAD_ACCESS

Question

我有一个 NSTextField，它绑定到我包含在笔尖中的对象中的 int 。当对象更改其 int 时，文本字段也会随之更改，一切看起来都很好。

但是，当我尝试手动更改它时，一旦按下某个键，程序就会崩溃。它甚至没有进入我的 setter 方法，它只是崩溃了

Program received signal:  “EXC_BAD_ACCESS”.

It's not甚至在我的任何代码中......大概，我做了错误的绑定，但我能做什么，会使其出现这样的段错误？

ETA：崩溃时的堆栈帧：

Process:         DocKeep [77998]
Path:            /Users/acordex/Documents/projects/DocKeep/build/Debug/DocKeep.app/Contents/MacOS/DocKeep
Identifier:      com.acordex.DocKeep
Version:         9.00 pre-Alpha (9.00 pre-Alpha)
Code Type:       X86 (Native)
Parent Process:  Instruments [77954]

Date/Time:       2010-07-29 10:01:11.927 -0400
OS Version:      Mac OS X 10.6.4 (10F569)
Report Version:  6

Exception Type:  EXC_BAD_ACCESS (SIGBUS)
Exception Codes: KERN_PROTECTION_FAILURE at 0x000000000000001c
Crashed Thread:  0  Dispatch queue: com.apple.main-thread

Thread 0 Crashed:  Dispatch queue: com.apple.main-thread
0   com.apple.AppKit                0x954a4734 -[NSDocument(NSEditorRegistration) _isBeingEdited] + 24
1   com.apple.AppKit                0x954a4707 -[NSDocument isDocumentEdited] + 47
2   com.apple.AppKit                0x955b3900 -[NSDocument(NSEditorRegistration) objectDidBeginEditing:] + 48
3   com.apple.AppKit                0x95461ef9 -[NSValueBinder _startChanging] + 126
4   com.apple.AppKit                0x95461dc1 -[NSTextValueBinder _startChanging] + 60
5   com.apple.AppKit                0x95461d5f -[_NSBindingAdaptor _editor:didChangeEditingState:bindingAdaptor:] + 181
6   com.apple.AppKit                0x95461c9f -[_NSBindingAdaptor editorDidBeginEditing:] + 278
7   com.apple.AppKit                0x95442e5a -[NSTextField textShouldBeginEditing:] + 239
8   com.apple.AppKit                0x95441d0b -[NSTextView(NSSharing) shouldChangeTextInRanges:replacementStrings:] + 573
9   com.apple.AppKit                0x95464563 _NSDoUserReplaceForCharRange + 191
10  com.apple.AppKit                0x9546449e _NSDoUserDeleteForCharRange + 79
11  com.apple.AppKit                0x95463b07 -[NSTextView(NSKeyBindingCommands) deleteBackward:] + 684
12  com.apple.AppKit                0x9544b364 -[NSResponder doCommandBySelector:] + 77
13  com.apple.AppKit                0x9544ac7f -[NSTextView doCommandBySelector:] + 240
14  com.apple.AppKit                0x95439bbf -[NSKeyBindingManager(NSKeyBindingManager_MultiClients) interpretEventAsCommand:forClient:] + 1911
15  com.apple.AppKit                0x9543d44f -[NSTextInputContext handleEvent:] + 1604
16  com.apple.AppKit                0x95439229 -[NSView interpretKeyEvents:] + 209
17  com.apple.AppKit                0x9543ccd5 -[NSTextView keyDown:] + 751
18  com.apple.AppKit                0x9536df6c -[NSWindow sendEvent:] + 5757
19  com.apple.AppKit                0x95286aff -[NSApplication sendEvent:] + 6431
20  com.apple.AppKit                0x9521a5bb -[NSApplication run] + 917
21  com.apple.AppKit                0x952125ed NSApplicationMain + 574
22  com.acordex.DocKeep             0x0000224c main + 30 (main.m:14)
23  com.acordex.DocKeep             0x00002202 start + 54

Thread 1:
0   libSystem.B.dylib               0x94a319d2 __workq_kernreturn + 10
1   libSystem.B.dylib               0x94a31f68 _pthread_wqthread + 941
2   libSystem.B.dylib               0x94a31b86 start_wqthread + 30

Thread 2:  Dispatch queue: com.apple.libdispatch-manager
0   libSystem.B.dylib               0x94a32942 kevent + 10
1   libSystem.B.dylib               0x94a3305c _dispatch_mgr_invoke + 215
2   libSystem.B.dylib               0x94a32519 _dispatch_queue_invoke + 163
3   libSystem.B.dylib               0x94a322be _dispatch_worker_thread2 + 240
4   libSystem.B.dylib               0x94a31d41 _pthread_wqthread + 390
5   libSystem.B.dylib               0x94a31b86 start_wqthread + 30

Thread 3:
0   libSystem.B.dylib               0x94a3a066 __semwait_signal + 10
1   libSystem.B.dylib               0x94a39d22 _pthread_cond_wait + 1191
2   libSystem.B.dylib               0x94a3b9b8 pthread_cond_wait$UNIX2003 + 73
3   com.apple.CoreVideo             0x96730c3e CVDisplayLink::runIOThread() + 1016
4   com.apple.CoreVideo             0x9673082a startIOThread(void*) + 156
5   libSystem.B.dylib               0x94a3981d _pthread_start + 345
6   libSystem.B.dylib               0x94a396a2 thread_start + 34

Thread 0 crashed with X86 Thread State (32-bit):
  eax: 0x00000000  ebx: 0x954a472d  ecx: 0x00000001  edx: 0x00000000
  edi: 0x0045f650  esi: 0x0045f650  ebp: 0xbfffe738  esp: 0xbfffe720
   ss: 0x0000001f  efl: 0x00010282  eip: 0x954a4734   cs: 0x00000017
   ds: 0x0000001f   es: 0x0000001f   fs: 0x00000000   gs: 0x00000037
  cr2: 0x0000001c

我确实有一个文档类，它是NSDocument的子类，并且文本字段绑定到该文档对象的字段，但我'我不确定为什么这很重要。

Answer 1

环境变量 NSBindingDebugLogLevel 可能有用。设置它并仔细检查日志中是否有警告。如果您在 NSException 引发时设置了断点，您可能不会看到警告。

绑定应该与 int 一起使用，绝对不能与 unsigned int 一起使用。但 NSTextfield 需要一个 NSString，或者至少需要一个 NSNumber 和一个关联的 NSNumberFormatter。