objective-c - NSWorkspaceDidTerminateApplicationNotification 崩溃

Question

所以我的一些用户遇到了崩溃，我认为我已经将其追踪到了 NSWorkspaceDidTerminateApplicationNotification，我根本无法重现崩溃，所以我不知道该去哪里？

这是生成的崩溃日志，也许我遗漏了一些明显的东西:

Exception Type:  EXC_BAD_ACCESS (SIGSEGV)
Exception Codes: KERN_INVALID_ADDRESS at 0x0000000000000010
Crashed Thread:  0  Dispatch queue: com.apple.main-thread

Application Specific Information:
objc_msgSend() selector name: invalidate


Thread 0 Crashed:  Dispatch queue: com.apple.main-thread
    0   libobjc.A.dylib                 0x00007fff816f211c objc_msgSend + 40
1   com.apple.Foundation            0x00007fff87ef58ea _nsnote_callback + 167
2   com.apple.CoreFoundation        0x00007fff869b3000 __CFXNotificationPost + 1008
3   com.apple.CoreFoundation        0x00007fff8699f578 _CFXNotificationPostNotification + 200
4   com.apple.Foundation            0x00007fff87eec84e -[NSNotificationCenter postNotificationName:object:userInfo:] + 101
5   com.apple.AppKit                0x00007fff878efb58 applicationStatusSubsystemCallback + 593
6   com.apple.LaunchServices        0x00007fff83523e6c LSScheduleNotificationReceiveMessageCallbackFunc(__CFMachPort*, void*, long, void*) + 184
7   com.apple.CoreFoundation        0x00007fff869cf68e __CFMachPortPerform + 366
8   com.apple.CoreFoundation        0x00007fff869a76e1 __CFRunLoopRun + 5201
9   com.apple.CoreFoundation        0x00007fff869a5dbf CFRunLoopRunSpecific + 575
10  com.apple.HIToolbox             0x00007fff80ef07ee RunCurrentEventLoopInMode + 333
11  com.apple.HIToolbox             0x00007fff80ef05f3 ReceiveNextEventCommon + 310
12  com.apple.HIToolbox             0x00007fff80ef04ac BlockUntilNextEventMatchingListInMode + 59
13  com.apple.AppKit                0x00007fff87232e64 _DPSNextEvent + 718
14  com.apple.AppKit                0x00007fff872327a9 -[NSApplication nextEventMatchingMask:untilDate:inMode:dequeue:] + 155
15  com.apple.AppKit                0x00007fff871f848b -[NSApplication run] + 395
16  com.apple.AppKit                0x00007fff871f11a8 NSApplicationMain + 364

这是相关代码:

NSNotificationCenter *center = [[NSWorkspace sharedWorkspace] notificationCenter];
[center addObserver:self selector:@selector(appTerminated:) name:NSWorkspaceDidTerminateApplicationNotification object:nil];

- (void)appTerminated:(NSNotification *)note
{
    NSString *app = [NSString stringWithFormat:@"%@", [[note userInfo] objectForKey:@"NSApplicationName"]];

    if ([app isEqualToString:Somestring])
        {       
            //do something here            
        }
    }
}

如果有人能给我一些关于去哪里寻找的指示，我将永远感激不已，我已经好几天了……

Answer 1

看起来您的窗口 Controller 正在被释放，同时仍在通知中心注册。您需要确保在释放之前窗口 Controller 未注册。否则，通知中心将尝试向已释放的对象发布通知，这可能会触发 EXC_BAD_ACCESS 异常。

例如，在您的窗口 Controller 实现中:

- (void)dealloc {
    [[[NSWorkspace sharedWorkspace] notificationCenter] removeObserver:self];
    [super dealloc];
}

这将针对在通知中心注册的每个通知注销窗口 Controller 。