iphone - 监听所有 CFNotifications？

Question

我正在编写一个小测试程序，可以在其中查看 iOS 设备上发生各种操作时发布的所有通知。不幸的是，我遇到了一个问题，当我尝试向 Darwin 通知中心添加观察者时，我收到 EXC_BAD_ACCESS 错误。相关代码如下:

void callback(CFNotificationCenterRef center, void *observer, CFStringRef name, const void *object, CFDictionaryRef userInfo) {  
    NSNotification* n = [NSNotification notificationWithName:name object:object userInfo:userInfo];

    objc_msgSend(gSelf, sel_getUid(@"note:"), n);
    return;  
}  


- (void)viewDidLoad {
    [super viewDidLoad];
    gSelf = self;
    notifications = [[NSMutableArray alloc] initWithCapacity:10];
    self.title = @"Notification Log";

    CFNotificationCenterAddObserver(  
                                    CFNotificationCenterGetDarwinNotifyCenter(), //center  
                                    NULL, // observer  
                                    callback, // callback  
                                    NULL, // name  
                                    NULL, // object  
                                    CFNotificationSuspensionBehaviorHold  
                                    );   
}

-(void)note:(NSNotification *)notification{

    @synchronized(self){
        [notifications addObject:notification];
        [self.tableView reloadData];
    }
}

Answer 1

来自 CFNotificationCenter.h:(查找 CFNotificationCenterGetDarwinNotifyCenter 的定义。)或 the CFNotificationCenter reference

CFNotificationCenterAddObserver(): the 'name' argument may not be NULL (for this center).