a objective-c class that bridge CFNotification between NSNotification

DarwinNotificationBridge.m

// DarwinNotificationBridge.h
@interface DarwinNotificationBridge: NSObject
+ (instancetype)startBridgeForTarget:(id)target andSelector:(SEL)selector forName:(NSString *)name;
+ (void) postNotification:(NSString *)name withUserInfo:(NSDictionary *)userInfo;

- (instancetype)initWithTarget:(id)target andSelector:(SEL)selector forName:(NSString *)name;
- (void)start;
- (void)stop;
@end

// DarwinNotificationBridge.m
static void onDarwinNotification(CFNotificationCenterRef center, void *observer,
                                             CFStringRef name, const void *object, CFDictionaryRef userInfo) {
    NSDictionary *nsUserInfo = (__bridge_transfer NSDictionary *)userInfo;
    id nsObject = (__bridge_transfer id)object;
    NSString *nsName = (__bridge_transfer NSString *)name;
    
    NSNotification *noti = [NSNotification notificationWithName:nsName object:nsObject userInfo:nsUserInfo];
    DarwinNotificationBridge *receiver = (__bridge DarwinNotificationBridge*)observer;
    
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, NSEC_PER_MSEC*100), dispatch_get_main_queue(), ^{   // it maybe crash if no delay here.
        [receiver performSelector:@selector(dispatchNotification:) withObject:noti];
    });
}

@implementation DarwinNotificationBridge {
    __weak id _target;
    SEL _selector;
    NSString *_name;
    CFTypeRef _cfSelf;
}

+ (instancetype)startBridgeForTarget:(id)target andSelector:(SEL)selector forName:(NSString *)name {
    DarwinNotificationBridge *instance = [[self alloc] initWithTarget:target andSelector:selector forName:name];
    [instance start];
    return instance;
}

- (instancetype)initWithTarget:(id)target andSelector:(SEL)selector forName:(NSString *)name {
    self = [super init];
    if (self) {
        _target = target;
        _selector = selector;
        _name = name;
    }
    return self;
}

- (void)start {
    if (_cfSelf != NULL) return;
    
    _cfSelf = CFRetain((__bridge void *)self);
    CFNotificationCenterAddObserver(CFNotificationCenterGetDarwinNotifyCenter(), _cfSelf,
                                    onDarwinNotification, (__bridge_retained CFStringRef)_name,
                                    NULL, CFNotificationSuspensionBehaviorDeliverImmediately);
}

- (void)stop {
    if (_cfSelf == NULL) return;
    
    CFNotificationCenterRemoveEveryObserver(CFNotificationCenterGetDarwinNotifyCenter(), _cfSelf);
    CFRelease(_cfSelf);
    _cfSelf = NULL;
}

- (void)dispatchNotification:(NSNotification *)notification {
    if ([_target respondsToSelector:_selector]) {
        [_target performSelector:_selector withObject:notification];
    }
}

+ (void)postNotification:(NSString *)name withUserInfo:(NSDictionary *)userInfo {
    CFNotificationCenterPostNotification(CFNotificationCenterGetDarwinNotifyCenter(), (__bridge_retained CFStringRef)name,
                                         NULL, (__bridge_retained CFDictionaryRef)userInfo, YES);
}
@end