Objective-C의 NSNotificationCenter를 통해 메시지를 보내고 받습니까?

Objective-C의 NSNotificationCenter를 통해 메시지를 보내고 받습니까?

메시지 송수신을 시도하고 있습니다.NSNotificationCenter목적-C.하지만 어떻게 해야 하는지 예시를 찾을 수 없었습니다.메시지 송수신은 어떻게 합니까?NSNotificationCenter?

@implementation TestClass

- (void) dealloc
{
    // If you don't remove yourself as an observer, the Notification Center
    // will continue to try and send notification objects to the deallocated
    // object.
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    [super dealloc];
}

- (id) init
{
    self = [super init];
    if (!self) return nil;

    // Add this instance of TestClass as an observer of the TestNotification.
    // We tell the notification center to inform us of "TestNotification"
    // notifications using the receiveTestNotification: selector. By
    // specifying object:nil, we tell the notification center that we are not
    // interested in who posted the notification. If you provided an actual
    // object rather than nil, the notification center will only notify you
    // when the notification was posted by that particular object.

    [[NSNotificationCenter defaultCenter] addObserver:self
        selector:@selector(receiveTestNotification:) 
        name:@"TestNotification"
        object:nil];

    return self;
}

- (void) receiveTestNotification:(NSNotification *) notification
{
    // [notification name] should always be @"TestNotification"
    // unless you use this method for observation of other notifications
    // as well.

    if ([[notification name] isEqualToString:@"TestNotification"])
        NSLog (@"Successfully received the test notification!");
}

@end

...다른 반의 어딘가에서...

- (void) someMethod
{

    // All instances of TestClass will be notified
    [[NSNotificationCenter defaultCenter] 
        postNotificationName:@"TestNotification" 
        object:self];

}

드림락스의 예를 들어 설명하자면...통지와 함께 데이터를 전송하려는 경우

게시 코드:

NSDictionary *userInfo = 
[NSDictionary dictionaryWithObject:myObject forKey:@"someKey"];
[[NSNotificationCenter defaultCenter] postNotificationName: 
                       @"TestNotification" object:nil userInfo:userInfo];

코드를 준수할 때:

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

    NSDictionary *userInfo = notification.userInfo;
    MyObject *myObject = [userInfo objectForKey:@"someKey"];
}

이것이 도움이 되었습니다.

// Add an observer that will respond to loginComplete
[[NSNotificationCenter defaultCenter] addObserver:self 
                                             selector:@selector(showMainMenu:) 
                                                 name:@"loginComplete" object:nil];


// Post a notification to loginComplete
[[NSNotificationCenter defaultCenter] postNotificationName:@"loginComplete" object:nil];


// the function specified in the same class where we defined the addObserver
- (void)showMainMenu:(NSNotification *)note {
    NSLog(@"Received Notification - Someone seems to have logged in"); 
}

출처 : http://www.smipple.net/snippet/Sounden/Simple%20NSNotificationCenter%20example

또한 블록을 사용할 수도 있습니다.

NSOperationQueue *mainQueue = [NSOperationQueue mainQueue];
[[NSNotificationCenter defaultCenter] 
     addObserverForName:@"notificationName" 
     object:nil
     queue:mainQueue
     usingBlock:^(NSNotification *notification)
     {
          NSLog(@"Notification received!");
          NSDictionary *userInfo = notification.userInfo;

          // ...
     }];

애플의 문서

NSNotificationCenter를 사용하여 보기를 업데이트하려는 경우, 메인 스레드에서 다음 주소로 전화하여 전송하는 것을 잊지 마십시오.dispatch_async:

dispatch_async(dispatch_get_main_queue(),^{
    [[NSNotificationCenter defaultCenter] postNotificationName:@"my_notification" object:nil];
});

신입사원 대상 답변의 SWIFT 5.1

class TestClass {
    deinit {
        // If you don't remove yourself as an observer, the Notification Center
        // will continue to try and send notification objects to the deallocated
        // object.
        NotificationCenter.default.removeObserver(self)
    }

    init() {
        super.init()

        // Add this instance of TestClass as an observer of the TestNotification.
        // We tell the notification center to inform us of "TestNotification"
        // notifications using the receiveTestNotification: selector. By
        // specifying object:nil, we tell the notification center that we are not
        // interested in who posted the notification. If you provided an actual
        // object rather than nil, the notification center will only notify you
        // when the notification was posted by that particular object.

        NotificationCenter.default.addObserver(self, selector: #selector(receiveTest(_:)), name: NSNotification.Name("TestNotification"), object: nil)
    }

    @objc func receiveTest(_ notification: Notification?) {
        // [notification name] should always be @"TestNotification"
        // unless you use this method for observation of other notifications
        // as well.

        if notification?.name.isEqual(toString: "TestNotification") != nil {
            print("Successfully received the test notification!")
        }
    }
}

...다른 반의 어딘가에서...

 func someMethod(){
        // All instances of TestClass will be notified
        NotificationCenter.default.post(name: NSNotification.Name(rawValue: "TestNotification"), object: self)
 }

언급URL : https://stackoverflow.com/questions/2191594/send-and-receive-messages-through-nsnotificationcenter-in-objective-c