NSNotificationCenter 用法

下面是编程之家 jb51.cc 通过网络收集整理的代码片段。

编程之家小编现在分享给大家，也给大家做个参考。

@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

//... somewhere else in another class ...
- (void) someMethod
{
    // All instances of TestClass will be notified
    [[NSNotificationCenter defaultCenter] 
        postNotificationName:@"TestNotification"
        object:self];
}

以上是编程之家(jb51.cc)为你收集整理的全部代码内容，希望文章能够帮你解决所遇到的程序开发问题。

如果觉得编程之家网站内容还不错，欢迎将编程之家网站推荐给程序员好友。