NSNotificationCenter

- (void)viewDidLoad {

    [super viewDidLoad];

    

    UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];

    btn.frame = CGRectMake(100, 100, 100, 50);

    btn.backgroundColor = [UIColor grayColor];

    [btn setTitle:@"click me" forState:UIControlStateNormal];

    [btn addTarget:self action:@selector(clickAction:) forControlEvents:UIControlEventTouchUpInside];

    

    [self.view addSubview:btn];

    

    // 注册消息

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(handleNoticeMessage:) name:@"test" object:@"notice-recieve"];

}

 

-(void)clickAction:(id)sender

{

    // 能接受消息

    [[NSNotificationCenter defaultCenter] postNotificationName:@"test" object:@"notice-recieve"];

    

    // 不能接收到消息，object 对象不一致

    [[NSNotificationCenter defaultCenter] postNotificationName:@"test" object:@"notice-recieve111"];

}

 

// 处理消息

-(void)handleNoticeMessage:(id)sender

{

    NSLog(@"handleNoticeMessage sender = %@", sender);

}

 

-(void)viewWillDisappear:(BOOL)animated

{

    // 移除通知

    [[NSNotificationCenter defaultCenter]removeObserver:self];

}