iOS通知（Notification）

- (IBAction)buttonClick:(id)sender {
    //添加 字典，将label的值通过key值设置传递
    NSDictionary *dict =[[NSDictionary alloc]initWithObjectsAndKeys:self.textFieldOne.text,@"textOne",self.textFieldTwo.text,@"textTwo",nil];
    //创建通知
    NSNotification *notification =[NSNotification notificationWithName:@"tongzhi" object:niluserInfo:dict];
    //通过通知中心发送通知
    [[NSNotificationCenter defaultCenter] postNotification:notification];
    [self.navigationController popViewControllerAnimated:YES];
 
}
在发送通知后，在所要接收的控制器中注册通知监听者，将通知发送的信息接收

- (void)viewDidLoad {
    [super viewDidLoad];
    //注册通知
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(tongzhi:)name:@"tongzhi" object:nil];
 
}
- (void)tongzhi:(NSNotification *)text{
    NSLog(@"%@",text.userInfo[@"textOne"]);
        NSLog(@"－－－－－接收到通知------");
 
}

移除通知：removeObserver:和removeObserver:name:object: