NSNotificationQueue多线程

标签：nsnotificationqueue   ios   

首先上代码：

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button setFrame:CGRectMake(0, 0, 400, 60)];
    [button addTarget:self action:@selector(buttonDown) forControlEvents:UIControlEventTouchUpInside];
    [button setTitle:@"Post Notification" forState:UIControlStateNormal];
    [self.view addSubview:button];
    
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    
        [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(actionNotification:)
                                                     name:kNotificationName object:nil];
        
    });
    
}

- (void) actionNotification: (NSNotification*)notification
{
    
    NSString* message = notification.object;
    NSLog(@"%@",message);
    
    sleep(5);
    
    NSLog(@"Action Notification Finish");
    
}

- (void)buttonDown
{
    
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        
        NSNotification *notification = [NSNotification notificationWithName:kNotificationName
                                                                     object:@"object"];
        [[NSNotificationQueue defaultQueue] enqueueNotification:notification
                                                   postingStyle:NSPostASAP];
        
    });
    
    NSLog(@"buttonDown");
    
}

打印信息如下：

2015-03-17 18:47:20.131 AppTest[19507:206469] buttonDown

也就是说，观察者们和poster有可能都在不同的子线程中，这样观察者们就收不到通知事件，

这里有个解决方法是把通知队列放主线程中去；

还有个解决方法就是把NSPostASAP改为NSPostNow。

NSNotificationQueue多线程

标签：nsnotificationqueue   ios   

原文地址：http://blog.csdn.net/junjun150013652/article/details/44346023