NSNotificationCenter的同步和异步

最新推荐文章于 2020-12-20 02:50:37 发布

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最新推荐文章于 2020-12-20 02:50:37 发布 · 5.6k 阅读

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文章标签：

#NSNotificationCenter #IOS

本文介绍了iOS开发中NSNotification的同步和异步处理方式，通过代码示例展示了如何在不同线程中执行通知事件处理，以及如何利用`performSelector:`和`performSelectorInBackground:`实现异步发送通知。

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];
    
    [[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 Fin