ios 监听app从后台恢复到前台

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博文原创，转载请声明出处

电子咖啡(原id蓝岩)

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正常情况下，在AppDelegate中实现下面两个方法，能够监听从后台恢复到前台

- (void)applicationDidEnterBackground:(UIApplication *)application
{
    log4info(@"---applicationDidEnterBackground----");
   //进入后台
}

- (void)applicationDidBecomeActive:(UIApplication *)application
{

    NSLog(@"---applicationDidBecomeActive----");
    //进入前台

    
}

但是单个UIViewController怎么监听呢

在-viewDidLoad方法中，添加一下代码监听notification

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(someMethod:)
                                             name:UIApplicationDidBecomeActiveNotification object:nil];

别忘了在-dealloc中将监听移除：

[[NSNotificationCenter defaultCenter] removeObserver:self];