ios 監聽app從後台恢複到前台

============================================================博文原創，轉載請聲明出處電子咖啡(原id藍岩)============================================================

正常情況下，在AppDelegate中實現下面兩個方法，能夠監聽從後台恢複到前台

- (void)applicationDidEnterBackground:(UIApplication *)application{    log4info(@"---applicationDidEnterBackground----");   //進入後台}- (void)applicationDidBecomeActive:(UIApplication *)application{    NSLog(@"---applicationDidBecomeActive----");    //進入前台    }

但是單個UIViewController怎麼監聽呢

在-viewDidLoad方法中，添加一下代碼監聽notification

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

別忘了在-dealloc中將監聽移除：

[[NSNotificationCenter defaultCenter] removeObserver:self];