1.应用生命周期

Not running 非运行状态Not running  →  Inactive → Active  →  Background → Suspended 

Inactive  前台非活动状态

Active 前台活动状态

Background 后台状态

Suspended 挂起状态

非运行状态——应用启动情景

Not running → Inactive → Active

        Not Running → Inactive    调用appliaction：didiFinishLaunchingWithOptions：方法

                                               发出UIApplicationDidFinshLanuchingNotification通知

        Inactive → Active              调用applicationDidBecomeActive：方法

                                                发出UIApplicationDidBecomeActiveNotification通知

点击Home键——应用退出情景

应用可以在后台运行或者挂起

Active  →  Inactive → Background → Suspended

        Active  →  Inactive             调用applicationWillResignActive发：方法    

                                                发出UIApplicationWillResignActiveNotification通知

       Background → Suspended     调用applicationDidEnterBackground：方法

                                                 发出UIApplicationDidEnterBackgroundNotification通知

    应用不可以在后台运行或者挂起

Active  →  Inactive → Background → Suspended →  Not running 

      Background → Suspended         调用applicationDidEnterBackground：方法    

                                                    发出UIApplicationDidEnterBackgroundNotification通知

      Suspended →  Not running        调用applicationWillTerminate：方法

                                                    发出UIApplicationWillTerminateNotification通知    

 挂起重新运行情景

Suspended  → Background  →  Inactive → Active

    Background →  Inactive        调用applicationWiillEnterForeground：方法

                                               发出UIApplicationWiillEnterForegroundNotification通知

    nactive→Active                     调用applicationDidBecomeActive：方法

                                               发出UIApplicationDidBecomeActiveNotification通知

内存清除——应用终止情景

在内存清除场景侠，应用不会调用任何方法，也不会发出应用通知

2.视图生命周期

1.生命周期

原文：http://my.oschina.net/u/2346786/blog/413045