关于AppDelegate里面的那些函数方法

//启动基本完成程序准备开始运行.- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    return YES;}//当应用程序将要进入非活动状态.在此期间，应用程序不接收消息或事件，比如来电话了.- (void)applicationWillResignActive:(UIApplication *)application {}//当程序被推送到后台的时候调用。所以要设置后台继续运行，则在这个函数里面设置即可.- (void)applicationDidEnterBackground:(UIApplication *)application {}//当程序从后台将要重新回到前台时候调用.- (void)applicationWillEnterForeground:(UIApplication *)application {}//当应用程序入活动状态执行.- (void)applicationDidBecomeActive:(UIApplication *)application {}//当程序将要退出是被调用，通常是用来保存数据和一些退出前的清理工作。这个需要要设置UIApplicationExitsOnSuspend的键值。- (void)applicationWillTerminate:(UIApplication *)application {}//请求委托打开一个 URL资源- (BOOL) application:(UIApplication *) application handleOpenURL:(NSURL *)url{}//请求委托打开一个 URL资源- (BOOL) application:(UIApplication *) application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation{}//当内存低告警时- (void)applicationDidReceiveMemoryWarning:(UIApplication *)application{}//当系统时间发生显著改变时-(void)applicationSignificantTimeChange:(UIApplication *)application{}//当一个运行着的应用程序收到一个远程的通知 发送到委托去...7.0之前- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo{}//当一个运行着的应用程序收到一个远程的通知 发送到委托去...7.0之后- (void)application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler{}//当一个应用程序成功的注册一个推送服务（APS） 发送到委托去...-(void) application :(UIApplication *) application didRegisterForRemoteNotificationsWithDeviceToken:(NSData *) deviceToken{}//当 APS无法成功的完成向 程序进程推送时 发送到委托去..-(void) application :(UIApplication *) application didFailToRegisterForRemoteNotificationsWithError:(NSError *) error{}//当一个运行着的应用程序收到一个本地的通知 发送到委托去...-(void) application :(UIApplication *) application didReceiveLocalNotification:(UILocalNotification *)notification{}