问题
in both, 1) iPhone goes in Sleep mode 2) Open notification Center
It calls
- (void)applicationWillResignActive:(UIApplication *)application
Is there any way to identify if this method is called because device went in to sleep mode or by opening notification center?
回答1:
There are some hacks to detect lock/unlock, but nothing official that couldn't break with a future iOS release.
回答2:
OK, When you lock your screen/iPhone goes to sleep mode, the front most app(Your app) will go to background mode, and when you pull down the Notification Center, you app actually is not pushed to background.
So, you can use
- (void)applicationWillEnterForeground:(UIApplication *)application
or
- (void)applicationDidEnterBackground:(UIApplication *)application
to set a value, say bgFlag, in your app delegate class,
then, when - (void)applicationDidBecomeActive:(UIApplication *)application is invoked, you check whether bgFlag is set or not.
Good luck.
来源：https://stackoverflow.com/questions/9060066/sleep-mode-vs-notification-center-open