问题
I've to schedule a fixed task that check some info from internet at fixed interval timer.
Into Android, I use AlarmManager with setRepeating, but I'm newbie to iOS. There are some similar api that help me? I need a task that survive when app is killed by operating system.
Do you know a tutorial about it?
回答1:
AFAIK in iOS you cannot implement such service that will stay alive after its host app is killed, also only several types of applications can run some background tasks - see documentation here. You can do your task on server side and send push notification when you need users attention - if only user will allow your app to receive push notifications.
回答2:
Check link on Apple's Multitasking Guide that add's the voip tag to UIBackgroundModes in Info.plist and use setKeepAliveTimeout:handler: method of UIApplication to relaunch it if needed once the app is going to sleep.
Note : For this you need to take special permissions from Apple and mostly Apple rejects such app.
Another solution :-
You can store last sync date and if sync date has crossed your interval when application comes from background, you can start sync your data.
Hope this info helps you..
回答3:
You need local notifications of iOS
回答4:
I found that UILocalNotification was the best option for this. Unfortunately you cant trigger the app to open but you can get a notification to show up at a set interval.
https://developer.apple.com/library/ios/documentation/iPhone/Reference/UILocalNotification_Class/index.html#//apple_ref/doc/c_ref/UILocalNotification
回答5:
You may use NSBackgroundActivityScheduler to pull something periodically.
来源：https://stackoverflow.com/questions/14337275/ios-background-process-similar-to-android-alarmmanager