Lack of API to determine when app extension has entered background or foreground

Originator:davidz
Number:rdar://18067636 Date Originated:August 19, 2014
Status:Duplicate Resolved:Dupe: 17832582 (Open)
Product:iOS SDK Product Version:8.0b5
Classification: Reproducible:Yes
 
Summary:
UIApplication provides several notifications to notify apps of lifecycle changes, e.g. UIApplicationWillEnterForegroundNotification, UIApplicationDidEnterBackgroundNotification. However, none of these notifications can be observed from an app extension (specifically, a Document Picker), and there do not seem to be any alternatives that work from within an app extension.

One use case is to acquire/release locks on entering/leaving foreground. Since an extension can run as multiple processes concurrently, it is important to synchronize data accesses between them.

Steps to Reproduce:
1. Read through iOS 8 SDK and API documentation to find a notification or callback that occurs when the app extension's host app is put into foreground or background.

Expected Results:
1. Find some API that allows the app extension to observe lifecycle state changes.

Actual Results:
1. Find no such API, return home very sad.

Version:
iOS 8.0  (12A4345d)

Notes:


Configuration:
iPhone

Comments


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