When should I store and re-store the keychain on ios swift?

Question

I see several methods in appDelegate, and I'm not sure if saving and re-saving user state only in some of them covers all scenarios?

func applicationWillResignActive(application: UIApplication) {
    // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
    // Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.

    stopTasks()
    setSharedPrefrences()
}

func applicationDidEnterBackground(application: UIApplication) {
    // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
    // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.

    stopTasks()
    setSharedPrefrences()
}

func applicationWillEnterForeground(application: UIApplication) {
    // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.

    startTasks()
    getSharedPrefrences()
}

func applicationDidBecomeActive(application: UIApplication) {
    // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
    startTasks()
    getSharedPrefrences()
    connectGcmService(application)

}

func applicationWillTerminate(application: UIApplication) {
    // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:.
    stopTasks()
    setSharedPrefrences()
    disconnectGcmService(application)
}

Should only some of them be stored / restored? When should I disconnect and connect to the GCM service?

Is my recovery redundant?

Saving a local flag talking about recovery is not practical, since the application can destroy it?

Answer 1

Read about the Application Life Cycle: Application Runtimes in the Apple Application Programming Guide for iOS.

, UIApplicationDelegate , , . applicationWillResignActive.

• didEnterBackground willResignActive, .

• willEnterForeground didBecomeActive, didBecomeActive (. ).

• willResignActive didEnterBackground, . 10% . , didBecomeActive, , .

• willTerminate iOS. iOS 2 3 iOS. , "" , . ( - , , - .)

:

• stopTasks/startTasks willResignActive didBecomeActive.
• / willResignActive/didBecomeActive didEnterBackground/willEnterForeground. , .