每隔N分钟在后台迅速将位置发送到服务器

Question

i want to sent the location to the server when the app is background, i tried with many way but can't get the solution

I tried with the timer function using the timer and using function

        self.bgtimer = Timer.scheduledTimer(timeInterval:60, target: self, selector: #selector(AppDelegate.bgtimer(_:)), userInfo: nil, repeats: true)
        RunLoop.current.add(self.bgtimer, forMode: RunLoopMode.defaultRunLoopMode)
        RunLoop.current.run()

but i when i stop the timer when the app becomes active

     if UIApplication.shared.applicationState == .active {
         RunLoop.current.cancelPerformSelectors(withTarget: self.bgtimer)
        timer.invalidate()

    }

but the app not function properly collection view and back function everything is not working properly

Answer 1

In DidBackground:

1. stop normalTimer.
2. start New backgroundTaskTimer

In WillForeground:

1. stop backgroundTaskTimer.
2. start normalTimer

Find below sample code:

In Appdelegate:

Declaration:

  var backgroundUpdateTask: UIBackgroundTaskIdentifier!

  var backgroundTaskTimer:Timer! = Timer()

Implementation:

func doBackgroundTask() {
    DispatchQueue.global(qos: .default).async {
        self.beginBackgroundTask()

        if self.backgroundTaskTimer != nil {
            self.backgroundTaskTimer.invalidate()
            self.backgroundTaskTimer = nil
        }

        //Making the app to run in background forever by calling the API
        self.backgroundTaskTimer = Timer.scheduledTimer(timeInterval: 10, target: self, selector: #selector(self.startTracking), userInfo: nil, repeats: true)
        RunLoop.current.add(self.backgroundTaskTimer, forMode: RunLoopMode.defaultRunLoopMode)
        RunLoop.current.run()

        // End the background task.
        self.endBackgroundTask()

    }
}

func beginBackgroundTask() {
    self.backgroundUpdateTask = UIApplication.shared.beginBackgroundTask(withName: "Track trip", expirationHandler: {
        self.endBackgroundTask()
    })
}

func endBackgroundTask() {
    UIApplication.shared.endBackgroundTask(self.backgroundUpdateTask)
    self.backgroundUpdateTask = UIBackgroundTaskInvalid
}

In ApplicationDidEnterBackground:

 func applicationDidEnterBackground(_ application: UIApplication) {

    //Start the background fetch
     self.doBackgroundTask()
 }

In ApplicationWillEnterForeground:

func applicationWillEnterForeground(_ application: UIApplication) {

    if self.backgroundTaskTimer != nil {
        self.backgroundTaskTimer.invalidate()
        self.backgroundTaskTimer = nil
    }
}