当我得到位置时,如何进行后台网络呼叫?

如果应用程序处于后台状态,则获取 UIBackgroundTaskIdentifier

 func scheduledLocationManager(_ manager: APScheduledLocationManager, didUpdateLocations locations: [CLLocation]) {

    print(locations.last?.description ?? "no location")

    // Get the background identifier if the app is in background mode
    if UIApplication.shared.applicationState == .background {
       backgroundUpdateTask = UIApplication.shared.beginBackgroundTask { [weak self] in
            if let strongSelf = self {
                UIApplication.shared.endBackgroundTask(strongSelf.backgroundUpdateTask)
                self.backgroundUpdateTask = UIBackgroundTaskInvalid
            }
        }
    }

    // Call the api to update the location to your server
    Alamofire.request("https://testomkar.herokuapp.com/log", method: .post, parameters: ["log":locations.last?.description ?? "no location"]).validate().responseJSON(completionHandler: { (responce) in

           //API completion block invalidate the identifier if it is not invalid already.
           if self.backgroundUpdateTask != nil && self.backgroundUpdateTask != UIBackgroundTaskInvalid {
                 UIApplication.shared.endBackgroundTask(backgroundUpdateTask)
                 self.backgroundUpdateTask = UIBackgroundTaskInvalid
           }
     })
}