mbt3.swift

import UIKit
import BackgroundTasks

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        
        BGTaskScheduler.shared.register(
            forTaskWithIdentifier: "pl.snowdog.example.train",
            using: DispatchQueue.global()
        ) { task in
            self.handleMLTrain(task)
        }
        return true
    }

    private func scheduleMLTrain() {
        do {
            let request = BGProcessingTaskRequest(identifier: "pl.snowdog.example.train")
            request.requiresExternalPower = true
            request.requiresNetworkConnectivity = true
            try BGTaskScheduler.shared.submit(request)
        } catch {
            print(error)
        }
    }
}