【发布时间】：2020-12-03 11:09:42
【问题描述】：
我在后台使用地理定位跟踪，当应用程序在后台运行几分钟后，对 locationManager.stopUpdateLocations () 的调用停止工作 - 顶部的蓝条没有被移除，应用程序继续使用地理定位服务.如果您调用 locationManager.stopUpdateLocations() 而不将应用程序最小化到后台，则服务将关闭并且顶部的蓝条消失。任何遇到过这种情况的人，请帮忙，已经花了几天时间 - 都无济于事。禁用所有逻辑，剩下的就是：启动地理定位服务（locationManager.startUpdateLocations）并尝试停止（locationManager.stopUpdateLocations）。根本没有计时器或任何其他逻辑。
import CoreLocation
final class MyLocationService: NSObject, CLLocationManagerDelegate {
private let locationManager = CLLocationManager()
func sendCoord() {
print("Send you coordinates")
}
func requestPermission() {
locationManager.requestWhenInUseAuthorization()
}
func start() {
locationManager.delegate = self
locationManager.pausesLocationUpdatesAutomatically = false
locationManager.allowsBackgroundLocationUpdates = true
locationManager.desiredAccuracy = kCLLocationAccuracyHundredMeters
locationManager.distanceFilter = 300
locationManager.startUpdatingLocation()
sendCoord()
}
func stop() {
locationManager.pausesLocationUpdatesAutomatically = true
locationManager.stopUpdatingLocation()
locationManager.allowsBackgroundLocationUpdates = false
locationManager.delegate = nil
}
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
sendCoord()
}
}
这是我的 ViewController 类：
import UIKit
import Foundation
import CoreLocation
class ViewController: UIViewController {
// *** Internal variables *** //
private let locationService = MyLocationService()
var needPermissionForLocationServices = false
@IBOutlet weak var toolBar: UIToolbar!
@IBOutlet weak var startLocationToolBarButton: UIBarButtonItem!
@IBAction func startLocationToolBarButtonAction(_ sender: UIBarButtonItem) {
if CLLocationManager.locationServicesEnabled() {
switch(CLLocationManager.authorizationStatus()) {
case .notDetermined, .restricted, .denied:
DispatchQueue.main.async(execute: {
let alert = UIAlertController(title: "Error!", message: "Location services is off", preferredStyle: UIAlertController.Style.alert)
alert.addAction(UIAlertAction(title: "Go to settings?", style: UIAlertAction.Style.default, handler: { (alert: UIAlertAction!) in
print("")
UIApplication.shared.open(NSURL(string:UIApplication.openSettingsURLString)! as URL)
}))
self.present(alert, animated: true, completion: nil)
})
case .authorizedAlways, .authorizedWhenInUse:
locationService.start()
}
} else {
DispatchQueue.main.async(execute: {
let alert = UIAlertController(title: "Error!", message: "Location services is off", preferredStyle: UIAlertController.Style.alert)
alert.addAction(UIAlertAction(title: "Go to settings?", style: UIAlertAction.Style.default, handler: { (alert: UIAlertAction!) in
print("")
UIApplication.shared.open(NSURL(string:UIApplication.openSettingsURLString)! as URL)
}))
self.present(alert, animated: true, completion: nil)
})
locationService.requestPermission()
}
}
@IBOutlet weak var stopLocationToolBarButton: UIBarButtonItem!
@IBAction func stopLocationToolBarButtonAction(_ sender: UIBarButtonItem) {
locationService.stop()
}
// *** View Controller Functions *** //
deinit {
print("Deinit: VC NO MEMORY LEAKS")
}
override func viewDidLoad() {
super.viewDidLoad()
locationService.requestPermission()
}
override func viewDidDisappear(_ animated: Bool) {
}
override func viewWillAppear(_ animated: Bool) {
view.backgroundColor = UIColor.white
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
【问题讨论】：
-
请在上下文中显示代码。您的目标应该是制作一个我们可以用来重现问题的实际工作项目。我们不仅需要一些代码摘录；我们需要查看代码在视图控制器中的确切位置，以及应该触发它的内容。
-
好的，修改文本
-
什么时候打电话给
stop？当您的应用在后台时，调用stop函数的代码似乎没有执行。 -
我通过点击 viewController 内的按钮来调用 stop，所以应用程序此时肯定处于活动状态并且处于前台