Question

我在这是怎么回事，而他们的工作，即使应用程序被关闭跟踪用户Xamarin项目。基本上，这是一个为我们的客户（我们有ERP）的应用程序，用于跟踪他们的卖家。

为此，我实现了一个非常简单的BroadcastReceiver来启动服务（LocationService），该服务将获取用户的位置并将其保存在数据库中或将其发布到某些API中。

的问题是，当我不使用的LocationManager，它工作正常（I关闭该应用程序，并将其保持烘烤消息例如）。但是，如果我使用LocationManager，则应用程序关闭后服务会“崩溃”并停止跟踪。难道我做错了什么？该项目是完全配置用于GPS跟踪（正常工作时的应用程序是打开或悬浮）。

PS：这是我第一次使用Xamarin.Android。之前，我刚刚与Xamarin.Forms工作。

这里是LogCat。触发AlarmManager并尝试获取位置时似乎会发生这种情况。

这是我的代码：

开始跟踪

private void StartTrackingAlarm(int period)
    {
        Intent intent = new Intent(this, typeof(TrackingService));
        PendingIntent pendingIntent = PendingIntent.GetBroadcast(this, 0, intent, PendingIntentFlags.CancelCurrent);

        WriteLine($"Started tracking with period of {period} seconds.");
        AlarmManager manager = (AlarmManager)GetSystemService(AlarmService);
        manager.SetRepeating(AlarmType.RtcWakeup, SystemClock.ElapsedRealtime(), period * 1000, pendingIntent);
    }

    private void StopTrackingAlarm()
    {
        Intent intent = new Intent(this, typeof(TrackingService));
        PendingIntent pendingIntent = PendingIntent.GetBroadcast(this, 0, intent, 0);

        WriteLine($"Stopped tracking at {DateTime.Now.ToLongTimeString()} seconds.");
        AlarmManager manager = (AlarmManager)GetSystemService(AlarmService);
        manager.Cancel(pendingIntent);
    }

广播接收器

[BroadcastReceiver(Enabled = true)]
[IntentFilter(new string[] { "android.intent.action.BOOT_COMPLETED" }, Priority = (int)IntentFilterPriority.HighPriority)]
public class TrackingService : BroadcastReceiver
{
    public override void OnReceive(Context context, Intent intent)
    {
        Intent intentToStart = new Intent(context, typeof(LocationService));
        context.StartService(intentToStart);
    }
}

LocationService

[Service]
public class LocationService : IntentService, ILocationListener
{
    private string LogTag => $"[{nameof(LocationService)}]";
    private LocationManager LocManager { get; set; }
    private string LocationProvider { get; set; }

    protected override void OnHandleIntent(Intent intent)
    {
        Log.WriteLine(LogPriority.Debug, LogTag, $"Handling intent at {DateTime.Now.ToLongTimeString()}");
        InitializeLocationManager();

        if (LocManager.IsProviderEnabled(LocationProvider))
        {
            LocManager.RequestSingleUpdate(LocationProvider, this, null);
            Location location = LocManager.GetLastKnownLocation(LocationProvider);
            Log.WriteLine(LogPriority.Debug, LogTag, $"Last Position: [{location.Latitude}, {location.Longitude}].");
        }      
    }

    private void InitializeLocationManager()
    {
        LocManager = (LocationManager)GetSystemService(LocationService);
        Criteria criteriaForLocationService = new Criteria { Accuracy = Accuracy.Fine };
        IList<string> acceptableLocationProviders = LocManager.GetProviders(criteriaForLocationService, true);

        if (acceptableLocationProviders.Any())            
            LocationProvider = acceptableLocationProviders.First();            
        else            
            LocationProvider = string.Empty;

        Log.Debug(LogTag, $"Using {LocationProvider} at {DateTime.Now}.");
    }

    #region ILocationListener
    public void OnLocationChanged(Location location) { }

    public void OnProviderDisabled(string provider) { }

    public void OnProviderEnabled(string provider) { }

    public void OnStatusChanged(string provider, [GeneratedEnum] Availability status, Bundle extras) { }
    #endregion
}

应用关闭时的AlarmManager完成服务（LocationManager）

0 个答案: