iOS Tracking CLCircularRegion - Heisenbug

我的一个iOS应用程序似乎具有经典Heisenbug的症状。应用程序跟踪用户的家庭位置，以便在用户进入和退出其家庭位置时发生某些事件。

当我测试应用程序时，它运行良好。我走进和走出一个CLCircularRegion，它对我尝试的每一种方式都有效。它在后台与应用程序一起工作。它适用于关闭的应用程序。它适用于前台的应用程序。它适用于绿色鸡蛋和火腿。

不幸的是，用户报告的问题将延迟 15 分钟左右。用户将进入他们的家，但事件要到以后才会发生。在某些情况下，该事件根本不会发生。模式似乎是当用户第一次开始使用该应用程序时，它工作得很好。大约一天后，该应用程序似乎也无法正常工作。事件被延迟。

我将是第一个承认我不是CLLocationManager和CLCircularRegion内部运作的专家。我相信我已经正确设置了所有内容，并且我很难弄清楚如何调试这样的东西。

无论如何，我将在这里展示我的一些代码。请记住，这是使用 Xamarin 开发的，因此它是在 C# 中。

AppDelegate.cs

public static AppDelegate self;
private CLLocationManager locationManager;
private CLCircularRegion[] locationFences;

private void initializeLocationManager()
{
    this.locationManager = new CLLocationManager();
    // iOS 8 additional permissions requirements
    if (UIDevice.CurrentDevice.CheckSystemVersion(8, 0))
    {
        locationManager.RequestAlwaysAuthorization();
    }
    locationManager.AuthorizationChanged += (sender, e) =>
    {
        var status = e.Status;
        // Location services was turned off or turned off for this specific application.
        if (status == CLAuthorizationStatus.Denied)
        {
            stopLocationUpdates();
        }
        else if (status == CLAuthorizationStatus.AuthorizedAlways &&
            iOSMethods.getKeyChainBool(OptionsViewController.GENERIC, OptionsViewController.SERVICE_GEOLOCATION_ENABLED))
        {
            startLocationUpdates();
        }
    };
    if (CLLocationManager.IsMonitoringAvailable(typeof(CLCircularRegion)))
    {
        locationManager.RegionEntered += (sender, e) =>
        {
            setRegionStatus(e, "Inside");
        };
        locationManager.RegionLeft += (sender, e) =>
        {
            setRegionStatus(e, "Outside");
        };
        locationManager.DidDetermineState += (sender, e) =>
        {
            setRegionStatus(e);
        };
    }
    else
    {
        // cant do it with this device
    }
    init();
}
public void init()
{
    var data = SQL.query<SQLTables.RoomLocationData>("SELECT * FROM RoomLocationData").ToArray();
    int dLen = data.Length;
    if (dLen > 0)
    {
        locationFences = new CLCircularRegion[dLen];
        for (int x = 0; x < dLen; x++)
        {
            var d = data[x];
            CLCircularRegion locationFence = new CLCircularRegion(new CLLocationCoordinate2D(d.Latitude, d.Longitude), d.Radius, d.SomeID.ToString() + ":" + d.AnotherID.ToString());
            locationFence.NotifyOnEntry = true;
            locationFence.NotifyOnExit = true;
            locationFences[x] = locationFence;
        }
    }
}
private void setRegionStatus(CLRegionEventArgs e, string status, bool calledFromDidDetermineState = false)
{
    string identifier = e.Region.Identifier;
    string lastStatus = iOSMethods.getKeyChainItem(OptionsViewController.GENERIC, OptionsViewController.SERVICE_LAST_GEO_STATUS);
    if (lastStatus == status + ":" + identifier)
    {
        return;
    }
    iOSMethods.setKeychainItem(OptionsViewController.GENERIC, OptionsViewController.SERVICE_LAST_GEO_STATUS, status + ":" + identifier);
    string[] split = identifier.Split(new string[] { ":" }, StringSplitOptions.RemoveEmptyEntries);
    if (split.Length == 2)
    {
        try
        {
            int someID = Convert.ToInt32(split[0]);
            int anotherID = Convert.ToInt32(split[1]);
            // Notifies our API of a change.
            updateGeofenceStatus(someID, anotherID, status);
            if (iOSMethods.getKeyChainBool(OptionsViewController.GENERIC, OptionsViewController.SERVICE_GEOLOCATION_NOTIFICATIONS) &&
                (status == "Inside" || status == "Outside" || status == "Unknown"))
            {
                var rm = SQL.query<SQLTables.KeyRoomPropertyData>("SELECT * FROM KeyRoomPropertyData WHERE SomeID ID = ? AND AnotherID = ?",
                    new object[] { someID, anotherID }).ToArray();
                if (rm.Length > 0)
                {
                    if (status == "Unknown")
                    {
                        return;
                    }
                    var rmD = rm[0];
                    UILocalNotification notification = new UILocalNotification();
                    notification.AlertAction = "Geolocation Event";
                    notification.AlertBody = status == "Inside" ? "Entered " + rmD.SomeName + ": " + rmD.AnotherName :
                        status == "Outside" ? "Exited " + rmD.SomeName + ": " + rmD.AnotherName :
                        "Geolocation update failed. If you would like to continue to use Geolocation, please make sure location services are enabled and are allowed for this application.";
                    notification.SoundName = UILocalNotification.DefaultSoundName;
                    notification.FireDate = NSDate.Now;
                    UIApplication.SharedApplication.ScheduleLocalNotification(notification);
                }
            }
        }
        catch (Exception er)
        {
            // conversion failed. we don't have ints for some reason.
        }
    }
}
private void setRegionStatus(CLRegionStateDeterminedEventArgs e)
{
    string state = "";
    if (e.State == CLRegionState.Inside)
    {
        state = "Inside";
    }
    else if (e.State == CLRegionState.Outside)
    {
        state = "Outside";
    }
    else
    {
        state = "Unknown";
    }
    CLRegionEventArgs ee = new CLRegionEventArgs(e.Region);
    setRegionStatus(ee, state, true);
}
public void startLocationUpdates()
{
    if (CLLocationManager.LocationServicesEnabled)
    {
        init();
        if (locationFences != null)
        {
            foreach (CLCircularRegion location in locationFences)
            {
                locationManager.StartMonitoring(location);
                Timer t = new Timer(new TimerCallback(delegate(object o) { locationManager.RequestState(location); }), null, TimeSpan.FromMilliseconds(500), TimeSpan.FromMilliseconds(-1));
            }
        }
    }
}
public void stopLocationUpdates(bool isRestarting = false)
{
    if (locationFences != null)
    {
        foreach (CLCircularRegion location in locationFences)
        {
            locationManager.StopMonitoring(location);
        }
    }
    if (!isRestarting)
    {
        var rooms = SQL.query<SQLTables.KeyRoomPropertyData>("SELECT * FROM KeyRoomPropertyData").ToArray();
        foreach (SQLTables.KeyRoomPropertyData room in rooms)
        {
            // notifies our API of a change
            updateGeofenceStatus(room.SomeID, room.AnotherID, "Unknown");
        }
    }
}

我知道任何人都可以筛选很多代码，但是在这一点上，我真的没有关于导致此错误的原因的良好理论，或者是否可以使用iOS的限制进行修复。

我有一些理论是如果CLLocationManager.PausesLocationUpdatesAutomatically财产可能与它有关，或者与CLLocationManager的其他一些属性有关，例如ActivityType、DesiredAccuracy或DistanceFilter。我已经将所有这些保留为默认值，我认为这很好，但我不确定。

另一种理论是，在"服务"在后台运行一段时间后，会抛出一个未捕获的异常。如果是这种情况，iOS 会做些什么来给我堆栈跟踪或其他东西吗？在我的所有测试中，我从未遇到过此代码引发的任何异常，所以我有点怀疑这是问题所在。不过，在这一点上，我愿意接受任何想法或建议。

另外，请记住，为了使此应用程序按预期方式工作，位置更新事件必须在用户输入或存在CLCircularRegion后立即发生(至少在一分钟左右(。显然，我必须将其留给用户以保持其位置服务启用并允许应用程序具有适当的权限。