我已经做了几个月的 iOS 开发，最近我正在开发一个公交应用程序。 我目前正在模仿公共(public)汽车的运动，并在公共(public)汽车站上设置多个注释。出于测试目的，我只设置了一个公交车站，并试图监控公交车何时进入和离开该区域。

奇怪的是，我的 didStartMonitoringForRegion 方法被完美地调用了，但是 didEnterRegion 和 didExitRegion 方法都没有被调用。每次我运行该程序时，公交车几乎都会在没有提示我的情况下经过车站。

有人可以向我解释为什么会发生这种情况以及如何解决吗？

let locationManager = CLLocationManager()
var allBusAnnotations = [MKPointAnnotation]()
var summitEastBusStations = [CLLocationCoordinate2D]()
var busStopNames = ["Dix Stadium", "Risman Plaza", "Terrace Drive", "Terrace Drive 2","C-Midway","Theatre Dr.","East Main Street","South Lincoln"]
var radius = 500 as CLLocationDistance

// 0.02 is the best zoom in factor
var mapZoomInFactor : Double = 0.02

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    self.getBusStop()
    self.locationManager.delegate = self
    // gets the exact location of the user
    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest
    // gets the user's location only when the app is in use and not background
    self.locationManager.requestWhenInUseAuthorization()
    self.locationManager.startUpdatingLocation()

    self.mapView.showsUserLocation = true
    self.setBusStopAnnotations(summitEastBusStations)
    // self.mapView.mapType = MKMapType.Satellite  
}
    func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {

    // sends the latitude and longitude to the Apple Servers then returns the address
    CLGeocoder().reverseGeocodeLocation(manager.location, completionHandler: { (placeMarks: [AnyObject]!, error: NSError!) -> Void in

        if error != nil
        {
            println("Reverse Geocode Failed: " + error.localizedDescription)
            return
        }

        if placeMarks.count > 0
        {
            // gets the most updated location
            let pm = placeMarks.last as! CLPlacemark

            let centre = CLLocationCoordinate2D(latitude: manager.location.coordinate.latitude, longitude: manager.location.coordinate.longitude)

            // draws a circle in which the map will zoom to
            let region = MKCoordinateRegion(center: centre, span: MKCoordinateSpan(latitudeDelta: self.mapZoomInFactor, longitudeDelta: self.mapZoomInFactor))

            self.mapView.setRegion(region, animated: true)

            self.displayLocationInfo(pm)

            // self.distanceToClosestAnnotation(pm)

            self.geoFencing()

            // YOU CAN IGNORE THIS WHOLE PART. IT'S IRRELEVANT FOR THIS QUESTION
            var repeatTimes = 0
            var count = 0 
            while(count <= 7)
            {
                if count == (self.summitEastBusStations.count - 1)
                {
                    count = 1
                    ++repeatTimes
                }
                else if repeatTimes == 1
                {
                    count = 0
                    ++repeatTimes
                }
                else if repeatTimes == 2
                {
                    break
                }

                self.distanceToBusStop(pm, count: count)
                ++count
            }
        }
    })
}
    func locationManager(manager: CLLocationManager!, didFailWithError error: NSError!) {
    println("Location Manager Failed: " + error.localizedDescription)
}

func locationManager(manager: CLLocationManager!, didStartMonitoringForRegion region: CLRegion!) {
    println("The region is monitored")
    println("The monitored region is \(region.description)")
}

func locationManager(manager: CLLocationManager!, monitoringDidFailForRegion region: CLRegion!, withError error: NSError!) {
    println("Failed to monitor the stated region")
}

func locationManager(manager: CLLocationManager!, didEnterRegion region: CLRegion!) {
    println("The bus has entered the region")
}

func locationManager(manager: CLLocationManager!, didExitRegion region: CLRegion!) {
    println("The bus has left the region")
}
func geoFencing()
{

    let rismanPlaza = CLLocationCoordinate2D(latitude: 41.1469492, longitude: -81.344068)

    var currentBusStop = CLLocation(latitude: rismanPlaza.latitude, longitude: rismanPlaza.longitude)
    addRadiusCircle(currentBusStop)

    let busStopRegion = CLCircularRegion(center: CLLocationCoordinate2D(latitude: rismanPlaza.latitude, longitude: rismanPlaza.longitude), radius: radius, identifier: busStopNames[1])

    if radius > self.locationManager.maximumRegionMonitoringDistance
    {
        radius = self.locationManager.maximumRegionMonitoringDistance
    }

    locationManager.startMonitoringForRegion(busStopRegion)

}

// creates the radius around the specified location
func addRadiusCircle(location: CLLocation)
{
    self.mapView.delegate = self
    var circle = MKCircle(centerCoordinate: location.coordinate, radius: radius)
    self.mapView.addOverlay(circle)
}

// performs the actual circle colouring
func mapView(mapView: MKMapView!, rendererForOverlay overlay: MKOverlay!) -> MKOverlayRenderer!
{
    if overlay is MKCircle
    {
        var circle = MKCircleRenderer(overlay: overlay)
        circle.strokeColor = UIColor.redColor()
        circle.fillColor = UIColor(red: 255, green: 0, blue: 0, alpha: 0.1)
        circle.lineWidth = 1
        return circle
    }
    else
    {
        return nil
    }
}

最佳答案

我最终改用了 CLRegion.containsCoordinate(location.coordinate) 方法。它的工作方式几乎相同。

一旦对象进入我设置的区域，它就会返回 true，从这里我可以知道它何时进入和离开该区域。

关于iOS 区域监控不起作用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/32548000/