我是 Swift 的新手，我尝试使用这个

How to set accuracy and distance filter when using MKMapView

不知道为什么这段代码不起作用:

//start  mehtod out of scope
lazy var locationManager: CLLocationManager! = {
    let locationManager = CLLocationManager()


    //configeration for  user location access
    //The delegate object to receive update events.
    locationManager.delegate = self
    //The receiver does its best to achieve the requested accuracy
    //locationManager.desiredAccuracy = kCLLocationAccuracyBest
     self.locationManager.distanceFilter = 10.0
    //Requests permission to use location services while the app is in the foreground
    locationManager.requestWhenInUseAuthorization()
    //allow update notification when apps stay on background
    locationManager.allowsBackgroundLocationUpdates = true

    return locationManager
}() 

当我设置时它工作正常:

locationManager.desiredAccuracy = kCLLocationAccuracyBest

那么我想要什么:

如果用户改变她的定位然后连续 15 分钟调用一个方法，我想在每 250 米后获得 LAT 和 LONG

 pushLocation(lat:double,long:double)

最佳答案

这是我正在使用的代码 - 全部在 Swift 3.0 中。

locationManager 的这个设置将负责您所追求的距离过滤和准确性:

lazy var locationManager: CLLocationManager = {
    [unowned self] in
    var _locationManager = CLLocationManager()
    _locationManager.delegate = self
    _locationManager.desiredAccuracy = [Your Value For trackingAccuracy - see below]
    _locationManager.distanceFilter = [Your Value For the filter i.e., 250 for 250 meters]
    _locationManager.allowsBackgroundLocationUpdates = true
    _locationManager.pausesLocationUpdatesAutomatically = false 
    _locationManager.activityType = .fitness
    return _locationManager
    }()

精度设置将来自位置管理器中的预定义设置，例如 kCLLocationAccuracyNearestTenMeters 或 kCLLocationAccuracyHundredMeters。

即使您的应用不在前台，允许后台更新的选项也能让您获得新的积分。如果手机会不时停止移动，则有必要自动关闭暂停 - 否则，如果您的用户停止休息 5 分钟并且不会重新打开它，它将自动关闭捕获 - 您必须在您重新设置这些完成了。

授权状态应在单独的检查中处理，如下所示，以便您可以在尚未获得授权时请求授权:

    if CLLocationManager.authorizationStatus() != .authorizedAlways     // Check authorization for location tracking
    {
        locationManager.requestAlwaysAuthorization()                    // Will callbackdidChange... once user responds
    } else {
        locationManager.startUpdatingLocation()
    }

由于获得授权有延迟，如果您必须发出请求，您需要等待请求它开始更新位置，直到您收到 locationManager 的回复，您可以按以下方式执行:

@nonobjc func locationManager(manager: CLLocationManager!, didChangeAuthorizationStatus status: CLAuthorizationStatus) {
    switch status
    {
    case .authorizedAlways:
        locationManager.startUpdatingLocation()

    default:
        [Whatever you want to do - you can't get locations]
    }
}

我需要 .authorizedAlways，根据您的用例，您可以不用 .authorizedWhenInUse。

我根据检查 locationManager 传回给我的位置中的精度字段，添加了一个额外的精度过滤器。请注意，有单独的水平和垂直精度值(以米为单位的置信距离)；如果您想使用海拔值，您需要注意第二个精度值，因为海拔在 iPhone 中本来就不那么准确。

我还检查新点是否是在前一个点之后捕获的 - 有时会出现乱序值并指示“有问题”的值。我读到您可能会得到小于 0 的准确度值以表明存在问题，因此您可能需要在使用该职位之前检查一下，但我还没有看到该问题。这是代码:

// Called back by location manager - passes arrays of new CLLocation points captured. With distanceFilter set to 250, this will get called for a change of 250M.  You'll want to save the value for your timed pushLocation function.

// This function needs to be trim as it continues to be called when TrailHead is in the background and, if 
// we take too long we'll get killed by iOS.

var savePosition: CLLocationCoordinate2D?
private var latestTimeProcessed = Date()  // Initialize to ensure any point accepted received after initialization

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation])
{
    for location in locations {
        if latestTimeProcessed.compare(location.timeStamp) == .orderedAscending        // Out of seq indicates a locationManager problem - discard
            && location.horizontalAccuracy < [Whatever accuracy limit you want to use]    // Applying a user-selected quality filter
        {
            latestTimeProcessed = location.timeStamp      // Used to discard any earlier timestamped points returned by the location manager
            [PROCESS THE POSITION HERE - E.G.]

            savePosition = locations.last

        }
    }
}

就推送更新而言，我会添加一个计时器

private var myTimer: Timer? = nil  
private var longInterval = 900.0     // 900 seconds = 15 minutes

override func viewDidLoad()
{
    ....
        myTimer = Timer(timeInterval: timerInterval, target: myself, selector: #selector(myself.pushLocation), userInfo: nil, repeats: true)
        RunLoop.current.add(myTimer!, forMode: RunLoopMode.commonModes)
    ....
}

pushLocation(lat:double,long:double){
    [Use savePosition.latitude, savePosition.longitude]
}

希望这有助于...

关于ios - 如何设置自定义距离 Filter ，在 Swift 中是否可行？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41043936/