ios - 如何过滤无效位置更新 iOS

Question

我使用 CCLocationManager 每 1 分钟跟踪一次位置，这是我的 didUpdateLocation 委托(delegate)方法:

func changeLocationAccuracy() {
    switch locationManager.desiredAccuracy {
    case kCLLocationAccuracyBest:
        locationManager.desiredAccuracy = kCLLocationAccuracyThreeKilometers
        locationManager.distanceFilter = 99999
    case kCLLocationAccuracyThreeKilometers:
        locationManager.desiredAccuracy = kCLLocationAccuracyBest
        locationManager.distanceFilter = kCLDistanceFilterNone
    default: break
    }
}

func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    guard let newLocation = locations.last else {
        return
    }

    let interval = newLocation.timestamp.timeIntervalSinceNow

    if abs(interval) > 5 || locationManager.desiredAccuracy != kCLLocationAccuracyBest {
        return
    }

    if newLocation.horizontalAccuracy < 0 {
        return
    }

    if currentLocation != nil && newLocation.timestamp.timeIntervalSince(currentLocation.timestamp) < 0 {
        return
    }

    currentLocation = newLocation

    print("interval: \(interval)")
    print("desiredAccuracy: \(locationManager.desiredAccuracy)")
    print("accuracy: \(newLocation.horizontalAccuracy)")

    timer = Timer.scheduledTimer(timeInterval: 60, target: self, selector: #selector(LocationService.changeLocationAccuracy), userInfo: nil, repeats: false)
    changeLocationAccuracy()
}

正如您在上面看到的，我正在过滤掉无效的位置，但问题是我的距离在不移动手机的情况下发生变化。这是我的日志数据:

interval: -0.0140599608421326
desiredAccuracy: -1.0
accuracy: 90.8123422472749
distance : 113.473282606026
-----------
interval: -0.0128610134124756
desiredAccuracy: -1.0
accuracy: 90.8123422472749
distance : 113.473282606026
-----------
interval: -0.00315600633621216
desiredAccuracy: -1.0
accuracy: 2000.0
distance : 180.768761850842
-----------
interval: -0.00381100177764893
desiredAccuracy: -1.0
accuracy: 2000.0
distance : 180.768761850842
-----------
interval: -0.0131250023841858
desiredAccuracy: -1.0
accuracy: 219.000225316427
distance : 0.763731059143118
-----------
interval: -0.0137189626693726
desiredAccuracy: -1.0
accuracy: 219.000225316427
distance : 0.763731059143118

有什么解决办法吗？提前致谢。

Answer 1

您可能只是期望比实际提供的更准确。首先，手机最初使用 GPS 以外的其他机载传感器。其次，GPS 系统本身并不是特别准确。因此，即使您是静止的，随着时间的推移，手机认为您所在的位置可能会发生微小变化，这既是因为不同的传感器预热，也仅仅是因为最准确的传感器 GPS 并不是那么准确。