查看用户是否在某个位置附近？斯威夫特4

Question

我希望能够看到用户是否位于Swift 4中另一个位置的5公里半径范围内。

例如：

User Location: 37.785834, -122.406417
Other Location: -117.564011, 48.302353

感谢任何帮助的人！

Answer 1

您可以使用Region Monitoring提供的CLLocationManager功能检测用户何时自动进入或离开地理区域。

开始监控指定坐标周围的圆形区域：

let center = CLLocationCoordinate2D(latitude: 37.785834, longitude: -122.406417)
// Make sure the app is authorized.
if CLLocationManager.authorizationStatus() == .authorizedAlways {
    // Make sure region monitoring is supported.
    if CLLocationManager.isMonitoringAvailable(for: CLCircularRegion.self) {
        // Register the region.
        let maxDistance = locationManager.maximumRegionMonitoringDistance
        let region = CLCircularRegion(center: center, 
             radius: 5000.0, identifier: "YourRegionID")
        region.notifyOnEntry = true
        region.notifyOnExit = false

        locationManager.startMonitoring(for: region)
    }
}

通过从CLLocationManagerDelegate实施合适的方法处理与区域相关的通知（在此示例中输入通知）：

func locationManager(_ manager: CLLocationManager, didEnterRegion region: CLRegion) {
    if let region = region as? CLCircularRegion {
        // your logic to handle region-entered notification
    }
}