Question

我有一张地图，上面有一个自定义的UIView。我正在根据缩放级别计算圆的半径。

func getCenterCoordinate() -> CLLocationCoordinate2D {
    let centerPoint = self.mapView.center
    let centerCoordinate = self.mapView.projection.coordinate(for: centerPoint)
    return centerCoordinate
}

func getTopCenterCoordinate() -> CLLocationCoordinate2D {
    // to get coordinate from CGPoint of your map
    let topCenterCoor = self.mapView.convert(CGPoint(x:self.circleView.frame.size.width / 2.0, y:0), from: self.circleView)
    let point = self.mapView.projection.coordinate(for: topCenterCoor)
    return point
}

func getRadius() -> CLLocationDistance {

    let centerCoordinate = getCenterCoordinate()
    // init center location from center coordinate
    let centerLocation = CLLocation(latitude: centerCoordinate.latitude, longitude: centerCoordinate.longitude)
    let topCenterCoordinate = self.getTopCenterCoordinate()
    let topCenterLocation = CLLocation(latitude: topCenterCoordinate.latitude, longitude: topCenterCoordinate.longitude)

    let radius = CLLocationDistance(centerLocation.distance(from: topCenterLocation)) / 1000
    print(radius)
    return round(radius)
}

现在，我想根据给定的半径缩放地图？我怎么能这样做？

Answer 1

您可以在班级中创建扩展名： -

extension GMSCircle {

    func bounds() -> GMSCoordinateBounds {

        func locationMinMax(positive : Bool) -> CLLocationCoordinate2D {

            let sign:Double = positive ? 1 : -1
            let dx  = sign * self.radius  / 6378000 * (180/Double.pi)
            let lat = position.latitude + dx
            let lon = position.longitude + dx / cos(position.latitude * .pi/180)

            return CLLocationCoordinate2D(latitude: lat, longitude: lon)
        }

        return GMSCoordinateBounds(coordinate: locationMinMax(positive: true), 
                                   coordinate: locationMinMax(positive: false))
    }

}

本地变量

var cirlce: GMSCircle!
var circleCenter = CLLocationCoordinate2D()

现在你可以使用这个绑定到你的圆圈缩放。

@IBAction func circleZoom(_ sender: Any) {

    // Now Map Zoom with Circle size.
    let update = GMSCameraUpdate.fit(cirlce.bounds())
    self.googleMaps.animate(with: update)
}

func mapView(_ mapView: GMSMapView, markerInfoWindow marker: GMSMarker) -> UIView? {

    let customInfoWindow = Bundle.main.loadNibNamed("Subview", 
                                                    owner: self, 
                                                    options: nil)?[0] as! CustomInfoWindow

    customInfoWindow.title.text = marker.title!
    customInfoWindow.button.tag = 0
    customInfoWindow.button.addTarget(self, 
                                      action: #selector(YourViewController.buttonpush(sender:)), 
                                      for: .touchUpInside)

    return customInfoWindow
}

// Location Manager
func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {

    let location = locations.last
    let camera = GMSCameraPosition.camera(withLatitude: (location?.coordinate.latitude)!, 
                                          longitude: (location?.coordinate.longitude)!, 
                                          zoom: zoom)

    self.googleMaps?.animate(to: camera)
    self.locationManager.stopUpdatingLocation() 
}

当然，它会帮助你。我在地图上使用滑块。样本屏幕截图。第一次放大和第二次缩小。

Here您可以在Swift和Objective C中找到关于圆形创建和地图缩放的更多详细信息

Answer 2

选择圆周边的任何坐标，并将地图的缩放或相机缩放设置为该坐标的边界，添加一些填充的路径。现在，对于这种逻辑，如果您的地图已启用用户缩放，则每次地图相机移动或重新定位时，您都必须重新计算。

您可以使用此方法执行此操作：bool TreeItem::setData(int column, const QVariant &value) { if (column < 0 || column >= itemData.size()) return false; itemData[column] = value; return true; }

这里的边界是mapView.animateWithCameraUpdate(GMSCameraUpdate.fitBounds(bounds, withPadding: 50.0))对象。

希望这有帮助

谷歌地图半径缩放级别

2 个答案: