MapKit缩放按钮[重复]

Question

我的问题是关于地图服务我正在使用带有自定义切片服务的地图现在我需要添加两个按钮或一个步进器来放大和缩小，并且我正在使用 MapKit 库。有人可以帮忙吗？

Answer 1

查看答案

switch sender.tag {
    case 10:
    //Zoom In

        var region: MKCoordinateRegion = map_view.region
        region.span.latitudeDelta /= 2.0
        region.span.longitudeDelta /= 2.0
        map_view.setRegion(region, animated: true)
    case 20:

   //Zoom Out
        var region: MKCoordinateRegion = map_view.region
        region.span.latitudeDelta = min(region.span.latitudeDelta * 2.0, 180.0)
        region.span.longitudeDelta = min(region.span.longitudeDelta * 2.0, 180.0)
        map_view.setRegion(region, animated: true)
}

Answer 2

这是 swift 3 中的答案

放大

let region = MKCoordinateRegionMake(self.mapView.region.center, MKCoordinateSpanMake(mapView.region.span.latitudeDelta*0.7, mapView.region.span.longitudeDelta*0.7))
mapView.setRegion(region, animated: true)

用于缩小

   let zoom = getZoom() // to get the value of zoom of your map.
   if zoom > 3.5{ // **here i have used the condition that avoid the mapview to zoom less then 3.5 to avoid crash.**

            let region = MKCoordinateRegionMake(self.mapView.region.center, MKCoordinateSpanMake(mapView.region.span.latitudeDelta/0.7, mapView.region.span.longitudeDelta/0.7))
            mapView.setRegion(region, animated: true)
        }

在这里您可以获取地图视图的缩放程度。

func getZoom() -> Double {

    var angleCamera = self.mapView.camera.heading
    if angleCamera > 270 {
        angleCamera = 360 - angleCamera
    } else if angleCamera > 90 {
        angleCamera = fabs(angleCamera - 180)
    }
    let angleRad = Double.pi * angleCamera / 180
    let width = Double(self.view.frame.size.width)
    let height = Double(self.view.frame.size.height)
    let heightOffset : Double = 20
    let spanStraight = width * self.mapView.region.span.longitudeDelta / (width * cos(angleRad) + (height - heightOffset) * sin(angleRad))
    return log2(360 * ((width / 256) / spanStraight)) + 1;
}

它对我有用。