ios – 如何在MKMapView中将引脚和贴图保持在移动叠加层的中心

如何在地图上垂直移动(通过Pan Gesture)另一个视图,使得引脚保持在覆盖图上方(而不是实际的MapKit覆盖图),如何将引脚置于地图中心.

请参阅附加屏幕截图,了解第一个和最终状态.

当用户平移上/下时,我已经获得了叠加层和屏幕顶部之间空间的CGRect.然而,当用户向上平移时,我如何使用它来移动地图和图钉同时放大地图……当用户向下平移时再次缩小,到目前为止我已经躲过了.

我尝试过不同的方法,从尝试调整可见矩形到调整地图视图的框架.答案可能在于一些MKMapRect / Region技巧.

(Freepik CC BY 3.0手形图标)

解决方法

实际上,keithbhunter的代码很慢,因为除了更快地更新区域之外,地图也会改变高度,这会导致额外的开销！

我更新了代码,使其顺利运行.

使用此代码,我所做的是保持地图视图的大小相同,但我移动中心点以补偿滑动视图的高度.

要使此代码生效,您必须修改keithbhunter的设置,以便mapView的底部约束完全固定到superview的底部(而不是pullView(以便mapView始终与超级视图的大小相同).设置是一样的.

此外,还可以使用变量maxMetersdistance自定义缩放量

在这里,我总是以埃菲尔铁塔为中心

import UIKit
import MapKit

class ViewController: UIViewController {

    @IBOutlet weak var mapView: MKMapView!
    @IBOutlet weak var slidingView: UIView!
    @IBOutlet weak var slidingViewHeight: NSLayoutConstraint!
    var maxMetersdistance:CGFloat = 10000.0; // customize this to set how far the map zooms out of the interest area

    override func viewDidLoad() {
        super.viewDidLoad()
        let pan = UIPanGestureRecognizer(target: self,action: "viewDidPan:")
        self.slidingView.addGestureRecognizer(pan)
        firstTimeCenter()
    }

    func firstTimeCenter(){
         var coordinate = CLLocationCoordinate2D(latitude: 48.8582,longitude: 2.2945)
        let region = MKCoordinateRegionMakeWithdistance(coordinate,Double(maxMetersdistance),Double(maxMetersdistance))
        self.mapView.setRegion(region,animated: true)
    }

    func reloadMap() {
        let height = CGFloat(self.slidingViewHeight.constant)
        var regiondistance = (maxMetersdistance / self.view.frame.height) * height
        regiondistance = maxMetersdistance - regiondistance
        var coordinate = CLLocationCoordinate2D(latitude: 48.8582,longitude: 2.2945)
        var mapRect = mapView.visibleMapRect;
        var metersPerMapPoint = MKMetersPerMapPointAtLatitude(coordinate.latitude);
        var metersPerPixel = CGFloat(metersPerMapPoint) * CGFloat(mapRect.size.width) / CGFloat(mapView.bounds.size.width);
        var totalMeters = Double(metersPerPixel) * Double(height/2)

        coordinate = self.translateCoord(coordinate,MetersLat: -totalMeters,MetersLong: 0.0)

        let region = MKCoordinateRegionMakeWithdistance(coordinate,Double(regiondistance),Double(regiondistance))
        self.mapView.setRegion(region,animated: false)
    }

    func viewDidPan(panGesture: UIPanGestureRecognizer) {
        let location = panGesture.locationInView(self.view)
        self.slidingViewHeight.constant = self.view.frame.size.height - location.y
        self.reloadMap()
    }

    func translateCoord(coord:CLLocationCoordinate2D,MetersLat:Double,MetersLong:Double)->CLLocationCoordinate2D{
        var tempCoord = CLLocationCoordinate2D()
        var tempRegion = MKCoordinateRegionMakeWithdistance(coord,MetersLat,MetersLong);
        var tempSpan = tempRegion.span;
        tempCoord.latitude = coord.latitude + tempSpan.latitudeDelta;
        tempCoord.longitude = coord.longitude + tempSpan.longitudeDelta;
        return tempCoord;
    }

}