我想在我的
Swift应用程序中绘制折线.
SWIFT代码
class MapViewController: UIViewController,MKMapViewDelegate {
@IBOutlet var theMapView: MKMapView
override func viewDidLoad() {
super.viewDidLoad()
setMapView()
}
func setMapView() {
//theMapView.zoomEnabled = false
//theMapView.scrollEnabled = false
theMapView.rotateEnabled = false
//
var lat: CLLocationDegrees = 37.586601
var lng: CLLocationDegrees = 127.009381
//
var latDelta: CLLocationDegrees = 0.008
var lngDelta: CLLocationDegrees = 0.008
var theSpan: MKCoordinateSpan = MKCoordinateSpanMake(latDelta,lngDelta)
var initLocation: CLLocationCoordinate2D = CLLocationCoordinate2DMake(lat,lng)
var theRegion: MKCoordinateRegion = MKCoordinateRegionMake(initLocation,theSpan)
self.theMapView.setRegion(theRegion,animated: true)
var locations = [CLLocation(latitude: 37.582691,longitude: 127.011186),CLLocation(latitude: 37.586112,longitude: 127.011047),CLLocation(latitude: 37.588212,longitude: 127.010438)]
var coordinates = locations.map({(location: CLLocation) -> CLLocationCoordinate2D in return location.coordinate})
var polyline = MKPolyline(coordinates: &coordinates,count: locations.count)
var myPolylineView : MKPolylineView
/* error */
myPolylineView.polyline = polyline // #1
myPolylineView.strokeColor = UIColor.blueColor() // #2
myPolylineView.lineWidth = 5; // #3
self.theMapView.addOverlay(myPolylineView) // #4
/* ----- */
}
}
错误：
// #1 <br> Cannot assign to 'polyline' in 'myPolylineView' <br> // #2 <br> 'strokeColor' is unvailable: APIs deprecated as iOS 7 and earlier are unavailable in Swift <br> // #3 <br> 'lineWidth' is unvailable: APIs deprecated as iOS 7 and earlier are unavailable in Swift <br> // #4 <br> Missing argument for parameter 'level' in call <br>
我找不到解决办法.
解决方法
首先,而不是MKPolylineView,您必须创建一个MKPolylineRenderer.
MKPolylineView自iOS 7以来已被弃用,尽管如果需要,您仍然可以在Objective-C中使用它,Swift不支持它.
其次,您必须在rendererForOverlay委托方法中创建并返回MKPolylineRenderer(不将其传递给addOverlay).
在addOverlay方法中,传递MKPolyline对象(不是MKPolylineView或MKPolylineRenderer).
(参见Adding MKOverlayPathRenderer as overlay to MKMapView gets exception,了解您传递给addOverlay的对象与您在rendererForOverlay中返回的对象之间的区别.
所以在setMapView方法中,删除创建和设置myPolylineView的行,并将addOverlay行更改为：
self.theMapView.addOverlay(polyline)
然后实现rendererForOverlay方法：
func mapView(mapView: MKMapView!,rendererForOverlay overlay: MKOverlay!) -> MKOverlayRenderer! {
if overlay is MKPolyline {
var polylineRenderer = MKPolylineRenderer(overlay: overlay)
polylineRenderer.strokeColor = UIColor.blueColor()
polylineRenderer.lineWidth = 5
return polylineRenderer
}
return nil
}
确保地图视图的委托设置,否则代理方法将不会被调用,并且覆盖图不会显示.如果mapView是一个IBOutlet,连接委托插座或将其设置为代码(例如,在调用super后的viewDidLoad中)：
self.theMapView.delegate = self
