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>
我找不到解决方案。
首先 ,MKPolylineView必须创建一个MKPolylineRenderer。
MKPolylineView
MKPolylineRenderer
MKPolylineView 自iOS 7起已弃用,尽管您仍可以在Objective-C中使用它,但在Swift中不支持它。
其次 ,您必须MKPolylineRenderer在rendererForOverlay委托方法中创建并返回一个(不要将其传递给addOverlay)。
rendererForOverlay
addOverlay
在addOverlay方法中,传递MKPolyline对象(而不是MKPolylineViewor MKPolylineRenderer)。
MKPolyline
以解释传递给addOverlay哪个对象与返回的对象之间的区别rendererForOverlay。)
因此,在该setMapView方法中,删除创建和设置的行,myPolylineView并将其更改addOverlay为:
setMapView
myPolylineView
self.theMapView.addOverlay(polyline)
然后实现该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 }
确保设置了地图视图,delegate否则将不会调用委托方法,并且不会显示叠加层。如果theMapView是IBOutlet,则连接delegate插座或将其设置为代码(例如,viewDidLoad在调用super之后输入):
delegate
theMapView
viewDidLoad
self.theMapView.delegate = self