相关疑难解决方法(0)

我将两个不同的MKGeodesicPolyline实例添加到MKMapView这样的

CLLocation *LAX = [[CLLocation alloc] ...];
CLLocation *JFK = [[CLLocation alloc] ...];
CLLocation *LHR = [[CLLocation alloc] ...];

CLLocationCoordinate2D laxToJfkCoords[2] = {LAX.coordinate, JFK.coordinate};
CLLocationCoordinate2D jfkToLhrCoords[2] = {JFK.coordinate, LHR.coordinate};

MKGeodesicPolyline *laxToJfk = [MKGeodesicPolyline polylineWithCoordinates:laxToJfkCoords count:2];
MKGeodesicPolyline *jfkToLhr = [MKGeodesicPolyline polylineWithCoordinates:jfkToLhrCoords count:2];

[mapView addOverlay:laxToJfk];
[mapView addOverlay:jfkToLhr];

我想用需要在rendererForOverlay委托方法中配置的不同样式来渲染这两个叠加层。

- (MKOverlayRenderer *)mapView:(MKMapView *)mapView rendererForOverlay:(id <MKOverlay>)overlay {
    if (![overlay isKindOfClass:[MKPolyline class]]) {
        return nil;
    }

    MKPolylineRenderer *renderer = [[MKPolylineRenderer alloc] initWithPolyline:(MKPolyline *)overlay];
    renderer.lineWidth = 3.0f;

    // How to …