简易绘制地图路线
当我们获取了一组地理位置后，可能会想要在地图上绘制这组地理位置信息所包含的路线。
MKMapView提供了addOverlay功能（以及addAnnotation），让我们可以在地图上放一层遮罩。如果要放一组遮罩，可以用addOverlays。
- #pragma mark –
- – (void)drawLineWithLocationArray:(NSArray *)locationArray
- {
- int pointCount = [locationArray count];
- CLLocationCoordinate2D *coordinateArray = (CLLocationCoordinate2D *)malloc(pointCount * sizeof(CLLocationCoordinate2D));
- for (int i = 0; i < pointCount; ++i) {
- CLLocation *location = [locationArray objectAtIndex:i];
- coordinateArray[i] = [location coordinate];
- }
- self.routeLine = [MKPolyline polylineWithCoordinates:coordinateArray count:pointCount];
- [self.mapView setVisibleMapRect:[self.routeLine boundingMapRect]];
- [self.mapView addOverlay:self.routeLine];
- free(coordinateArray);
- coordinateArray = NULL;
- }
MKPolyLine为我们提供了方便绘制多条线段的功能，它实现了MKOverlay协议，但并不能作为遮罩。我们需要实现相应的遮罩代理方法：
- #pragma mark – MKMapViewDelegate
- – (MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id<MKOverlay>)overlay
- {
- if(overlay == self.routeLine) {
- if(nil == self.routeLineView) {
- self.routeLineView = [[[MKPolylineView alloc] initWithPolyline:self.routeLine] autorelease];
- self.routeLineView.fillColor = [UIColor redColor];
- self.routeLineView.strokeColor = [UIColor redColor];
- self.routeLineView.lineWidth = 5;
- }
- return self.routeLineView;
- }
- return nil;
- }
下面是我的测试代码，用北京的经纬度和杭州的经纬度画线：
- – (void)drawTestLine
- {
- CLLocation *location0 = [[CLLocation alloc] initWithLatitude:39.954245 longitude:116.312455];
- CLLocation *location1 = [[CLLocation alloc] initWithLatitude:30.247871 longitude:120.127683];
- NSArray *array = [NSArray arrayWithObjects:location0, location1, nil];
- [self drawLineWithLocationArray:array];
- }
转载自：https://blog.csdn.net/rebornyoung/article/details/8969632
