问题
I'm trying to use an MKOverlay
(specifically an MKPolyline
) to show a route on the map. However, I need the route to show up above my existing pins (custom MKAnnotationView
s). Is there a good way to bring the MKPolyline
to the front above the pins?
回答1:
It might be useful to investigate the annotation layer's zOrder
property. Sending the annotations backwards in your superview's hierarchy may help you achieve the effect needed. Changing your annotation z-axis position should probably be done within the mapView:didAddAnnotationViews:
delegate method.
- (void)mapView:(MKMapView *)mapView didAddAnnotationViews:(NSArray *)views {
annotationView.layer.zPosition = x;
}
It's been a while since I've dealt with MKPolyline
, and I know things changed a lot in iOS 8, but you might be able to directly manipulate the polyline's z position while you're drawing it.
UPDATE
When you add your MKOverlay
to the map, starting in iOS 7.0+, use the addOverlay:level:
method. This allows you to specify the z-position of the overlay. One of the highest z-positions for the overlay as defined by MKOverlayLevels
is MKOverlayLevelAboveLabels
:
Place the overlay above map labels, shields, or point-of-interest icons but below annotations and 3D projections of buildings.
Unfortunately, as mentioned in the documentation above, the map does not support placing overlays above annotations. A possible solution may be to add the annotations to a separate MKOverlay
object and then to add the other overlay (with the path) to the map using insertOverlay:aboveOverlay:
.
来源:https://stackoverflow.com/questions/33240855/how-do-i-show-mkoverlay-above-mkannotations