how to handle multiple MKOverlays in delegate function - ios

Question

I want to have a MKMapView with an two different overlays.
First, I have an "Image Overlay on the Map" (TileOverlay),
and secondly I want to draw a route as an overlay on the Map.
Everything works fine if I do this stuff in two different projects (One with the image overlay, and the other with the route overlay)
Now, I am wondering how the viewForOverlay delegate function should look like if I merge my projects?
For my Image (tile) overlay i currently looks like this:
- (MKOverlayView *) mapView:(MKMapView *)mapView viewForOverlay:(id <MKOverlay>)overlay
{
TileOverlayView *tileView = [[TileOverlayView alloc] initWithOverlay:overlay];
tileView.tileAlpha = 1.0;
return tileView;
}
For my route Overlay it looks like this:
- (MKOverlayView*)mapView:(MKMapView *)mapView viewForOverlay:(id<MKOverlay>)overlay
{
MKPolylineView *polylineView = [[MKPolylineView alloc] initWithPolyline:overlay];
polylineView.lineJoin = kCGLineJoinRound;
polylineView.strokeColor = [[UIColor blueColor] colorWithAlphaComponent:0.4];
return polylineView;
}
Now if i want to "merge" these (into one Project), how should this method look like?
- (MKOverlayView*)mapView:(MKMapView *)mapView viewForOverlay:(id<MKOverlay>)overlay
{
//what comes here?
}

Answer 1

You could deal with this situation by first checking the type of the overlay passed into your mapView:viewForOverlay: method, like this:
- (MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id <MKOverlay>)overlay {
if ([overlay isKindOfClass:[MKPolyline class]]) {
MKPolylineView *polylineView = [[MKPolylineView alloc] initWithPolyline:overlay];
polylineView.lineJoin = kCGLineJoinRound;
polylineView.strokeColor = [[UIColor blueColor] colorWithAlphaComponent:0.4];
return polylineView;
} else {
TileOverlayView *tileView = [[TileOverlayView alloc] initWithOverlay:overlay];
tileView.tileAlpha = 1.0;
return tileView;
}