Add Overlay to Mapview

Question

I have been doing iOS dev for a few months. I already have a map view with a couple of annotations pinned to it and can show the users current location.

I haven been trying to read through the docs to implement a simple overlay using a set of CLLocationCoordinate2D to draw out a line (simple static route). Its has been a struggle

My MkOverlayRenderer method doesnt seem to be running at all. If I am not mistaking i shouldn't need the MKMapViewDelegate. I am trying to implement MKOverlay delegate and have "@synthesize boundingMapRect;".

Here is my code for trying to implement the Overlay

- (void)drawLineRoute
{
    CLLocationCoordinate2D purplePoints[2];
    purplePoints[0] = CLLocationCoordinate2DMake(28.541944, -81.382936);
    purplePoints[1] = CLLocationCoordinate2DMake(28.538447, -81.383096);

    MKPolyline *purplePolyline = [MKPolyline         polylineWithCoordinates:purplePoints count:2];
    purplePolyline.title = @"Citrus Bowl Connection";

[self.mapView addOverlay:purplePolyline];
}

- (MKOverlayRenderer *)mapView:(MKMapView *)mapView viewForOverlay:  (id<MKOverlay>)overlay
{
if([overlay isKindOfClass:[MKPolyline class]])
{
    MKPolygonRenderer *polyRender = [[MKPolygonRenderer alloc] initWithOverlay:overlay];
    polyRender.lineWidth = 2;
    polyRender.strokeColor = ovoPurple;
    return polyRender;
}

return nil;
}

Any help or guidance is greatly appreciated. Thank you all in advance.

You should let your viewcontroller implement `MKMapViewDelegate`, also set `self.mapView.delegate = self;`. From iOS 7, you should use 'rendererForOverlay` method instead of `viewForOverlay`. — ztan, May 14 '15 at 20:51
I thought I did it through the story board but i guess i didnt. Adding : 'self.mapView.delegate = self;' to my view did load caused this view to crash. This view controller is now giving me a warning "Assigning to 'id' from incompatible type 'ShuttleMapViewController *const__strong' — wambambizzle, May 14 '15 at 21:10

Rob · Accepted Answer · 2015-05-14T21:20:54.197

There are two different delegate methods:

mapView:rendererForOverlay:, which was introduced in iOS 7, and returns a MKOverlayRenderer; and
mapView:viewForOverlay:, which was deprecated in iOS 7, but it returns a MKOverlayView, not a MKOverlayRenderer.

It is incorrect to implement a viewForOverlay that returns a MKOverlayRenderer.

Bottom line, if you need to support iOS versions prior to iOS 7, implement viewForOverlay that returns a MKOverlayView, not a MKOverlayRenderer. If you don't need to support iOS versions prior to 7, then do not implement viewForOverlay at all, but rather implement rendererForOverlay that returns a MKOverlayRenderer.

Thank you all so much! I needed to add the delegate in my viewdidload. And i fixed the renderForOverlay in my rendermethod. — wambambizzle, May 14 '15 at 21:27

Add Overlay to Mapview

1 Answers1