Inlight Media - Blog - Using the iOS MapKit framework

custom-pins.m

UIImage *annotationImage = [UIImage imageNamed:@"annotation-image"]; //NOTE: Using a UIImageView will not work
annotationView.image = annotationImage; // NOTE: Make sure annotationView is an instance of MKAnnotationView, not MKPinAnnotation

panning-zooming.m

double zoomLevel = [mapView getZoomLevel]; // getZoomLevel is implemented in the category
  if(zoomLevel > 16) {
    [mapView setCenterCoordinate:[mapView centerCoordinate] zoomLevel:16 animated:YES];
  }
}

retina-images.m

UIGraphicsBeginImageContextWithOptions(CGSizeMake(40, 60), NO, 2); //Set scale factor to 2 to cater for @2x images
[pinBackground drawInRect:CGRectMake(0,0,40,60)];
[pinForeground drawInRect:CGRectMake(4,4,32,32)];
UIImage *pinImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

routing-part-1.m

NSString *url = [NSString stringWithFormat:@"http://maps.google.com/maps?output=dragdir&saddr=%@&daddr=%@", saddr, daddr];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:url]];

routing-part-2.m

(NSArray *)decodePolyLine:(NSMutableString *)encoded {
    [encoded replaceOccurrencesOfString:@"\\\\" withString:@"\\" options:NSLiteralSearch range:NSMakeRange(0, [encoded length])];
  [encoded replaceOccurrencesOfString:@"points:\"" withString:@"" options:NSLiteralSearch range:NSMakeRange(0, [encoded length])];
   
    NSInteger len = [encoded length];
    NSInteger index = 0;
    NSMutableArray *listCoordinates = [[NSMutableArray alloc] init];
    NSInteger lat=0;
    NSInteger lng=0;
    while (index < len - 1) {
        NSInteger b;
        NSInteger shift = 0;
        NSInteger result = 0;
        do {
      b = [encoded characterAtIndex:index++] - 63;
      result |= (b & 0x1f) << shift;
      shift += 5;
        } while (b >= 0x20);
        NSInteger dlat = ((result & 1) ? ~(result >> 1) : (result >> 1));
        lat += dlat;
        shift = 0;
        result = 0;
        do {
      b = [encoded characterAtIndex:index++] - 63;
      result |= (b & 0x1f) << shift;
      shift += 5;
        } while (b >= 0x20);
        NSInteger dlng = ((result & 1) ? ~(result >> 1) : (result >> 1));
        lng += dlng;
        NSNumber *latitude = [[NSNumber alloc] initWithFloat:lat * 1e-5];
        NSNumber *longitude = [[NSNumber alloc] initWithFloat:lng * 1e-5];
        CLLocation *loc = [[CLLocation alloc] initWithLatitude:[latitude floatValue] longitude:[longitude floatValue]];
    [listCoordinates addObject:loc];
    }
   
    return [NSArray arrayWithArray:listCoordinates];
}