overlay map view not showing up - ios

Question

I'm trying to make a MKMapView and add and overlay to it using coordinates.
It is not showing up in the mapView.
it seems to be compiling ok but when I open the mapView view in the storyboard I see the map of the world but there is no red overlay anywhere.
Here is my code.
my header
#import <UIKit/UIKit.h>
#import <CoreLocation/CoreLocation.h>
#import <AVFoundation/AVFoundation.h>
#import <CoreMotion/CoreMotion.h>
#import <MapKit/MapKit.h>
NS_ASSUME_NONNULL_BEGIN
#interface mapViewController : UIViewController<CLLocationManagerDelegate,MKMapViewDelegate>
#property (nonatomic, retain) IBOutlet MKMapView *mapView;
#property(nonatomic, retain) MKPolygon *polygon;
#end
and my .m file
#import "mapViewController.h"
#interface mapViewController ()
#end
#implementation mapViewController
#synthesize mapView,locationManager,polygon;
- (void)viewDidLoad {
[super viewDidLoad];
mapView.delegate = self;
NSDictionary *d1=[NSDictionary dictionaryWithObjectsAndKeys:#"37.57111111",#"x",#"-109.52166667",#"y",nil];
NSDictionary *d2=[NSDictionary dictionaryWithObjectsAndKeys:#"32.01138889",#"x",#"-109.59000000",#"y",nil];
NSDictionary *d3=[NSDictionary dictionaryWithObjectsAndKeys:#"31.83166667",#"x",#"-111.95416667",#"y",nil];
NSDictionary *d4=[NSDictionary dictionaryWithObjectsAndKeys:#"32.34250000",#"x",#"-115.14333333",#"y",nil];
NSDictionary *d5=[NSDictionary dictionaryWithObjectsAndKeys:#"34.89722222",#"x",#"-115.47611111",#"y",nil];
NSDictionary *d6=[NSDictionary dictionaryWithObjectsAndKeys:#"37.32083333",#"x",#"-116.02027778",#"y",nil];
NSDictionary *d7=[NSDictionary dictionaryWithObjectsAndKeys:#"37.53305556",#"x",#"-114.73416667",#"y",nil];
NSDictionary *d8=[NSDictionary dictionaryWithObjectsAndKeys:#"37.53166667",#"x",#"-114.11277778",#"y",nil];
NSDictionary *d9=[NSDictionary dictionaryWithObjectsAndKeys:#"37.57111111",#"x",#"-109.52166667",#"y",nil];
NSArray *azcoord = [NSArray arrayWithObjects:d1,d2,d3,d4,d5,d6,d7,d8, nil];
CLLocationCoordinate2D coordinates[azcoord.count];
int coordinatesIndex = 0;
for (NSDictionary * c in azcoord) {
double x = [[c valueForKey:#"x"] doubleValue];
double y = [[c valueForKey:#"y"] doubleValue];
CLLocationCoordinate2D coordinate;
coordinate.latitude = y;
coordinate.longitude = x;
//Put this coordinate in the C array...
coordinates[coordinatesIndex] = coordinate;
coordinatesIndex++;
}
polygon = [MKPolygon polygonWithCoordinates:coordinates count:azcoord.count];
[self.mapView addOverlay:polygon];
}
- (MKOverlayRenderer *)mapView:(MKMapView *)mapView rendererForOverlay:(id<MKOverlay>)overlay
{
MKPolygonRenderer *renderer = [[MKPolygonRenderer alloc] initWithPolygon:polygon];
renderer.fillColor = [[UIColor redColor] colorWithAlphaComponent:1];
renderer.strokeColor = [[UIColor blackColor] colorWithAlphaComponent:0.7];
renderer.lineWidth = 2;
return renderer;
}
#end
what I am trying to do is draw an overlay for the state of Arizona. I've checked the coordinates and they are correct.
Eventually I want to create overlays for all states.
can anyone see where I'm going wrong?

Answer 1

I figured it out by changing my approach. Here is my code that is working.
first i create a CLLocationCoordinate2D array of my coordinates and make them into a polygon. then add to mapView.
CLLocationCoordinate2D points[7];
points [0] = CLLocationCoordinate2DMake(36.99910000, -109.04520000);
points [1] = CLLocationCoordinate2DMake(31.33460000, -109.05220000);
points [2] = CLLocationCoordinate2DMake(31.33700000, -111.07720000);
points [3] = CLLocationCoordinate2DMake(32.49410000, -114.81360000);
points [4] = CLLocationCoordinate2DMake(36.10660000, -114.75180000);
points [5] = CLLocationCoordinate2DMake(36.21600000, -114.03940000);
points [6] = CLLocationCoordinate2DMake(37.00150000, -114.04820000);
polygon = [MKPolygon polygonWithCoordinates:points count:7];
[self.mapView addOverlay:polygon];
then I render that to the map view.
- (MKOverlayRenderer *)mapView:(MKMapView *)mapView rendererForOverlay:(id<MKOverlay>)overlay
{ NSLog(#"YES!!!!!!!!!!!!!!!!!");
MKPolygonRenderer *renderer = [[MKPolygonRenderer alloc] initWithPolygon:polygon];
renderer.fillColor = [[UIColor redColor] colorWithAlphaComponent:0.2];
renderer.strokeColor = [[UIColor blackColor] colorWithAlphaComponent:0.7];
renderer.lineWidth = 1;
return renderer;
}
then I check to see if my location is inside the polygon.
CLLocationCoordinate2D sampleLocation = CLLocationCoordinate2DMake(myLatitude,myLongitude);//13,80 is the latlong of clear colored area of the MKPolygon in the below image.
MKMapPoint mapPoint = MKMapPointForCoordinate(sampleLocation);
CGPoint mapPointAsCGP = CGPointMake(mapPoint.x, mapPoint.y);
for (id<MKOverlay> polygon in mapView.overlays) {
if([polygon isKindOfClass:[MKPolygon class]]){
NSLog(#"YES<<<<<<<<<<<<<<<<<<");
MKPolygon *polygons = (MKPolygon*) polygon;
CGMutablePathRef mpr = CGPathCreateMutable();
MKMapPoint *polygonPoints = polygons.points;
for (int p=0; p < polygons.pointCount; p++){
MKMapPoint mp = polygonPoints[p];
if (p == 0)
CGPathMoveToPoint(mpr, NULL, mp.x, mp.y);
else
CGPathAddLineToPoint(mpr, NULL, mp.x, mp.y);
}
if(CGPathContainsPoint(mpr , NULL, mapPointAsCGP, TRUE)){
NSLog(#"YES?????????????????????????????????");
//do something else
}
CGPathRelease(mpr);
}
}
I at first didn't want to add a map view but then decided I need to and now that I have I like it.