showsUserLocation action attached to button not working - ios8

Question

I am having problems with a map view in my app. I have created a button that when clicked should show users location on the map, but nothing happens (no error messages occur).
I believe the issue may lie in the way I've written the delegates. The code from the relevant .h and .m files is below:
mapViewController.h
#import <UIKit/UIKit.h>
#import <MapKit/MapKit.h>
#import <CoreLocation/CoreLocation.h>
#interface mapViewController : UIViewController {
MKMapView *mapview;
}
#property (nonatomic, retain) IBOutlet MKMapView *mapview;
-(IBAction)setMap:(id)sender;
-(IBAction)getCurrentLocation:(id)sender;
#property (nonatomic, retain) IBOutlet CLLocationManager *locationManager;
#end
mapViewController.m
#import "mapViewController.h"
#interface mapViewController ()
#end
#implementation mapViewController {
CLLocationManager *locationManager;
}
#synthesize mapview;
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view.
self.locationManager.delegate=self;
self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
self.locationManager.requestWhenInUseAuthorization;
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
-(IBAction)setMap:(id)sender {
switch (((UISegmentedControl *) sender).selectedSegmentIndex) {
case 0:
mapview.mapType = MKMapTypeStandard;
break;
case 1:
mapview.mapType = MKMapTypeSatellite;
break;
case 2:
mapview.mapType = MKMapTypeHybrid;
break;
default:
break;
}
}
-(IBAction)getCurrentLocation:(id)sender {
mapview.showsUserLocation = YES;
}
#end
Any help would be greatly appreciated, thanks

Answer 1

You have to implement the MapKit delegates. (Make sure you add the delegate signature in .h of your view controller)
- (void)mapView:(MKMapView *)mapView didUpdateUserLocation:(MKUserLocation *)userLocation {
MKCoordinateRegion region;
MKCoordinateSpan span;
span.latitudeDelta = 0.005;
span.longitudeDelta = 0.005;
CLLocationCoordinate2D location;
location.latitude = userLocation.coordinate.latitude;
location.longitude = userLocation.coordinate.longitude;
region.span = span;
region.center = location;
[mapView setRegion:region animated:YES];
}
Extra: To handle App is on foreground or not:
We add 2 event observers to observe the App is entering background / returning active:
- (void)viewDidLoad{
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(appToBackground) name:UIApplicationDidEnterBackgroundNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(appReturnsActive) name:UIApplicationDidBecomeActiveNotification object:nil];
}
- (void)appToBackground{
[mapview setShowsUserLocation:NO];
}
- (void)appReturnsActive{
[mapview setShowsUserLocation:YES];
}