MapView demo

MapView.m

//
//  ViewController.m
//  Map Hacks
//
//  Created by Ken Woo on 2016-02-02.
//  Copyright © 2016 Lighthouse Labs. All rights reserved.
//

#import "ViewController.h"
#import <CoreLocation/CoreLocation.h>
#import <MapKit/MapKit.h>

@interface ViewController () <CLLocationManagerDelegate, MKMapViewDelegate>

@property (assign, nonatomic) BOOL initialLocationSet;
@property (strong, nonatomic) CLLocationManager *locationManager;
@property (strong, nonatomic) IBOutlet MKMapView *mapView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    
    // Set our view controller to be the mapView's delegate
    self.mapView.delegate = self;
    
    // We are going to use this property to zoom in on the user's initial location only once
    self.initialLocationSet = NO;
    
    // Create an instance of your location manager and be its delegate
    self.locationManager = [[CLLocationManager alloc] init];
    self.locationManager.delegate = self;
    
    // Some ways to change how often we get updated or how accurate we need to be
    //self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
    //self.locationManager.distanceFilter = 50;
    
    
    // Request for the user's permission if we have not done so
    if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusNotDetermined) {
        // Make the actual request. This will FAIL if you are missing the NSLocationWhenInUseUsageDescription key from the Info.plist
        [self.locationManager requestWhenInUseAuthorization];
    }
    
    // Load some bike stations
    [self loadBikeStationsJSON];
}

- (void)loadBikeStationsJSON {
    // Load the bikeStations.json from a local file
    NSString *jsonPath =[[NSBundle mainBundle] pathForResource:@"bikeStations" ofType:@"json"];
    NSData *jsonData = [NSData dataWithContentsOfFile:jsonPath];
    
    NSError *error = nil;
    NSDictionary *stationDict = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers error:&error];
    if (!error) {
        NSArray *stations = stationDict[@"stationBeanList"];
        
        // For each station, create an annotation and add it on the map after setting up some properties
        for (NSDictionary *station in stations) {
            
            MKPointAnnotation *marker = [[MKPointAnnotation alloc] init];
            
            marker.coordinate = CLLocationCoordinate2DMake([station[@"latitude"] doubleValue], [station[@"longitude"] doubleValue]);
            marker.title = station[@"stationName"];
            marker.subtitle = station[@"statusValue"];
            
            [self.mapView addAnnotation:marker];
        }
    }
}

#pragma mark CLLocationManagerDelegate

- (void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status {
    NSLog(@"Authorization changed");
    
    // If the user's allowed us to use their location, we can start getting location updates
    if (status == kCLAuthorizationStatusAuthorizedWhenInUse) {
        [self.locationManager startUpdatingLocation];
    }
}

- (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray<CLLocation *> *)locations {
    
    // Get the last object from the list of locations we get back
    CLLocation *userLocation = [locations lastObject];
    
    // Only do the zoom in once
    if (!self.initialLocationSet) {
        self.initialLocationSet = YES;
        
        // Create a region around the user's location
        CLLocationCoordinate2D userCoordinate = userLocation.coordinate;
        MKCoordinateRegion userRegion = MKCoordinateRegionMake(userCoordinate, MKCoordinateSpanMake(0.01, 0.01));
        
        // Tell our map view to zoom in to that region
        [self.mapView setRegion:userRegion animated:YES];
        
        // We can tell our location manager to stop updating locations
        // [self.locationManager stopUpdatingLocation];
        
        // Use a CLGeocoder to determine a GPS coordinate from an address string
        CLGeocoder *geoCoder = [[CLGeocoder alloc] init];
        [geoCoder geocodeAddressString:@"46 Spadina, Toronto" completionHandler:^(NSArray<CLPlacemark *> * _Nullable placemarks, NSError * _Nullable error) {
            if (!error) {
                // The Placemark will have information about the location, like the coordinates, postal code, etc.
                CLPlacemark *placemark = [placemarks lastObject];
                NSLog(@"%@", placemark);
            }
        }];
        
        // Use a MKLocalSearch to do a map search
        MKLocalSearchRequest *searchRequest = [[MKLocalSearchRequest alloc] init];
        searchRequest.naturalLanguageQuery = @"Smoke's Poutinerie";
    
        MKLocalSearch *localSearch = [[MKLocalSearch alloc] initWithRequest:searchRequest];
        [localSearch startWithCompletionHandler:^(MKLocalSearchResponse * _Nullable response, NSError * _Nullable error) {
            
            // We get back a bunch of map items, map items have a placemark property with information similar to what we get from CLGeoCoder
            MKMapItem *mapItem = [response.mapItems lastObject];
            CLPlacemark *placemark = mapItem.placemark;
            NSLog(@"%@", placemark);
        }];
    }
    NSLog(@"%@", locations);
}

#pragma mark MKMapViewDelegate


- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id<MKAnnotation>)annotation {
    
    // Don't customize user's location annotation
    if (annotation == mapView.userLocation) {
        return nil;
    }
    
    // Create our own annotations and customize the image
    MKAnnotationView *pinView = [mapView dequeueReusableAnnotationViewWithIdentifier:@"BikeStation"];
    if (!pinView) {
        pinView = [[MKAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"BikeStation"];
        pinView.image = [UIImage imageNamed:@"bikeStation.png"];
        pinView.centerOffset = CGPointMake(0, -pinView.image.size.height/2);
        pinView.canShowCallout = YES;
    }
    
    return pinView;
}

- (void)mapView:(MKMapView *)mapView didSelectAnnotationView:(MKAnnotationView *)view {
    
}

- (void)mapView:(MKMapView *)mapView annotationView:(MKAnnotationView *)view calloutAccessoryControlTapped:(UIControl *)control {
    
}


@end