Adding a Map to an App and recording a User’s location as they use the App has become a common must have feature in may of todays popular applications. This presentation will go over the APIs for accomplishing such tasks including map annotations, dragging and dropping custom pins as well as delve into some of the finer aspects of the required location based calculations one needs to consider to find the center of the map or the distance between two points. Additionally the presentation will go over techniques to update a MapView with a moving object as well as positioning the image for the object properly along its heading. This will be a straight forward hands on development presentation with plenty of code examples.

1. Keeping Track
of Moving Things
MapKit and CoreLocation in Depth

2. Today’s Agenda
Working with MapKit in iOS
Working with CoreLocation in iOS
Battery Performance with GPS
Some Basic GPS Tools for Mac
What to expect with iOS 6

3. Getting Started
Adding MapKit Framework to a Target
Designing a View with MapView
How to Center the MapView to a Location

4. Select
Project
Target
Click Add +

5. Add a MapView to a View

6. Drop MapView on
ViewController

7. Establish a Referencing Outlet

8. Create a
Referencing
Outlet

10. Center the Map at a Location

11. CLLocationCoordinate2D location = {40.30444, -82.69556};
[myMapView setRegion:MKCoordinateRegionMakeWithDistance(
location,300000, 300000) animated:YES];
1

13. Adding Annotations to a MapView
Annotating a Map
Custom Pins and Annotations
Supporting Drag and Drop

14. Create a MKAnnotation

15. #import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>
@interface GGTestMapAnnotation : NSObject <MKAnnotation> {
CLLocationCoordinate2D _coordinate;
}
- (id)initWithCoordinate:(CLLocationCoordinate2D)coordinate;
@end
#import "GGTestMapAnnotation.h"
#import <MapKit/MapKit.h>
@implementation GGTestMapAnnotation
@synthesize coordinate=_coordinate;
- (id)initWithCoordinate:(CLLocationCoordinate2D)coordinate{
self = [super init];
if (self != nil) {
_coordinate = coordinate;
}
return self;
}
@end

16. Add an Annotation to the Map

17. [myMapView addAnnotation:[[GGTestMapAnnotation alloc]
initWithCoordinate:location]];
2

19. Become a MKMapViewDelegate

20. Create a
Delegate Outlet

21. @interface GGFirstViewController : UIViewController
<MKMapViewDelegate>
[myMapView setDelegate:self];
- (MKAnnotationView *) mapView:(MKMapView *) mapView
viewForAnnotation: (id) annotation {
MKPinAnnotationView *customAnnotationView =
[[[MKPinAnnotationView alloc]
initWithAnnotation:annotation reuseIdentifier:nil]
autorelease];
return customAnnotationView;
}
3

22. Customize the Pin

23. [customAnnotationView setPinColor:MKPinAnnotationColorPurple];
[customAnnotationView setAnimatesDrop:YES];
4

25. Create a Custom Pin Image

26. MKAnnotationView *customAnnotationView =
[[[MKAnnotationView alloc]
initWithAnnotation:annotation reuseIdentifier:nil]
autorelease];
[customAnnotationView
setImage:[UIImage imageNamed:@"blue-arrow.png"]];
5

28. Supporting Drag and Drop

29. - (void)setCoordinate:(CLLocationCoordinate2D)newCoordinate;
- (void)setCoordinate:(CLLocationCoordinate2D)newCoordinate{
_coordinate = newCoordinate;
}
[customAnnotationView setDraggable:YES];
6

30. Do Something when Dropped

31. - (void)mapView:(MKMapView *)mapView
annotationView:(MKAnnotationView *)annotationView
didChangeDragState:(MKAnnotationViewDragState)newState
fromOldState:(MKAnnotationViewDragState)oldState
{
if (newState == MKAnnotationViewDragStateEnding)
{
NSLog(@"Do something when annotation is dropped");
}
}
7

33. Customizing Annotation Callouts
Add and Auto Display Callout
Add an Image and a Button to the Callout
Do Something when Tapped

34. Add a Callout

35. - (NSString*) title;
- (NSString*) subtitle;
- (NSString*) title{
return @"CocoaConf 2012";
}
- (NSString*) subtitle{
return @"Columbus, OH";
}
[customAnnotationView setCanShowCallout:YES];
8

36. Auto Display Callout

37. - (void)mapView:(MKMapView *)mapView
didAddAnnotationViews:(NSArray *)views
{
[myMapView selectAnnotation:
[[myMapView annotations] lastObject] animated:YES];
}
9

39. Add an Image to the Callout

40. UIImageView *leftIconView =
[[UIImageView alloc] initWithImage:
[UIImage imageNamed:@"m3-conference-left-callout.png"]];
[customAnnotationView
setLeftCalloutAccessoryView:leftIconView];
10

42. Add a Button to the Callout

43. UIButton* rightButton =
[UIButton buttonWithType:UIButtonTypeDetailDisclosure];
[customAnnotationView
setRightCalloutAccessoryView:rightButton];
11

44. Do Something when Tapped

45. - (void)mapView:(MKMapView *) mapView
annotationView:(MKAnnotationView *)view
calloutAccessoryControlTapped:(UIControl *)control
{
NSLog(@"Do Something when tapped");
}
12

47. Working with CoreLocation
Working with Multiple Points
Drawing a Line Between Points
Determine the Distance and Direction

48. Select
Project
Target
Click Add +

49. Core Location Data Types
typedef struct {
! CLLocationDegrees latitude;
! CLLocationDegrees longitude;
} CLLocationCoordinate2D;
CLLocationDegrees - is a - double
CLLocationDirection - is a - double
CLLocationDistance - is a - double
CLLocationAccuracy - is a - double

50. Working with Multiple Points

51. double pointOneLatitude = 39.13333;
double pointOneLongitude = -84.50000;
CLLocationCoordinate2D pointOneCoordinate =
{pointOneLatitude, pointOneLongitude};
[myMapView addAnnotation:[[[GGTestMapAnnotation alloc]
initWithCoordinate:pointOneCoordinate] autorelease]];
double pointTwoLatitude = 40.30444;
double pointTwoLongitude = -82.69556;
CLLocationCoordinate2D pointTwoCoordinate =
{pointTwoLatitude, pointTwoLongitude};
[myMapView addAnnotation:[[[GGTestMapAnnotation alloc]
initWithCoordinate: pointTwoCoordinate] autorelease]];
13

53. Drawing a Line Between Points

54. MKMapPoint pointOne =
MKMapPointForCoordinate(pointOneCoordinate);
MKMapPoint pointTwo =
MKMapPointForCoordinate(pointTwoCoordinate);
MKMapPoint *pointsArray =
malloc(sizeof(CLLocationCoordinate2D) * 2);
pointArray[0] = pointOne;
pointArray[1] = pointTwo;
MKPolyline *routeLine =
[MKPolyline polylineWithPoints:pointsArray count:2];
[self.myMapView addOverlay:routeLine];
14

55. - (MKOverlayView *) mapView:(MKMapView *) mapView
viewForOverlay:(id) overlay {
if ([overlay isKindOfClass:[MKPolyline class]]){
MKPolylineView *polylineView =
[[MKPolylineView alloc] initWithPolyline:overlay];
[polylineView setFillColor:[UIColor blueColor]];
[polylineView setStrokeColor:[UIColor blueColor]];
[polylineView setLineWidth:3];
MKOverlayView *overlayView = polylineView;
return overlayView;
}else {
return nil;
}
}
15

57. Determine the Distance

58. CLLocation *pointOneLocation = [[CLLocation alloc]
initWithLatitude: pointOneCoordinate.latitude
longitude: pointOneCoordinate.longitude];
CLLocation *pointTwoLocation = [[CLLocation alloc]
initWithLatitude: pointTwoCoordinate.latitude
longitude: pointTwoCoordinate.longitude];
CLLocationDistance meters = [pointOneLocation
distanceFromLocation: pointTwoLocation];
16

60. Determine the Direction

61. double lat1 = pointOneCoordinate.latitude * M_PI / 180.0;
double lon1 = pointOneCoordinate.longitude * M_PI / 180.0;
double lat2 = pointTwoCoordinate.latitude * M_PI / 180.0;
double lon2 = pointTwoCoordinate.longitude * M_PI / 180.0;
double dLon = lon2 - lon1;
double y = sin(dLon) * cos(lat2);
double x = cos(lat1) * sin(lat2) -
sin(lat1) * cos(lat2) * cos(dLon);
double radiansBearing = atan2(y, x);
CLLocationDirection directionBetweenPoints =
radiansBearing * 180.0/M_PI;
17

63. Battery Performance with GPS

64. Some Basic Tools for Mac
Translating GPS Data
HoudahGPS (based on GPSBabel)
Working with GPS Tracks
myTracks or RouteBuddy
Translating GPS Coordinates
http://maps2.nris.mt.gov/topofinder1/LatLong.asp
The Google Geocoding API
http://code.google.com/apis/maps/documentation/geocoding/