Getting Oriented with
MapKit
Julio Barros
Julio@E-String.com

Why Maps?
• iPhone is a mobile / pocket computer
• Where am I?
• How do I get somewhere?
• What’s near me?
Julio Barros E-String.com

Dark ages (pre 3.0)
• Static map images
• Web view with Javascript shenanigans
• Exit out to google maps
Julio Barros E-String.com

MapKit
• New in iPhone 3.x
• Embed map in your app
• Uses Google map tiles
• Familiar map UI
Julio Barros E-String.com

Important Classes
MKMapView
MKAnnotation (protocol)
MKAnnotationView
Julio Barros E-String.com

Important Classes
MKMapView
MKMapViewDelegate
MKAnnotation (protocol)
MKAnnotationView
MKPinAnnotationView
Julio Barros E-String.com

Simplest Example
• MKMapView ... just a view
• Or use Interface Builder
• Don’t forget to add mapkit framework
Julio Barros E-String.com

That was
easy
Julio Barros E-String.com

Show User
Location
Julio Barros E-String.com

Showing a
particular area on
the map
Latitude Span
Center
“best fit” not exactly
what you set
Longitude Span
Julio Barros E-String.com

Regions
• MKCoordinateRegion
Julio Barros E-String.com

Denver,
Colorado
Julio Barros E-String.com

Demo data
plist of Brewery information: name, address,
latitude, longitude
Julio Barros E-String.com

Loading Demo Data
Julio Barros E-String.com

Local area
Julio Barros E-String.com

MKAnnotation
Julio Barros E-String.com

MyAnnotation Class
Julio Barros E-String.com

Adding Annotations
Julio Barros E-String.com

Default Pins at
annotations
Julio Barros E-String.com

Customizing pins
• MKPinAnnotationView
• MKMapViewDelegate - set a delegate
Julio Barros E-String.com

Our purple
pins
Julio Barros E-String.com

Custom markers
• MKAnnotationView
Julio Barros E-String.com

Customizing
the view
Julio Barros E-String.com

Customizing the
Callout
Julio Barros E-String.com

Tapping the call out
view
Julio Barros E-String.com

Reverse Geocoding
• Geocoding : address to coordinates
• geocoder.us other services
• Reverse geocoding : coordinates to address
Julio Barros E-String.com

MKReverseGeocoder
Julio Barros E-String.com

MKPlacemark
• Address info including, country code,
country, postal code, administrative area,
sub administrative area, locality, sub locality,
thoroughfare, sub thoroughfare
• Conforms to MKAnnotation
• Has address dictionary with Address Book
keys
Julio Barros E-String.com

Number of pins
• Try to limit
annotations to ~100(?)
• Implement region
change delegate
methods
• Create and manage
your own clusters
Julio Barros E-String.com

Challenges
• Anchoring an object to a location on the
map and having it scale.
• Shapes - neighborhoods
• Lines - routes / paths
• View space to Geo Space
- (CGPoint)convertCoordinate:(CLLocationCoordinate2D)
coordinate toPointToView:(UIView *)view
- (CLLocationCoordinate2D)convertPoint:(CGPoint)point
toCoordinateFromView:(UIView *)view
Julio Barros E-String.com

Legal limitations
I’m not a lawyer but think carefully before using this
for:
vehicle/fleet tracking
routing
cacheing tiles
geocoding / mass reverse geocoding
Read the TOS
http://code.google.com/apis/maps/iphone/
terms.html Julio Barros E-String.com

Possible Options
• OpenStreetMap.org (OSM) - map/tile data
• Route-Me - OSS map view
• Cloudemade.com - services around OSM
• geocoder.us (among others)
Julio Barros E-String.com

Resources
• MapKit Framework Reference - Apple
• Using Map Kit with Bill Dudney - PragProg
• Using Map Kit ... Bill Dudney - Wednesday
Julio Barros E-String.com

Thank You
Julio Barros
Julio@E-String.com
http://www.E-String.com
http://twitter.com/JulioBarros
Also on Face book and Linked In
Julio Barros E-String.com