Part one of this section on MapKits showed how to embed a map and place a floating toolbar for switching the map views, however it didn’t cover how to drop the pin where you wanted it.

Create the Object

First lets create a new NSObject for the place mark. Let’s call it ‘PlaceMark’

PlaceMark.h

#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>

@interface PlaceMark : NSObject {
	CLLocationCoordinate2D coordinate;
	NSString *subtitletext;
	NSString *titletext;
}
@property (nonatomic, readonly) CLLocationCoordinate2D coordinate;
@property (readwrite, retain) NSString *titletext;
@property (readwrite, retain) NSString *subtitletext;
-(id)initWithCoordinate:(CLLocationCoordinate2D) coordinate;
- (NSString *)subtitle;
- (NSString *)title;
-(void)setTitle:(NSString*)strTitle;
-(void)setSubTitle:(NSString*)strSubTitle;

@end

PlaceMark.m

#import "PlaceMark.h"

@implementation PlaceMark
@synthesize coordinate, titletext, subtitletext;

- (NSString *)subtitle{
	return subtitletext;
}
- (NSString *)title{
	return titletext;
}

-(void)setTitle:(NSString*)strTitle {
	self.titletext = strTitle;
}

-(void)setSubTitle:(NSString*)strSubTitle {
	self.subtitletext = strSubTitle;
}

-(id)initWithCoordinate:(CLLocationCoordinate2D) c{
	coordinate=c;
	return self;
}
@end

Adding a pin to your map

Firstly remember to add

#import "PlaceMark.h"

To your map controller, from the previous example inside the displayMap function under the region.center call

PlaceMark *addAnnotation = [[[PlaceMark alloc] initWithCoordinate:location] retain];
[addAnnotation setTitle:@"The Pin Title"];
[addAnnotation setSubTitle:@"The pin subtitle goes here"];

[mapView addAnnotation:addAnnotation];

Then create the following delegate method

- (MKAnnotationView *) mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>) annotation{
    MKPinAnnotationView *annView=[[MKPinAnnotationView alloc] initWithAnnotation:annotation reuseIdentifier:@"MyPin"];
    annView.animatesDrop=TRUE;
    annView.canShowCallout = YES;
	[annView setSelected:YES];
	annView.pinColor = MKPinAnnotationColorPurple;
    annView.calloutOffset = CGPointMake(-5, 5);
    return annView;
}

Voila you now have a pin dropped on the map and automatically selected. If you don’t want the title automatically displayed then change

[annView setSelected:YES];

The final part demonstrates how to create a mini map

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