在第四步的基础上，我们试着改变下大头针的颜色

//
//  MKPinAnnotationView.h
//  MapKit
//
//  Copyright (c) 2009-2012, Apple Inc. All rights reserved.
//#import <MapKit/MKAnnotationView.h>enum {MKPinAnnotationColorRed = 0,MKPinAnnotationColorGreen,MKPinAnnotationColorPurple
};
typedef NSUInteger MKPinAnnotationColor;@class MKPinAnnotationViewInternal;MK_CLASS_AVAILABLE(NA, 3_0)
@interface MKPinAnnotationView : MKAnnotationView
{
@privateMKPinAnnotationViewInternal *_pinInternal;
}@property (nonatomic) MKPinAnnotationColor pinColor;@property (nonatomic) BOOL animatesDrop;@end

从大头针的头文件中可以看到，它有一个颜色属性我们可以直接使用。

修改下CustomAnnotation.h和其实现文件，代码如下：

//
//  CustomAnnotation.h
//  LBS_002_mapview
//
//  Created by liqun on 13-7-25.
//  Copyright (c) 2013年 Block Cheng. All rights reserved.
//#import <Foundation/Foundation.h>
#import <MapKit/MapKit.h>#define PIN_RED @"Red"
#define PIN_GREEN @"Green"
#define PIN_PURPLE @"Purple"
@interface CustomAnnotation : NSObject<MKAnnotation>@property (nonatomic, assign, readonly)     CLLocationCoordinate2D coordinate;
@property (nonatomic, copy, readonly)       NSString *title;
@property (nonatomic, copy, readonly)       NSString *subtitle;
@property (nonatomic, unsafe_unretained) MKPinAnnotationColor pinColor;
- (id) initWithCoordinates:(CLLocationCoordinate2D)paramCoordinatestitle:(NSString *)paramTitlesubTitle:(NSString *)paramSubTitle;+ (NSString *) reusableIdentifierforPinColor :(MKPinAnnotationColor)paramColor;
@end

//
//  CustomAnnotation.m
//  LBS_002_mapview
//
//  Created by liqun on 13-7-25.
//  Copyright (c) 2013年 Block Cheng. All rights reserved.
//#import "CustomAnnotation.h"@implementation CustomAnnotation- (void)dealloc
{[_subtitle  release];[_title  release];[super dealloc];
}
- (id) initWithCoordinates:(CLLocationCoordinate2D)paramCoordinatestitle:(NSString *)paramTitlesubTitle:(NSString *)paramSubTitle
{if (self = [super init]) {_coordinate = paramCoordinates;_title = [paramTitle copy];_subtitle = [paramSubTitle copy];}return self;
}+ (NSString *) reusableIdentifierforPinColor :(MKPinAnnotationColor)paramColor{ NSString *result = nil;switch (paramColor){case MKPinAnnotationColorRed:{result = PIN_RED;break;}case MKPinAnnotationColorGreen:{result = PIN_GREEN;break;}case MKPinAnnotationColorPurple:{result = PIN_PURPLE;break;}}return result;
}
@end

最后，在ViewControlelr实现文件中，加上该注解类的颜色属性：

//
//  ViewController.m
//  LBS_002_mapview
//
//  Created by liqun on 13-7-25.
//  Copyright (c) 2013年 Block Cheng. All rights reserved.
//#import "ViewController.h"
#import <MapKit/MapKit.h>
#import "CustomAnnotation.h"@interface ViewController ()<CLLocationManagerDelegate,MKMapViewDelegate>
@property (nonatomic,retain)MKMapView* mapView;
@property (nonatomic,retain)CLLocationManager* locationManager;
@property (nonatomic,retain)CLLocation* location;
@property (nonatomic, retain) CLGeocoder *myGeocoder;@end@implementation ViewController- (void)viewDidLoad
{[super viewDidLoad];// Do any additional setup after loading the view, typically from a nib.MKMapView* map = [[MKMapView alloc] initWithFrame:self.view.frame];map.mapType = MKMapTypeStandard;map.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;[self.view addSubview:map];[map release];self.mapView = map;self.mapView.delegate = self;UIButton *addBt = [UIButton buttonWithType:UIButtonTypeRoundedRect];addBt.frame = CGRectMake(0, 00, 320, 50);[addBt setTitle:@"locationMe" forState:UIControlStateNormal];[ addBt addTarget:self action:@selector(handleLocationMe:) forControlEvents:UIControlEventTouchUpInside];[self.view addSubview: addBt];if ([CLLocationManager locationServicesEnabled]){self.locationManager = [[CLLocationManager alloc] init];self.locationManager.delegate = self;self.locationManager.purpose =@"To provide functionality based on user's current location.";[self.locationManager startUpdatingLocation];} else {/* Location services are not enabled.Take appropriate action: for instance, prompt the user to enable location services */NSLog(@"Location services are not enabled");}self.myGeocoder = [[CLGeocoder alloc] init];}- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation:(id <MKAnnotation>)annotation
{MKAnnotationView *result = nil;if ([annotation isKindOfClass:[CustomAnnotation class]] == NO){return result;}if ([mapView isEqual:self.mapView] == NO){/* We want to process this event only for the Map Viewthat we have created previously */return result;}/* First, typecast the annotation for which the Map View hasfired this delegate message */CustomAnnotation *senderAnnotation = (CustomAnnotation *)annotation;/* Using the class method we have defined in our customannotation class, we will attempt to get a reusableidentifier for the pin we are aboutto create */NSString *pinReusableIdentifier =[CustomAnnotation reusableIdentifierforPinColor:senderAnnotation.pinColor];/* Using the identifier we retrieved above, we willattempt to reuse a pin in the sender Map View */MKPinAnnotationView *annotationView = (MKPinAnnotationView *) [mapView dequeueReusableAnnotationViewWithIdentifier:pinReusableIdentifier];if (annotationView == nil){/* If we fail to reuse a pin, then we will create one */annotationView = [[MKPinAnnotationView alloc] initWithAnnotation:senderAnnotation reuseIdentifier:pinReusableIdentifier];/* Make sure we can see the callouts on top ofeach pin in case we have assigned title and/orsubtitle to each pin */[annotationView setCanShowCallout:YES];annotationView.draggable = YES;annotationView.enabled = YES;}/* Now make sure, whether we have reused a pin or created a new one,that the color of the pin matches the color of the annotation */annotationView.pinColor = senderAnnotation.pinColor;//自定义图片时，不能用dropannotationView.animatesDrop = YES;result = annotationView;return result;
}- (void)didReceiveMemoryWarning
{[super didReceiveMemoryWarning];// Dispose of any resources that can be recreated.
}-(IBAction)handleLocationMe:(id)sender
{[self.myGeocoderreverseGeocodeLocation:self.location completionHandler:^(NSArray *placemarks, NSError *error) {if (error == nil &&[placemarks count] > 0){CLPlacemark *placemark = [placemarks objectAtIndex:0];/* We received the results */NSLog(@"Country = %@", placemark.country);NSLog(@"Postal Code = %@", placemark.postalCode);NSLog(@"Locality = %@", placemark.locality);NSLog(@"dic = %@", placemark.addressDictionary );NSLog(@"dic FormattedAddressLines= %@", [placemark.addressDictionary objectForKey:@"FormattedAddressLines"]);NSLog(@"dic Name = %@", [placemark.addressDictionary objectForKey:@"Name"]);NSLog(@"dic State = %@", [placemark.addressDictionary objectForKey:@"State"]);NSLog(@"dic Street = %@", [placemark.addressDictionary objectForKey:@"Street"]);NSLog(@"dic SubLocality= %@", [placemark.addressDictionary objectForKey:@"SubLocality"]);NSLog(@"dic SubThoroughfare= %@", [placemark.addressDictionary objectForKey:@"SubThoroughfare"]);NSLog(@"dic Thoroughfare = %@", [placemark.addressDictionary objectForKey:@"Thoroughfare"]);CLLocationCoordinate2D location =CLLocationCoordinate2DMake(self.location.coordinate.latitude, self.location.coordinate.longitude);/* Create the annotation using the location */CustomAnnotation *annotation =[[CustomAnnotation alloc] initWithCoordinates:location title:placemark.name subTitle:placemark.thoroughfare];/* And eventually add it to the map */annotation.pinColor = MKPinAnnotationColorPurple;[self.mapView addAnnotation:annotation];[annotation release];}else if (error == nil &&[placemarks count] == 0){NSLog(@"No results were returned.");}else if (error != nil){NSLog(@"An error occurred = %@", error);}}];
}- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{/* We received the new location */NSLog(@"Latitude = %f", newLocation.coordinate.latitude);NSLog(@"Longitude = %f", newLocation.coordinate.longitude);self.location = newLocation;}
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error{/* Failed to receive user's location */
}- (void)dealloc
{self.mapView = nil;self.location = nil;self.locationManager = nil;[super dealloc];
}@end

运行后，效果如下：