1、添加地图

1.1 新一个Single View app ，选择默认项，创建后，在ViewController.h

#import <UIKit/UIKit.h>
#import <MapKit/MapKit.h>
#import <CoreLocation/CoreLocation.h>

@interface ViewController : UIViewController 
<MKMapViewDelegate, CLLocationManagerDelegate> {
    MKMapView *map;
    CLLocationManager *locationManager;
}
@end

1.2在ViewController.m中添加

- (void)viewDidLoad
{
    map = [[MKMapView alloc] initWithFrame:[self.view bounds]];
	map.showsUserLocation = YES;
	map.mapType = MKMapTypeSatellite;
    [self.view addSubview:map];


    [super viewDidLoad];
	// Do any additional setup after loading the view, typically from a nib.
}

运行：

OMG,看到的是世界地图。怎么定位到指定的位置呢？比如定位回来伟大的祖国首都？

这里map.mapType =MKMapTypeSatellite;我用到是卫星地图，可以使用标准的地图，

map.mapType =MKMapTypeStandard;

注意，如果此时你编译有错误，请拉到博客最后查看：5、遇到的问题

2、定位到指定经纬度

CLLocationCoordinate2D coords = CLLocationCoordinate2DMake(39.915352,116.397105);
	
	float zoomLevel = 0.02;
	MKCoordinateRegion region = MKCoordinateRegionMake(coords, MKCoordinateSpanMake(zoomLevel, zoomLevel));
	[map setRegion:[map regionThatFits:region] animated:YES];

这样，就我们就定位的了故宫了。

3、添加标注大头针

3.1 新建一个标注类：CustomAnnotation

按Command+N，继承NSObject。在CustomAnnotation.h 和CustomAnnotation.m文件添加如下代码：

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

@interface CustomAnnotation : NSObject 
<MKAnnotation>
{
	CLLocationCoordinate2D coordinate;
	NSString *title;
	NSString *subtitle;
}
-(id) initWithCoordinate:(CLLocationCoordinate2D) coords;

@property (nonatomic, readonly) CLLocationCoordinate2D coordinate;
@property (nonatomic, retain) NSString *title;
@property (nonatomic, retain) NSString *subtitle;

@end

#import "CustomAnnotation.h"

@implementation CustomAnnotation
@synthesize coordinate, title, subtitle;

-(id) initWithCoordinate:(CLLocationCoordinate2D) coords
{
	if (self = [super init]) {
		coordinate = coords;
	}
	return self;
}
@end

3.1 使用大头针，

新建个方法添加大头针的

-(void)createAnnotationWithCoords:(CLLocationCoordinate2D) coords {
	CustomAnnotation *annotation = [[CustomAnnotation alloc] initWithCoordinate: 
									coords];
	annotation.title = @"标题";
	annotation.subtitle = @"子标题";
	[map addAnnotation:annotation];
}

调用

CLLocationCoordinate2D coords = CLLocationCoordinate2DMake(39.915352,116.397105);
	
	float zoomLevel = 0.02;
	MKCoordinateRegion region = MKCoordinateRegionMake(coords, MKCoordinateSpanMake(zoomLevel, zoomLevel));
	[map setRegion:[map regionThatFits:region] animated:YES];

	
	[self createAnnotationWithCoords:coords];

这样我们就把大头针定位在故宫了

4、定位到当前位置并获取当前经纬度

前面我们已经添加了locationManager，现在在DidViewLoad里直接调用

locationManager = [[CLLocationManager alloc] init];
    locationManager.delegate = self;
    [locationManager startUpdatingLocation];

实现协议方法收到定位成功后的经纬度

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {
    [locationManager stopUpdatingLocation];
    
    NSString *strLat = [NSString stringWithFormat:@"%.4f",newLocation.coordinate.latitude];
    NSString *strLng = [NSString stringWithFormat:@"%.4f",newLocation.coordinate.longitude];
    NSLog(@"Lat: %@  Lng: %@", strLat, strLng);

}

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error {
    NSLog(@"locError:%@", error);

}

运行，允许获取当前位置，打印log

2012-06-28 23:58:32.237 MapDemo[8202:11603] Lat: 39.9011  Lng: 116.3000

如果不允许：打印出错误日志

2012-06-28 23:25:03.109 MapDemo[7531:11603] locError:Error Domain=kCLErrorDomain Code=1 "The operation couldn’t be completed. (kCLErrorDomain error 1.)"

定位后，移动到当前位置：

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation {
    [locationManager stopUpdatingLocation];
    
    NSString *strLat = [NSString stringWithFormat:@"%.4f",newLocation.coordinate.latitude];
    NSString *strLng = [NSString stringWithFormat:@"%.4f",newLocation.coordinate.longitude];
    NSLog(@"Lat: %@  Lng: %@", strLat, strLng);
    
    CLLocationCoordinate2D coords = CLLocationCoordinate2DMake(newLocation.coordinate.latitude,newLocation.coordinate.longitude);
	float zoomLevel = 0.02;
	MKCoordinateRegion region = MKCoordinateRegionMake(coords,MKCoordinateSpanMake(zoomLevel, zoomLevel));
	[map setRegion:[map regionThatFits:region] animated:YES];
}