地图相关

iOS上使用地图比Android要方便，只需要新建一个MKMapView,addSubView即可。这次要实现的效果如下：

有标注（大头针），定位，地图。

1、添加地图

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

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#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

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- (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

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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：

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#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

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#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

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

调用

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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

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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

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- (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

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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

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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：

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- (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];
}