CLLocationManager 位置定位

转：http://my.oschina.net/chengliqun/blog/147870

 

最近由于项目需要，需要使用LBS相关技术，但网上搜索了一圈，文章不是很多，故自己就从头整理记录些吧，以供日后温习参考；

    下面就开始吧，首先，如标题，先定位吧。

    第一步，新建一个singleView的空白工程,如果新建，这里不做赘述了。

    第二步：因为地图开发相关的framework：MapKit.framework、CoreLocation.framework， 至于如何添加，一般的ios相关博客都是有介绍。

   在主界面的控制器 ViewController.h 文件中，我们啥也不做，.m文件中，我们需声明一个 CLLocationManager* locationManager的属性，我们让其实现CLLocationManagerDelegate的协议，并覆写其更新位置的方法，如下：

 

//
//  ViewController.m
//  LBS_001_CLLocationManager
//
//  Created by liqun on 13-7-17.
//  Copyright (c) 2013年 Block Cheng. All rights reserved.
//

#import "ViewController.h"
#import <CoreLocation/CoreLocation.h>
@interface ViewController ()<CLLocationManagerDelegate>{
    
}

@property (nonatomic,retain)CLLocationManager* locationManager;

@end

@implementation ViewController

-(id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil

{
    if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
        NSLog(@"nibName:  %@   bundle: %@",nibBundleOrNil,nibBundleOrNil);
        _locationManager = [[CLLocationManager alloc] init];
        
    }
    
    return  self;
}

- (void)dealloc
{
    self.locationManager = nil;
    [super dealloc];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    //delegate
    self.locationManager.delegate = self;
    //The desired location accuracy.
    self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
    //Specifies the minimum update distance in meters.

    self.locationManager.distanceFilter = kCLDistanceFilterNone;

    self.locationManager.purpose = @"To provide functionality based on user's current location.";

    [self.locationManager startUpdatingLocation];
}

- (void)locationManager:(CLLocationManager *)manager didChangeAuthorizationStatus:(CLAuthorizationStatus)status {
    NSLog(@"didChangeAuthorizationStatus---%u",status);
}

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

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{
    UIAlertView* av = [[UIAlertView alloc] initWithTitle:@"update" message:[NSString stringWithFormat:@"didUpdateToLocation:  newLocation: %@  old:%@",newLocation,oldLocation] delegate:nil cancelButtonTitle:@"cancel" otherButtonTitles:@"ok", nil];
    [av show];
    [av release];
}

- (void)didReceiveMemoryWarning{
    [super didReceiveMemoryWarning];
}

@end

 

程序启动后，系统会进行授权询问，如下：

点击好同意后，便能得到相应的位置信息，在代理的回调方法中，弹出信息

- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation

效果如下：

其实，在给出获取位置信息前，我们应该给出用户以提示的，见上效果图：

  self.locationManager.purpose = @"To provide functionality based on user's current location."; 

 

如果用户拒绝后，我们应该做相应的提示处理，在代理方法中也需做相应的处理。

还有一种开去位置服务的方法，先检查位置服务是否可用，再获取：

 

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");
}