如何使iOS获取的地理位置有效

关于CLLocationManager获取地理位置遇到的一些小事；

项目使arc

第一步：获取是否允许定位

-(BOOL)IsLocationServicesEnabled
{
    /**
     * [CLLocationManager locationServicesEnabled] 系统设置允许定位服务是否开启
     * [CLLocationManager authorizationStatus] != kCLAuthorizationStatusDenied  APP是否开启定位服务
     */
    return ([CLLocationManager locationServicesEnabled] && [CLLocationManager authorizationStatus] != kCLAuthorizationStatusDenied);
}

第二步：开始定位，创建全局变量 （个人理解：如果CLLocationManager的属性不是全局的在ARC项目中，出了函数体 局部变量就会被release）

@property (nonatomic, strong) CLLocationManager *userLocation;

-(void)getUserLocationInfomation
{
    if ([self IsLocationServicesEnabled])
    {

        if (!self.userLocation)
        {
            self.userLocation = [[CLLocationManager alloc]init];
        }

        self.userLocation.delegate = self;
        //选择定位的方式为最优的状态
        self.userLocation.desiredAccuracy = kCLLocationAccuracyBest;
        //发生事件的最小距离间隔
        self.userLocation.distanceFilter = kCLDistanceFilterNone;
        [self.userLocation startUpdatingLocation];
    }
}

第三部分：delegate回调

#pragma locationManager delegate

-(void)locationManager:(CLLocationManager *)manager
   didUpdateToLocation:(CLLocation *)newLocation
          fromLocation:(CLLocation *)oldLocation
{
    NSTimeInterval locationAge = -[newLocation.timestamp timeIntervalSinceNow];
    if (locationAge > 180.0) return;
    // 测试该水平精度是否有效
    if (newLocation.horizontalAccuracy < 0) return;
    // 写你的代码 现在拿到的newLocation是有效的   [self.userLocation stopUpdatingLocation];   self.userLocation.delegate = nil;

}

-(void)locationManager:(CLLocationManager *)manager
      didFailWithError:(NSError *)error
{

}