Question

我正在研究这种行走/跑步应用程序，它以米为单位计算距离并记录纬度以供进一步使用。现在，当我计算距离时，每次都会得到不正确的距离。我将它与其他正在运行的应用程序进行了比较，它们通常显示的距离与我的距离不同。

以下是我正在使用的代码：

#define kDesiredAccuracy 5.0f

self.locationManager = [[CLLocationManager alloc] init];
self.locationManager.desiredAccuracy = kCLLocationAccuracyBestForNavigation;
self.locationManager.distanceFilter = kDesiredAccuracy;
_routes = [[NSMutableArray alloc] init];
lastKnownLocation = nil;

-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
    // return if accuracy is less than 0 or is greater than desired accuracy.
    if (newLocation.horizontalAccuracy < 0)
    {
        return;
    }
    if(newLocation.horizontalAccuracy > kDesiredAccuracy)
    {
        return;
    }

    NSTimeInterval locationAge = -[newLocation.timestamp timeIntervalSinceNow];
    CLLocationSpeed speed = [newLocation speed];
    // return if stale data or user is not moving
    if (locationAge > 5.0 || speed <= 0) return;

    //return if first location is found
    if(lastKnownLocation == nil)
    {
        lastKnownLocation = newLocation;
        return;
    }

    CLLocationDistance distance = [newLocation distanceFromLocation:(self.pramDistance > 0)?lastKnownLocation:oldLocation];
    if(distance > 0)
    {
        // save distance for future use
        NSMutableDictionary *dict=[[NSMutableDictionary alloc] init];
        [dict setObject:[NSString stringWithFormat:@"%g", newLocation.coordinate.latitude] forKey:@"latitude"];
        [dict setObject:[NSString stringWithFormat:@"%g", newLocation.coordinate.longitude] forKey:@"longtitude"];
        [dict setObject:[NSString stringWithFormat:@"%f",distance]   forKey:@"distance"];
        [_routes addObject:dict];
        // add distance to total distance.
        self.pramDistance += distance;
    }

}

一旦用户完成步行/跑步，我在地图视图上绘制步行/跑步的路线。为此，我只需使用所有记录的位置在MKMapView上绘制一条ploy线。

地图视图显示路线的Z字形线，距离始终不正确。请建议我在哪里做错了，我应该修改什么才能让它正常工作？

以下是比较（左边是其他应用，右边是我的）： Comparison of other app and my app

Answer 1

试试这个，

导入CLLocationManagerDelegate，

 CLLocation *currentLocation = self.currentLocation;
       float distanceMile = [currentLocation distanceFromLocation:[[CLLocation alloc] initWithLatitude:latitude longitude:longitude]]/1609.34;

    -(void)postCurrentLocationOfDevice
    {

        self.locationManager = [[CLLocationManager alloc] init];
        self.locationManager.distanceFilter = kCLDistanceFilterNone;
        self.locationManager.desiredAccuracy = kCLLocationAccuracyBest;
        [self.locationManager startUpdatingLocation];
        self.locationManager.delegate = self;

    }
    -(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
    {
       self.currentLocation = [locations objectAtIndex:0];
        [self.locationManager stopUpdatingLocation];

    }

    -(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
    {
        self.currentLocation = newLocation;
        [self.locationManager stopUpdatingLocation];
    }

Answer 2

虽然我没有得到很多帮助，但我在这个问题上找到了一些帮助和想法：Corelocation incorrect distances

我为解决这个问题所做的是：

我将最近的5个地点存储在一个数组中。
一旦5个项目存储在数组中，我就检查了最近的位置。
在到达最近的位置后，我计算了最后一个最佳位置与最后一个最佳位置存储的新位置之间的距离。

P.S。：我的代码很乱，命名约定不是通用的，这就是为什么我不在这里发布我的代码。

在我的步行/跑步应用程序中找到不正确的距离和路线

2 个答案: