Question

我尝试计算行进的总距离并将其输出到View Controller，但结果不符合预期。代码如下：

MyCLController.m

- (void)locationManager:(CLLocationManager *)manager
    didUpdateToLocation:(CLLocation *)newLocation
           fromLocation:(CLLocation *)oldLocation
{       
    validLocation = YES;

    if (!newLocation) 
    {
        validLocation = NO;
    }

    if (newLocation.horizontalAccuracy < 0)
    {
        validLocation = NO;
    }

    // Filter out points that are out of order
    NSTimeInterval secondsSinceLastPoint = -[newLocation.timestamp timeIntervalSinceNow];
    if (secondsSinceLastPoint < 0)
    {
        validLocation = NO;
    }

    if (validLocation == YES)
    {
        [self.delegate locationChange:newLocation :oldLocation];
    }

NewWorkoutViewController.m

-(void)locationChange:(CLLocation *)newLocation:(CLLocation *)oldLocation
{       

    CLLocationDistance meters = [newLocation distanceFromLocation:oldLocation];

    currentSpeed = ([newLocation speed] * 3600) / 1000;
    totalDistance = (totalDistance + meters) / 1000;
    totalDistanceMeters =  totalDistanceMeters + meters;
    avgSpeed = totalDistance / counterInt;

    [speedLbl1 setText:[NSString stringWithFormat:@"%.3f", currentSpeed]];
    [distanceLbl1 setText:[NSString stringWithFormat:@"%.3f", totalDistance]];

}

问题在于我的totalDistance，它似乎每次都没有添加它，就像它覆盖它一样，当我在车上测试时我可以看到坐标之间10/20米的值，所以这个表示distanceFromLocation似乎正在工作。

有人有什么想法吗？

问候，斯蒂芬

Answer 1

试试这个：

totalDistance = totalDistance + (meters / 1000);

而不是

totalDistance = (totalDistance + meters) / 1000;

你的方式，每次总距离除以1000，即如果你每次旅行10米：

totalDistance = (0+10) / 1000 = 0.01;
totalDistance = (0.01+10) / 1000 = 0.01001 //!< You expected this to be 0.02!
totalDistance = (0.01001+10) / 1000 = 0.01001001 //!< You expected this to be 0.03!

distanceFromLocation - 未正确计算的总距离

1 个答案: