pragma mark - CLLocationManagerDelegate

Question

我正在使用CLLocationDistance来获取两点之间的距离，但是当我在其中传递当前位置时出现错误。

CLLocation *current = [[CLLocation alloc] initWithLatitude:startLocation.coordinate.latitude longitude:startLocation.coordinate.longitude];
CLLocation *itemLoc = [[CLLocation alloc] initWithLatitude:[[[getName objectAtIndex:indexPath.row] objectForKey:@"lat"] doubleValue] longitude:[[[getName objectAtIndex:indexPath.row] objectForKey:@"lon"] doubleValue]];

//Here the current location gives me an error "Initializing cllocation with an expression incompatible format"
CLLocationDistance *itemDist = [itemLoc distanceFromLocation:current];
NSLog(@"Distance: %@", itemDist);

Answer 1

swift 2.0是否采用以下方式：

let userLocation:CLLocation = CLLocation(latitude: 11.11, longitude: 22.22)
let priceLocation:CLLocation = CLLocation(latitude: 33.33, longitude: 44.44)
let meters:CLLocationDistance = userLocation.distanceFromLocation(priceLocation)

Answer 2

您获得的错误实际上是：

使用不兼容类型'CLLocationDistance'（又名'double'）的表达式初始化'CLLocationDistance *'（又名'double *'）

它的含义是你正在将itemDist（你已宣布为CLLocationDistance *）初始化为返回CLLocationDistance的东西（注意没有星号）。

CLLocationDistance不是对象它只是一种原始类型（具体为double - 请参阅Core Location Data Types Reference）。

因此，不要将itemDist声明为指针到CLLocationDistance，而是将其声明为CLLocationDistance（无星号）：

CLLocationDistance itemDist = [itemLoc distanceFromLocation:current];

您还需要更新NSLog以期望 double 而不是对象，否则它将在运行时崩溃：

NSLog(@"Distance: %f", itemDist);

Answer 3

以下代码适合您在视图加载

//************************** GEtting USer's latitude/ Longitude ********************




  self.locationManager = [[CLLocationManager alloc] init];
        self.locationManager.delegate = self;
        [self.locationManager startUpdatingLocation];
//************************** GEtting USer's latitude/ Longitude ********************

pragma mark - CLLocationManagerDelegate

- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
    NSLog(@"didFailWithError: %@", error);
    UIAlertView *errorAlert = [[UIAlertView alloc]
                               initWithTitle:@"Error" message:@"Failed to Get Your Location" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
    [errorAlert show];
}
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
    NSLog(@"didUpdateToLocation: %@", newLocation);
    CLLocation *currentLocation = newLocation;
    if (currentLocation != nil) {        
        CLLocation *locA = [[CLLocation alloc] initWithLatitude:currentLocation.coordinate.longitude longitude:currentLocation.coordinate.latitude];
        CLLocation *locB = [[CLLocation alloc] initWithLatitude:11.111111111111111 longitude:11.1111111111111111]; 
        User_Vanue_Distance = [locA distanceFromLocation:locB];
        NSLog(@"THIS IS THE DISTANCE BT TWO POINTS +++++++++++++++++++++%f",User_Vanue_Distance);  
    }
}

你需要在info.plist中放入以下密钥，在ios 8中访问我们需要放在info.plist中的密钥下面的位置 1. NSLocationWhenInUseUsageDescription : Location required 2. NSLocationAlwaysUsageDescription Needed : Location Needed

这对您有用，但您需要添加的一件事是添加对ios8的检查。否则这将在ios 7上崩溃

// Check for iOS 8. Without this guard the code will crash with "unknown selector" on iOS 7.


  if ([self.locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)]) {
        [self.locationManager requestWhenInUseAuthorization];
    }

希望这对你有用。：）

Answer 4

从两个不同的Lat＆amp;长

let userLocation:CLLocation = CLLocation(latitude: 23.0320, longitude: 72.5250) let priceLocation:CLLocation = CLLocation(latitude: 23.0283, longitude: 72.5067) let distance = String(format: "%.2f km", userLocation.distanceFromLocation(priceLocation)/1000) print("Distance is KM is:: \(distance)")

使用CLLocation计算两个坐标之间的距离

4 个答案:

pragma mark - CLLocationManagerDelegate