iphone - CLLocation 生成奇怪的错误

Question

我的 CLLocation 遇到问题。
我想知道两个坐标之间的距离，以便将其显示在 tableView 中位置标题旁边:

    static NSString *CellIdentifier = @"Cell";

 UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
 if (cell == nil) {
  cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier] autorelease];
 }

 // The first CLLocation based on the coordinates my MKMapView gives me.
 CLLocation *userLocation = [[CLLocation alloc] initWithLatitude:mapView.userLocation.coordinate.latitude longitude:mapView.userLocation.coordinate.longitude];

    // The second CLLocation based on the coordinates which are saved as a NSNumber in my own object
 CLLocation *locationForIndex = [[CLLocation alloc] initWithLatitude:[[[locations objectAtIndex:indexPath.row] latitude] doubleValue] longitude:[[[locations objectAtIndex:indexPath.row] longitude] doubleValue]];
 CLLocationDistance distance = [userLocation distanceFromLocation:locationForIndex];

 cell.textLabel.text = [[locations objectAtIndex:indexPath.row] title];
 cell.detailTextLabel.text = [[NSString alloc] initWithString:[NSString stringWithFormat:@"%d", distance]];

 return cell;

现在我得到的错误是:

有人有可行的解决方案吗？

谢谢!!

Answer 1

您是否已将 Core Location 框架与 MapKit 一起包含在内？