Question

我有一个应用程序，用户可以拍摄照片或从相机胶卷中选择一个。我需要能够从拍摄图像的位置提取位置（lat＆amp; long）。目前我正在使用位置管理器来获取设备的位置，但这可能会导致位置不准确（即有人可能会拍照但不会发送电子邮件直到他们回家，从而改变位置）

我在这里找到了一个使用“资产库”的解决方案，但是当我从相机胶卷中选择一张照片时，我收到了一个SIGBRAT错误。

有人可以在我的代码中向我显示我出错的地方，或者建议一个简单的方法来获取照片的位置。

以下是我的代码：

- (IBAction)takePhoto
{
    picker1 = [[UIImagePickerController alloc] init];
    picker1.delegate = self;
    [picker1 setSourceType: UIImagePickerControllerSourceTypeCamera];
    [self presentViewController:picker1 animated:YES completion:NULL];
    locationManager.delegate = self;
    locationManager.desiredAccuracy = kCLLocationAccuracyBest;

    [locationManager startUpdatingLocation];


}

- (IBAction)chooseExisting
{
    picker2 = [[UIImagePickerController alloc] init];
    picker2.delegate = self;
    [picker2 setSourceType: UIImagePickerControllerSourceTypePhotoLibrary];
    [self presentViewController:picker2 animated:YES completion:NULL];
    locationManager.delegate = self;
    locationManager.desiredAccuracy = kCLLocationAccuracyBest;

    [locationManager startUpdatingLocation];



}


#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) {
        longditute = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.longitude];
        Latitude = [NSString stringWithFormat:@"%.8f", currentLocation.coordinate.latitude];
    }
    // Stop Location Manager
    [locationManager stopUpdatingLocation];
}



- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{

   image = [info objectForKey:UIImagePickerControllerOriginalImage];
   [imageView setImage:image];
   [self dismissViewControllerAnimated:YES completion:NULL];

    assetsLibrary = [[ALAssetsLibrary alloc] init];
    groups = [NSMutableArray array];

    [assetsLibrary enumerateGroupsWithTypes:ALAssetsGroupSavedPhotos  usingBlock:^(ALAssetsGroup *group, BOOL *stop)
    {
        if (group == nil)
        {
            return;
        }

        [groups addObject:group];

    } failureBlock:^(NSError *error)
    {
        // Possibly, Location Services are disabled for your application or system-wide. You should notify user to turn Location Services on. With Location Services disabled you can't access media library for security reasons.

    }];
    ALAssetsGroup *group = [groups objectAtIndex:0];
    [group enumerateAssetsUsingBlock:^(ALAsset *result, NSUInteger index, BOOL *stop)
     {
         if (result == nil)
         {
             return;
         }

         // Trying to retreive location data from image
         CLLocation *loc = [result valueForProperty:ALAssetPropertyLocation];
         NSLog(loc);
     }];

}

- (void)imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
    [self dismissViewControllerAnimated:YES completion:NULL];
}

Answer 1

你说，或者你可以用一种简单的方法来获取数据。

所以我可以指出两个处理这个问题的帖子。您首先需要确保用户已授予应用程序权限，以允许位置服务获取应用程序所需的详细信息。

Nice answer given over here更详细地介绍了包括代码和其他重要答案given here在内的要点首先检查第一个，然后检查第二个链接。

提取图像位置数据

1 个答案: