我正在使用UIImagePickerController用相机拍照，也可以从SavedPhotosAlbum库中获取照片。用户拍照后，我将其保存在SavedPhotosAlbum中，并调用以下方法：
override func image(image: UIImage, didFinishSavingWithError: NSErrorPointer, contextInfo:UnsafePointer<Void>) {
if (didFinishSavingWithError != nil) {
print("Error saving photo: \(didFinishSavingWithError)")
} else {
let photoToSend = CompressAndSendPhoto(image: image)
photoToSend.uploadImageRequest()
print("Successfully saved photo, will make request to update asset metadata")
let fetchOptions = PHFetchOptions()
fetchOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: true)]
let fetchResult = PHAsset.fetchAssetsWithMediaType(PHAssetMediaType.Image, options: fetchOptions)
let lastImageAsset = fetchResult.lastObject as! PHAsset
let coordinate = CLLocationCoordinate2DMake(self.coordinate1, self.coordinate2)
let nowDate = NSDate()
let myLocation = CLLocation(coordinate: coordinate, altitude: 0.0, horizontalAccuracy: 1.0, verticalAccuracy: 1.0, timestamp: nowDate)
PHPhotoLibrary.sharedPhotoLibrary().performChanges({
let assetChangeRequest = PHAssetChangeRequest(forAsset: lastImageAsset)
assetChangeRequest.location = myLocation
}, completionHandler: {
(success:Bool, error:NSError?) -> Void in
if (success) {
print("Succesfully saved metadata to asset")
print("location metadata = \(myLocation)")
} else {
print("Failed to save metadata to asset with error: \(error!)")
}
});
}
}
它工作正常，用户当前位置正被添加到照片资产。 问题是我从SavedPhotosAlbum选择照片时无法获得此值。我搜索了许多选项，但没有一个可行。我怎么能用下面的方法呢？
func imagePickerController(
picker: UIImagePickerController,
didFinishPickingMediaWithInfo info: [String : AnyObject])
{
let chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
if picker.sourceType == UIImagePickerControllerSourceType.SavedPhotosAlbum {
}
dismissViewControllerAnimated(true, completion: nil)
}
此外，我想在照片资产中添加更多“字段”，不仅仅是默认位置之一，如何添加自定义NSDictionary值？