How to retrieve PHAsset from UIImagePickerController - ios

Question

I'm trying to retrieve a PHAsset however PHAsset.fetchAssets(withALAssetURLs:options:) is deprecated from iOS 8 so how can I properly retrieve a PHAsset?

Answer 1

I had the same the issue, first check permissions and request access:
let status = PHPhotoLibrary.authorizationStatus()
if status == .notDetermined {
PHPhotoLibrary.requestAuthorization({status in
})
}
Just hook that up to whatever triggers your UIImagePickerController. The delegate call should now include the PHAsset in the userInfo.
guard let asset = info[UIImagePickerControllerPHAsset] as? PHAsset

Answer 2

Here is my solution:
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
if #available(iOS 11.0, *) {
let asset = info[UIImagePickerControllerPHAsset]
} else {
if let assetURL = info[UIImagePickerControllerReferenceURL] as? URL {
let result = PHAsset.fetchAssets(withALAssetURLs: [assetURL], options: nil)
let asset = result.firstObject
}
}
}

Answer 3

The PHAsset will not appear in the didFinishPickingMediaWithInfo: info result unless the user has authorized, which did not happen for me just by presenting the picker. I added this in the Coordinator init():
let status = PHPhotoLibrary.authorizationStatus()
if status == .notDetermined {
PHPhotoLibrary.requestAuthorization({status in
})
}

Answer 4

I am not sure what you want.
Are you trying to target iOS 8?
This is how I fetch photos and it works in iOS (8.0 and later), macOS (10.11 and later), tvOS (10.0 and later).
Code is commented where it may be confusing
The first functions sets the options to fetch the photos
The second function will actually fetch them
//import the Photos framework
import Photos
//in these arrays I store my images and assets
var images = [UIImage]()
var assets = [PHAsset]()
fileprivate func setPhotoOptions() -> PHFetchOptions{
let fetchOptions = PHFetchOptions()
fetchOptions.fetchLimit = 15
let sortDescriptor = NSSortDescriptor(key: "creationDate", ascending: false)
fetchOptions.sortDescriptors = [sortDescriptor]
return fetchOptions
}
fileprivate func fetchPhotos() {
let allPhotos = PHAsset.fetchAssets(with: .image, options: setPhotoOptions())
DispatchQueue.global(qos: .background).async {
allPhotos.enumerateObjects({ (asset, count, stop) in
let imageManager = PHImageManager.default()
let targetSize = CGSize(width: 200, height: 200)
let options = PHImageRequestOptions()
options.isSynchronous = true
imageManager.requestImage(for: asset, targetSize: targetSize, contentMode: .aspectFit, options: options, resultHandler: { (image, info) in
if let image = image {
self.images.append(image)
self.assets.append(asset)
}
if count == allPhotos.count - 1 {
DispatchQueue.main.async {
//basically, here you can do what you want
//(after you finish retrieving your assets)
//I am reloading my collection view
self.collectionView?.reloadData()
}
}
})
})
}
}
Edit based on OP's clarification
You need to set the delegate UIImagePickerControllerDelegate
then implement the following function
func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : AnyObject]) {
within said method, get the image like this:
var image : UIImage = info[UIImagePickerControllerEditedImage] as! UIImage