How can I save multiple images which are picked from the UIPickerController? - swift

Question

All the images which I'm uploading in the app (with the UIImagePickerController) are showing in the app but when I'm closing the app the images disappear. I used UserDefaults for one image (without the UICollectionView) and the code worked (see the code) but when i used the UICollectionView, the code does not work anymore. It would be nice if anyone can help me or give me some tips!
import UIKit
class wardrobeViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate, UICollectionViewDelegate, UICollectionViewDataSource {
#IBOutlet weak var allImagesCollection: UICollectionView!
var collectionViewClass = CollectionViewCell()
var theUploadedImg = UIImageView()
let userDefault = UserDefaults.standard
override func viewDidLoad() {
super.viewDidLoad()
allImagesCollection.delegate = self
allImagesCollection.dataSource = self
collectionViewClass.newImage = theUploadedImg
let imageData = userDefault.object(forKey: "thePickedImage") as? NSData
if let imageData = imageData {
let image = UIImage(data: imageData as Data)
theUploadedImg.image = image
}
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
#IBAction func chooseImage(_ sender: Any) {
let imagePickerController = UIImagePickerController()
imagePickerController.delegate = self
let actionSheet = UIAlertController(title: "", message: "Choose an image from", preferredStyle: .actionSheet)
actionSheet.addAction(UIAlertAction(title: "Camera", style: .default, handler: { (action: UIAlertAction) in
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.camera) {
imagePickerController.sourceType = UIImagePickerControllerSourceType.camera
imagePickerController.allowsEditing = false
self.present(imagePickerController, animated: true, completion: nil)
}
}))
actionSheet.addAction(UIAlertAction(title: "Photo Library", style: .default, handler: { (action: UIAlertAction) in
if UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.photoLibrary) {
imagePickerController.sourceType = UIImagePickerControllerSourceType.photoLibrary
imagePickerController.allowsEditing = false
self.present(imagePickerController, animated: true, completion: nil)
}
}))
actionSheet.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
self.present(actionSheet, animated: true, completion: nil)
}
var newPickedImage = [UIImage]()
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
if let pickedImage = info[UIImagePickerControllerOriginalImage] as? UIImage {
theUploadedImg.contentMode = .scaleToFill
theUploadedImg.image = pickedImage
newPickedImage.append(pickedImage)
let pickedImageData = UIImagePNGRepresentation(pickedImage)
userDefault.set(pickedImageData, forKey: "thePickedImage")
}
picker.dismiss(animated: true, completion: nil)
allImagesCollection.reloadData()
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return newPickedImage.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! CollectionViewCell
cell.newImage.image = newPickedImage[indexPath.item]
cell.layer.borderColor = UIColor.lightGray.cgColor
cell.layer.borderWidth = 0.5
return cell
}
let cellsPerRow = 3
override func viewWillLayoutSubviews() {
guard let collectionView = allImagesCollection, let flowLayout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout else { return }
let marginsAndInsets = flowLayout.sectionInset.left + flowLayout.sectionInset.right + collectionView.safeAreaInsets.left + collectionView.safeAreaInsets.right + flowLayout.minimumInteritemSpacing * CGFloat(cellsPerRow - 1)
let itemWidth = ((collectionView.bounds.size.width - marginsAndInsets) / CGFloat(cellsPerRow)).rounded(.down)
flowLayout.itemSize = CGSize(width: itemWidth, height: itemWidth)
}
}

Answer 1

You are saving only 1 image to UserDefaults. In order to persist these images, you have to save all of them, not just override 1 image. Also, on application start you have to fetch all of the images and reload UICollectionView with them.
One more tip, do not save images to UserDefaults, use FileManager.