Enable User Interaction Enabled for each UIImageView on a Storyboard.

Add TapGestureRecogniser to each UIImageView. Connect each TapGestureRecogniser with IBAction.
@IBAction func tap(_ sender: UITapGestureRecognizer) { currentImageView = sender.view as! UIImageView let picker = UIImagePickerController() picker.delegate = self self.present(picker, animated: true, completion: nil) }
Define variable to store current UIImageView
private var currentImageView: UIImageView? = nil
Handle image selection and assign the image to currentImageView
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) { let image = info[UIImagePickerController.InfoKey.originalImage] currentImageView?.image = image as! UIImage self.dismiss(animated: true, completion: nil) }