imagePickerController.swift

extension ViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey: Any]) {
        picker.dismiss(animated: true)
        
        guard let uiImage = info[UIImagePickerController.InfoKey.originalImage] as? UIImage else {
            fatalError("Error!")
        }
        imageView.image = uiImage
        createVisionRequest(image: uiImage)
    }
    
    private func presentPhotoPicker(sourceType: UIImagePickerController.SourceType) {
        let picker = UIImagePickerController()
        picker.delegate = self
        picker.sourceType = sourceType
        present(picker, animated: true)
    }
}