Save image to file system

Hi! At main.storyboard I have UIImageView and button. I want to save my image witch I took via camera to file system. But when I loading my app again, this image disappeared. Tell me please what I done wrong? This is my code:

import UIKit

class ViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {

@IBAction func useCamera(_ sender: UIButton) {
    let picker = UIImagePickerController()
    picker.sourceType = .camera
    self.present(picker, animated: true, completion: nil)
    picker.delegate = self
@IBOutlet weak var imageView: UIImageView!
override func viewDidLoad() {
    // Do any additional setup after loading the view, typically from a nib.
override func didReceiveMemoryWarning() {
    // Dispose of any resources that can be recreated.
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
    imageView.image = info[UIImagePickerControllerOriginalImage] as? UIImage
    picker.dismiss(animated: true, completion: nil)
    if imageView.image == UIImage(named: "example.jpg") {
        if let data = UIImageJPEGRepresentation(imageView.image!, 0.8) {
            let filename = getDocumentsDirectory().appendingPathComponent("copy.png")
            try? data.write(to: filename)
func getDocumentsDirectory() -> URL {
    let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
    let documentsDirectory = paths[0]
    return documentsDirectory


In your useCamera function, you need to set the picker’s delegate before presenting it.