How to reset state of initial ViewController? - ios

Question

I've 2 ViewController's: VC1 and VC2. In VC1 i've :
#IBAction func cliclOnBtn(_ sender: UIButton) {
CameraController.takePicture()
}
...
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
print("didFinishPickingMediaWithInfo", picker.sourceType)
let _image = (info[UIImagePickerControllerOriginalImage] as! UIImage)
ImageView.image = _image
Images.append(_image)
}
In VC2 i'm passing array of _image, but when i try to back on VC1, photos from camera adding by clicking again. How to reset data? How to make reset of an array of photo, when back button pressed ?

Answer 1

You can implement viewWillAppear in VC1, and then remove all elements of the image Array. This way, when you tap back on VC2, the VC1 will have it's image Array empty.
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
Images.removeAll()
}
Btw, consider renaming your instance variables, lowercasing the initial character, it's a good practice.

Answer 2

Use protocol with delegate for sending data to back
You can update UI or code in delegate function
import UIKit
protocol DestinationViewControllerDelegate {
func updateData(text:String); // you can use Array, Dictonary, Modal as per your requirment
}
class DestinationViewController: UIViewController {
var delegate:FullCalendarViewDelegate! = nil
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
#IBAction func doneButton(sender: AnyObject) {
delegate?.updateData("Got new data")
self.navigationController?.popViewControllerAnimated(true)
}
}
// Sender View Controller
class SenderViewController: UIViewController, DestinationViewControllerDelegate {
#IBOutlet weak var titleLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
#IBAction func NextButton(sender: AnyObject) {
let storyBoard = UIStoryboard(name: "Main", bundle: nil)
let dash:DestinationViewControllerDelegate = storyBoard.instantiateViewControllerWithIdentifier("DestinationViewControllerDelegate") as! DestinationViewControllerDelegate
dash.delegate = self
self.navigationController?.pushViewController(dash, animated: true)
}
func updateData(text:String) {
titleLabel.text = text
}
}