how to modify an array from another class - ios

Question

Im making to do list-app which consist of 2 View Controllers
one with table view hold an array and display it and second one with a textField, a button function to append the text field's text to the array
to display the new appended string it in the first view controller
heres my code:
class ViewController: UIViewController,UITableViewDataSource,UITableViewDelegate {
#IBOutlet weak var tableView: UITableView!
var exmpArray = ["DDDD","rrr","TTT"]
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
#IBAction func addBtnBar(_ sender: Any) {
performSegue(withIdentifier: "showMe", sender: nil)
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return exmpArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell")
cell?.textLabel?.text = exmpArray[indexPath.row]
return cell!
}}
and the second one is:
class SecondViewController: UIViewController {
#IBOutlet weak var myTextField: UITextField!
var realAry:[String] = []
override func viewDidLoad() {
super.viewDidLoad()
}
let myObj = ViewController()
#IBAction func addBtn(_ sender: Any) {
myObj.exmpArray.append(myTextField.text!)
print(myObj.exmpArray)
}
after appending the new words it doesn't display in the first controller

Answer 1

One problem is this line:
let myObj = ViewController()
That creates a new instance of ViewController that has nothing to do with the view controller that called you. Get rid of that line. It's wrong.
You need to set up a delegate property in SecondViewController that points back to ViewController, define a protocol for that delegate to conform to, and use that protocol so that SecondViewController can notify it's delegate when the array changes.
In ViewController, add a prepareForSegue() function that takes the destination view controller, casts it to type SecondViewController, and sets SecondViewController's delegate to self.

Answer 2

Both arrays are different you are just copying first VC array to 2nd VC array. Array is value type in swift. Instead of creating 2 arrays make 1st VC array as static.
static var exmpArray = ["DDDD","rrr","TTT"]
Now you can use & update this in all VC by calling like below
FirstVC.exmpArray