title: why the viewDidAppear is not calling?
body: <pre><code>import UIKit
  
  import SwiftyDropbox
  
  class NotesViewController: UIViewController, UITableViewDataSource, UITableViewDelegate, NotesviewDelegate {
  
  var userText:[String] = []
  
  @IBOutlet weak var tableView: UITableView!
  
  override func viewDidLoad() {
      super.viewDidLoad()
  
      print("View Did Load Notes view controller")
  }
  
  override func viewWillAppear(_ animated: Bool) {
      print("View will Appear")
      self.tabBarController?.navigationItem.title = "Notes"
  
      let sendButton = UIBarButtonItem(title: "New", style: .plain, target: self, action: #selector(goToNoteEditorViewController))
  
      self.tabBarController?.navigationItem.rightBarButtonItem = sendButton
      self.automaticallyAdjustsScrollViewInsets = false
  }
  
  override func viewDidAppear(_ animated: Bool) {
  
      print("View Did appear Notes view controller")
      didDoneButtonPressed()
  
  }
  
  func goToNoteEditorViewController() {
  
      let storyboard = UIStoryboard(name: "Main", bundle: nil)
  
      guard let vc = storyboard.instantiateViewController(withIdentifier:"NoteEditorViewID") as? NoteEditorViewController else{
          return
      }
      vc.delegate = self
      self.navigationController?.present(vc, animated: true, completion: nil)
  
  }
  
  
  public func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -&gt; Int{
  
      return userText.count
  }
  
  
  public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -&gt; UITableViewCell{
  
      let cell = UITableViewCell(style: UITableViewCellStyle.default, reuseIdentifier: "cell")
      cell.textLabel?.text = userText[indexPath.row]
      print("The cell is \(cell)")
      return (cell)
  }
  
  public func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath){
  
      let controller = UIStoryboard(name: "Main", bundle: nil)
  
      guard let viewController = controller.instantiateViewController(withIdentifier:"TextDisplayID") as? TextDisplayViewController else{
          return
      }
  
      let indexPath = tableView.indexPathForSelectedRow
  
      let currentCell = tableView.cellForRow(at: indexPath!)!
  
      let text = currentCell.textLabel!.text ?? ""
      print(currentCell.textLabel!.text ?? "")
  
      viewController.textTitle = text
      navigationController?.pushViewController(viewController, animated: true)
  }
  
  func didDoneButtonPressed() {
  
      let userDefaults = UserDefaults()
  
      if let dictionary = userDefaults.dictionary(forKey: "UserNotes"){
          if let dictionaryTexts = dictionary as? [String : String] {
              userText = [String](dictionaryTexts.keys)
  
              print("array values: \(userText)")
              self.tableView.reloadData()
          }
      }
  }
  }
  </code></pre>
  
  <p>In the above program the viewDidAppear is not call at the time of execution.Can anyone explain why this happen? </p>