iOS share extension, configurationItems (tableView)

please barer with me that I am completely new to swift and iOS..

I'm trying to make a "team select" on my share extension. Ideally I want to be able to tap the "Team" footer and select multiple teams from a table view, and at last share/post to the selected teams.

I have been following a tutorial from 2016, but I think it is outdated by now unfortunately, and I haven't been able to find one similar that is up to date. (if you know one please link)

I have created a TeamTableViewController.swift (UITableViewController) with a hardcoded teamList which I hope to populate in the share extension.

my UITableViewController file looks like this:

import UIKit

protocol TeamViewProtocol {
  func sendingViewController(viewController: TeamTableViewController, sentItem: String)
}

class TeamTableViewController: UITableViewController {

  var teamList: [String] = ["Team 1", "Team 2", "Team 3", "Team 4", "Team 5"]
  var delegate: TeamViewProtocol?

    override func viewDidLoad() {
        super.viewDidLoad()

        self.clearsSelectionOnViewWillAppear = false
    }

    // MARK: - Table view data source

    override func numberOfSections(in tableView: UITableView) -> Int {
        // #warning Incomplete implementation, return the number of sections
      return 1
    }

    override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        // #warning Incomplete implementation, return the number of rows
        return self.teamList.count
    }

    override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "TeamCell", for: indexPath) 

        cell.textLabel!.text = self.teamList[indexPath.item]

        return cell
    }

}

My ShareViewController filer looks like this:

import UIKit
import Social

class ShareViewController: SLComposeServiceViewController, TeamViewProtocol {

  var item: SLComposeSheetConfigurationItem!
  var teamPickerVC: TeamTableViewController!

    override func isContentValid() -> Bool {
        // Do validation of contentText and/or NSExtensionContext attachments here
        return true
    }

    override func didSelectPost() {
        // This is called after the user selects Post. Do the upload of contentText and/or NSExtensionContext attachments.

        // Inform the host that we're done, so it un-blocks its UI. Note: Alternatively you could call super's -didSelectPost, which will similarly complete the extension context.
        self.extensionContext!.completeRequest(returningItems: [], completionHandler: nil)
    }

  override func configurationItems() -> [Any]! {
    self.item = SLComposeSheetConfigurationItem()

    self.item.title = "Team"
    self.item.value = "None"

    self.item.tapHandler = {
      self.teamPickerVC = TeamTableViewController()
      self.pushConfigurationViewController(self.teamPickerVC)
    }

    return [self.item]
  }

  func sendingViewController(viewController: TeamTableViewController, sentItem: String) {
    self.item.value = sentItem
    self.popConfigurationViewController()
  }

}

When I tap the extension window footer "Team" the entire extension dismisses with no error message. If however, I set the hard coded teamList array to an empty array, then the extensions does not crash/dismiss but instead shows the table view with empty rows.

What am I missing in order for my hard coded teams to show as cell/lines/rows? in the table view?

After a lot of trial and error. I finally found a forum post about the correct implementation of the tableView function that calls with the argument cellForRowAt

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
  var cell = tableView.dequeueReusableCell(withIdentifier: "TeamCell")

  if cell == nil {
    cell = UITableViewCell(style: .default, reuseIdentifier: "TeamCell")
  }

  cell!.textLabel!.text = self.teamList[indexPath.item]
  return cell!
}

This was not easy to debug, and there were no error or exceptions printed.