I'm using WKWebView to load content. That part of the code works fine. Now I want to add a toolbar: went to storyboard, added toolbar, added button in the toolbar. Hit run just to see the toolbar in the simulator and nothing!! Code is below: //  Created by Matthew on 8/31/21. import UIKit import WebKit class ViewController: UIViewController, WKUIDelegate, WKNavigationDelegate {     @IBOutlet weak var webView: WKWebView!     override func viewDidLoad() {         super.viewDidLoad()         //start code         let webView = WKWebView()         webView.uiDelegate = self         webView.navigationDelegate = self                  let htmlURL = Bundle.main.url(forResource: "index", withExtension: "html", subdirectory: "FILES")!         webView.loadFileURL(htmlURL, allowingReadAccessTo: htmlURL.deletingLastPathComponent())         view = webView     }     //Can't get toolbar to show on simulator. Can not test print button     @IBOutlet weak var Toolbar: UIToolbar!     @IBAction func BBI(_ sender: Any) { }         @IBAction func PrintPDF(_ sender: Any) {         let printController = UIPrintInteractionController.shared         let printInfo = UIPrintInfo(dictionary:nil)         printInfo.outputType = UIPrintInfo.OutputType.general         printInfo.jobName = (webView.url?.absoluteString)!         printInfo.duplex = UIPrintInfo.Duplex.none         printInfo.orientation = UIPrintInfo.Orientation.portrait         printController.printPageRenderer = nil         printController.printingItems = nil         printController.printingItem = webView.url!         printController.printInfo = printInfo         printController.showsNumberOfCopies = true         //printController.printFormatter = webView.viewPrintFormatter()         //printController.presentFromBarButtonItem(PrintPDF, animated: true, completionHandler: nil)         printController.present(animated: true, completionHandler: nil)     }     override func didReceiveMemoryWarning() {         super.didReceiveMemoryWarning()         // dispose of any resources that can be recreated     } }

I'm getting a question mark near my reference folder. Any idea why this would be happening?? The app builds and then spits out this error "Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value" by bundle.main.url import UIKit import WebKit class ViewController: UIViewController {     @IBOutlet weak var loadhtml: WKWebView!     override func viewDidLoad() {         super.viewDidLoad()         let webView = WKWebView()         let htmlURL = Bundle.main.url(forResource: "index", withExtension: "html", subdirectory: "FILES")!         webView.loadFileURL(htmlURL, allowingReadAccessTo: htmlURL.deletingLastPathComponent())         view = webView     }     override func didReceiveMemoryWarning() {         super.didReceiveMemoryWarning()         // dispose of any resources that can be recreated     } }