UI elements are nil in share extension swift

Question

I've been developing a share extension for my iOS app with a custom view controller. The custom view controller has an ImageView, a label and a textBox. I want to get the url from the webpage where the user tries to share with my app and set it as the text of the label. But when I try to get access to the label, it is nil. I've been trying this operation in diferente lifecycle methods, as viewDidLoad(), viewWillLoad() and finally I use viewDidAppear() but the result it's the same. The elements are properly connected in the storyboard to the Viewcontroller:

Here it's my ViewController code:

import UIKit
import Social

class ShareViewController: UIViewController {

   @IBOutlet var ScreenCapture: UIImageView!
   @IBOutlet var articleTitle: UITextField!
   @IBOutlet var urlLabel: UILabel!




   override func viewDidLoad() {
       super.viewDidLoad()

   }

   override func viewDidAppear(_ animated: Bool) {
       super.viewDidAppear(animated)
       if let item = extensionContext?.inputItems.first as?    NSExtensionItem {
           if let attachments = item.attachments {
               for attachment: NSItemProvider in attachments {
                   if attachment.hasItemConformingToTypeIdentifier("public.url") {
                    attachment.loadItem(forTypeIdentifier: "public.url", options: nil, completionHandler: { (url, error) in
                        if let shareURL = url as? URL {
                            self.urlLabel.text = shareURL.absoluteString
                        }
                    })
                }
            }
        }
    }
   }


   @IBAction func cancelShare(_ sender: Any) {
          self.extensionContext!.completeRequest(returningItems: [], completionHandler: nil)
   }
   @IBAction func doneShare(_ sender: Any) {
       //TODO: Insert into CoreData
          self.extensionContext!.completeRequest(returningItems: [], completionHandler: nil)
   }
}

I put a breakpoint in the self.urlLabel.text = shareURL.absoluteStringline and here it's the debugger information:

EDIT: Finally I solved my issue, I must call loadViewIfNeeded():

override func loadViewIfNeeded() {
    super.loadViewIfNeeded()
    let image = makeScreenShoot(withView: view)
    if let item = extensionContext?.inputItems.first as? NSExtensionItem {
        if let attachments = item.attachments {
            for attachment: NSItemProvider in attachments {
                if attachment.hasItemConformingToTypeIdentifier("public.url") {
                    attachment.loadItem(forTypeIdentifier: "public.url", options: nil, completionHandler: { (url, error) in
                        if let shareURL = url as? URL {
                            self.urlLabel.text = shareURL.absoluteString
                        }
                    })
                }
            }
        }
    }
    ScreenCapture.image = image
}