ViewController.swift

import UIKit
import ReCaptcha


class ViewController: UIViewController {
     
     private struct Constants {
          static let webViewTag = 123
          static let testLabelTag = 321
     }
     
     private var recaptcha: ReCaptcha!
     private var locale: Locale = Locale(identifier: "ru_RU")
     private var endpoint = ReCaptcha.Endpoint.default
     
     
     override func viewDidLoad() {
          super.viewDidLoad()
          
          
          do {
               try recaptcha = ReCaptcha(apiKey: "6LfKP3IUAAAAAK6kaATeyQNqOfhowRy8UyVP4qYY", baseURL: URL(string: "https://www.google.com/recaptcha/api.js"), endpoint: endpoint, locale: locale)
          } catch {
               print(error)
          }
          
          recaptcha.configureWebView { [weak self] webview in
               webview.frame = self?.view.bounds ?? CGRect.zero
               webview.tag = Constants.webViewTag
               webview.backgroundColor = UIColor.red
               self?.view.viewWithTag(Constants.testLabelTag)?.removeFromSuperview()
               let label = UILabel(frame: CGRect(x: 0, y: 0, width: 1, height: 1))
               label.tag = Constants.testLabelTag
               label.accessibilityLabel = "webview"

               self?.view.addSubview(label)
               print("hello")
          }
     }
     
     override func didReceiveMemoryWarning() {
          super.didReceiveMemoryWarning()
          // Dispose of any resources that can be recreated.
     }
     
     @IBAction func printHello(sender: AnyObject) {
          let res = recaptcha.validate(on: view) { [weak self] (result: ReCaptchaResult) in
               let a = try? result.dematerialize()
               print("grecaptcha result is", a)
          }
     }
     
}