无法将JS注入Swift/ Cocoa /NextStep中的WKWebView /将WKWebView中网页上的用户选择推送到Swift /Cocoa

let configuration = WKWebViewConfiguration()
configuration.preferences.javaScriptEnabled = true
let webView = WKWebView(frame: .zero, configuration: configuration)

class ViewController: UIViewController, WKScriptMessageHandler {
    var webView: WKWebView!

    override func viewDidLoad() {
        super.viewDidLoad()
        
        let configuration = WKWebViewConfiguration()
        let userContentController = WKUserContentController()
        userContentController.add(self, name: "callbackHandler")
        configuration.userContentController = userContentController
        
        webView = WKWebView(frame: self.view.frame, configuration: configuration)
        self.view.addSubview(webView)
        
        // 加载网页
        if let url = URL(string: "https://example.com") {
            let request = URLRequest(url: url)
            webView.load(request)
        }
    }

    func userContentController(_ userContentController: WKUserContentController, didReceive message: WKScriptMessage) {
        if message.name == "callbackHandler", let messageBody = message.body as? String {
            print("Received message from JS: \(messageBody)")
            // 处理从JS传递过来的数据
        }
    }
}

window.webkit.messageHandlers.callbackHandler.postMessage("Hello from JavaScript");

// 示例：简单的JavaScript函数
function greet(name) {
    return "Hello, " + name + "!";
}