UIWebView迁移后WKWebView中显示的链接不起作用

let webView = WKWebView(frame: CGRect(x: 0, y: 0, width: 320, height: 480))
webView.configuration.preferences.javaScriptEnabled = true

let webView = WKWebView(frame: CGRect(x: 0, y: 0, width: 320, height: 480))
let preferences = WKPreferences()
preferences.setValue(true, forKey: "allowFileAccessFromFileURLs")
webView.configuration.preferences = preferences

class MyNavigationDelegate: NSObject, WKNavigationDelegate {
    func webView(_ webView: WKWebView, decidePolicyFor navigationAction: WKNavigationAction, decisionHandler: @escaping (WKNavigationActionPolicy) -> Void) {
        if let url = navigationAction.request.url {
            // 判断是否是重定向链接
            if url.absoluteString.contains("redirect") {
                // 允许跳转
                decisionHandler(.allow)
                return
            }
        }
        
        // 阻止跳转
        decisionHandler(.cancel)
    }
}

let webView = WKWebView(frame: CGRect(x: 0, y: 0, width: 320, height: 480))
let navigationDelegate = MyNavigationDelegate()
webView.navigationDelegate = navigationDelegate