无法通过flutter应用程序打开浏览器URL

dependencies:
  flutter_inappwebview: ^5.3.2

import 'package:flutter_inappwebview/flutter_inappwebview.dart';

InAppWebView webView;

@override
void initState() {
  super.initState();
  webView = InAppWebView(
    initialUrlRequest: URLRequest(url: Uri.parse('https://example.com')),
  );
}

@override
Widget build(BuildContext context) {
  return Scaffold(
    appBar: AppBar(
      title: Text('WebView'),
    ),
    body: Container(
      child: webView,
    ),
  );
}

ElevatedButton(
  onPressed: () {
    webView.loadUrlRequest(
      URLRequest(url: Uri.parse('https://example.com')),
    );
  },
  child: Text('打开URL'),
),