如何在flutter的webview中显示pdf

import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';

class PDFWebView extends StatefulWidget {
  @override
  _PDFWebViewState createState() => _PDFWebViewState();
}

class _PDFWebViewState extends State<PDFWebView> {
  final String pdfUrl = 'https://example.com/sample.pdf'; // 替换为实际的PDF文件URL

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('PDF WebView'),
      ),
      body: WebView(
        initialUrl: 'about:blank',
        onWebViewCreated: (WebViewController controller) {
          _loadPDF(controller);
        },
      ),
    );
  }

  void _loadPDF(WebViewController controller) async {
    String pdfViewerScript = '''
      window.open('$pdfUrl', '_blank');
    ''';

    await controller.evaluateJavascript(pdfViewerScript);
  }
}