在flutter中使用showDialog会抛出错误-“‘!_debugLocked'：不是真的。”

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('Dialog Example')),
        body: Center(
          child: ElevatedButton(
            onPressed: () {
              showDialog(
                context: context,
                builder: (BuildContext context) {
                  return AlertDialog(
                    title: Text('Example Dialog'),
                    content: Text('This is an example dialog.'),
                    actions: <Widget>[
                      TextButton(
                        child: Text('OK'),
                        onPressed: () {
                          Navigator.of(context).pop();
                        },
                      ),
                    ],
                  );
                },
              );
            },
            child: Text('Show Dialog'),
          ),
        ),
      ),
    );
  }
}