在颤振中使用导航器后出现黑屏

Question

这是使用Navigator Route的三个文件的代码段。 路由到下一页时，输出只是空白屏幕。

main.dart

我已在此处初始化路由名称

import 'package:flutter/material.dart';
import './homepage.dart';
import './itemdetails.dart';

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(............
    .................................
    .................................
        routes: {
        '/': (ctx) => HomePage(),
        DetailsScreen.routname: (ctx) => DetailsScreen()
      },
    );
  }
}

homepage.dart

..........................
..............................
..............................
class CardDesign extends StatelessWidget {
  void itemDetails(BuildContext context) {
    Navigator.of(context).pushNamed(
      DetailsScreen.routname,
    );
  }

  Widget build(BuildContext context) {
    return InkWell(
      onTap: () => itemDetails(context),
      child: Card(
        shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.all(Radius.circular(20))),
        elevation: 3,..........
.....................
.................

itemdetails.dart

最后一页显示空白屏幕

import 'package:flutter/material.dart';

class DetailsScreen extends StatelessWidget {
  static const String routname = '/DetailsScreen';

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Text("hlooo"),
      ),
    );
  }
}