flutter - Flutter 问题：将参数作为命名参数传递给 Widget 构造函数

Question

颤振问题。我正在尝试将参数作为命名参数传递给 Widget 构造函数，但出现错误：未定义命名参数“uri”。下面是我定义类的代码，后面是我实例化 Widget 的代码。我被困住了。任何帮助深表感谢！

//Code defining Widget

class VideoPlayerApp extends StatelessWidget {
  VideoPlayerApp({this.uri});
  final Text uri;
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Video Player Demo',
      home: VideoPlayerScreen(),
    );
  }
}

//Code defining sURI and then instantiating Widget
Text sURI = Text(
        'https://flutter.github.io/assets-for-api-docs/assets/videos/butterfly.mp4');



onPressed: () {
   Navigator.push(
      context,
      MaterialPageRoute(
         builder: (context) => VideoPlayerApp(uri: sURI),
      ),
   );
},

标签： flutterparametersnamed

Answer 1

您应该定义uri为String，而不是Text。

试试这个：

class VideoPlayerApp extends StatelessWidget {
  VideoPlayerApp({
    Key key,
    this.uri,
  }) : super(key: key);

  final String uri;

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Video Player Demo',
      home: VideoPlayerScreen(),
    );
  }
}