问颤动类型“List<dynamic>”不是类型“list<Widget>”的子类型

EN

import 'package:flutter/material.dart';

  class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
        home:new MyCard()
    );
  }
}

class MyCard extends StatelessWidget{
  List cards = new List.generate(20, (i)=>new CustomCard());
  @override
  Widget build(BuildContext context) {
      return new Scaffold(
            appBar: new AppBar(
              title: new Text('Car Results'),
              backgroundColor:new Color(0xFF673AB7),
            ),
            body: new Container(
              child: new ListView(
                children: cards,
              )
            )
        );

    }
}

class CustomCard extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
              return  new Card(
                    child: new Column(
                      children: <Widget>[
                        new Image.network('https://matwrites.com/wp-content/uploads/2018/03/Flutter.png'),
                        new Padding(
                          padding: new EdgeInsets.all(7.0),
                          child: new Row(
                            children: <Widget>[
                             new Padding(
                               padding: new EdgeInsets.all(7.0),
                               child: new Icon(Icons.thumb_up),
                             ),
                             new Padding(
                               padding: new EdgeInsets.all(7.0),
                               child: new Text('Like',style: new TextStyle(fontSize: 18.0),),
                             ),
                             new Padding(
                               padding: new EdgeInsets.all(7.0),
                               child: new Icon(Icons.comment),
                             ),
                             new Padding(
                               padding: new EdgeInsets.all(7.0),
                               child: new Text('Comments',style: new TextStyle(fontSize: 18.0)),
                             )

                            ],
                          )
                        )
                      ],
                    ),
                  );
  }
}