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                import 'package:flutter/material.dart';

void main() {

// ListView.custom
// 自定义列表
// childrenDelegate 必传参数,
// 需要传入一个实现了 SliverChildDelegate 抽象类的组件,
// 用来给 ListView 组件添加列表项
// 它的实现类有 SliverChildListDelegate 和 SliverChildBuilderDelegate
class ListViewWidget extends StatelessWidget {
  Widget build(BuildContext context) {
    List<Widget> _items = List<Widget>.generate(
      (index) => Container(
        padding: EdgeInsets.all(16.0),
        child: Text("Item $index"),
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('ListView.custom'),
        body: ListView.custom(
          childrenDelegate: SliverChildListDelegate(_items),