Flutter无限滚动功能插件infinity_scroll_shell的使用

InfinityScrollShell 是一个用于 Flutter 应用程序的 widget，它简化了实现无限滚动功能的过程。当用户滚动 ListView 时，它会自动获取更多数据。

目录

• 使用
• 许可

使用

示例代码

以下是一个完整的示例代码，展示了如何在 Flutter 应用程序中使用 InfinityScrollShell 插件来实现无限滚动功能。

import 'package:flutter/material.dart';
import 'package:infinity_scroll_shell/infinity_scroll_shell.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      title: 'Flutter Demo',
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  bool _isLoading = false;

  // 初始化列表数据
  final List<String> _list = List.generate(
    50,
    (index) => "$index",
  ).toList();

  // 当滚动到底部时触发此函数以加载更多数据
  Future<void> _maxScrollExtentObserverFn() async {
    if (_isLoading) return;
    _isLoading = true;
    setState(() {});

    // 生成新的数据并添加到列表中
    final addList = List.generate(10, (index) => "${_list.length + index}").toList();
    _list.addAll(addList);
    setState(() {});

    // 模拟网络请求延迟
    await Future.delayed(const Duration(milliseconds: 100));

    _isLoading = false;
    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: Text(widget.title),
      ),
      body: InfinityScrollShell(
        maxScrollExtentObserverFn: _maxScrollExtentObserverFn,
        child: ListView.builder(
          shrinkWrap: true,
          physics: const NeverScrollableScrollPhysics(),
          itemCount: _list.length,
          itemBuilder: (context, index) {
            final text = _list[index];
            return Container(
              alignment: Alignment.center,
              padding: const EdgeInsets.symmetric(vertical: 12),
              child: Text(
                text,
                style: const TextStyle(fontSize: 20),
              ),
            );
          },
        ),
      ),
    );
  }
}

代码解释

1. 导入必要的包：

   import 'package:flutter/material.dart';
   import 'package:infinity_scroll_shell/infinity_scroll_shell.dart';
   

2. 初始化应用：

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

3. 定义应用的基本结构：

   class MyApp extends StatelessWidget {
     const MyApp({super.key});
   
     @override
     Widget build(BuildContext context) {
       return const MaterialApp(
         title: 'Flutter Demo',
         home: MyHomePage(title: 'Flutter Demo Home Page'),
       );
     }
   }
   

4. 定义主页状态类：

   class MyHomePage extends StatefulWidget {
     const MyHomePage({super.key, required this.title});
   
     final String title;
   
     @override
     State<MyHomePage> createState() => _MyHomePageState();
   }
   

5. 实现主页状态类：

   class _MyHomePageState extends State<MyHomePage> {
     bool _isLoading = false;
   
     // 初始化列表数据
     final List<String> _list = List.generate(
       50,
       (index) => "$index",
     ).toList();
   
     // 当滚动到底部时触发此函数以加载更多数据
     Future<void> _maxScrollExtentObserverFn() async {
       if (_isLoading) return;
       _isLoading = true;
       setState(() {});
   
       // 生成新的数据并添加到列表中
       final addList = List.generate(10, (index) => "${_list.length + index}").toList();
       _list.addAll(addList);
       setState(() {});
   
       // 模拟网络请求延迟
       await Future.delayed(const Duration(milliseconds: 100));
   
       _isLoading = false;
       setState(() {});
     }
   
     @override
     Widget build(BuildContext context) {
       return Scaffold(
         appBar: AppBar(
           backgroundColor: Theme.of(context).colorScheme.inversePrimary,
           title: Text(widget.title),
         ),
         body: InfinityScrollShell(
           maxScrollExtentObserverFn: _maxScrollExtentObserverFn,
           child: ListView.builder(
             shrinkWrap: true,
             physics: const NeverScrollableScrollPhysics(),
             itemCount: _list.length,
             itemBuilder: (context, index) {
               final text = _list[index];
               return Container(
                 alignment: Alignment.center,
                 padding: const EdgeInsets.symmetric(vertical: 12),
                 child: Text(
                   text,
                   style: const TextStyle(fontSize: 20),
                 ),
               );
             },
           ),
         ),
       );
     }
   }