Flutter热重载插件reload_widget的使用

reload_widget 是一个用于 Flutter 应用的组件，它允许用户在数据获取失败时点击重新加载。本示例将展示如何在 Flutter 中使用 reload_widget。

使用方法

以下是一个简单的示例代码，展示了如何在 Flutter 应用中使用 reload_widget。

示例代码

import 'dart:math';

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

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

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Reload widget Demo',
      theme: ThemeData(primarySwatch: Colors.blue),
      home: const MyHomePage(title: 'Reload widget Demo Home Page')
    );
  }
}

class MyHomePage extends StatefulWidget {
  final String title;

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

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

class _MyHomePageState extends State<MyHomePage> {
  ReloadStatus _customStatus = ReloadStatus.none;
  int _data = 0;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      floatingActionButton: FloatingActionButton(
        child: const Icon(Icons.refresh),
        onPressed: () {
          setState(() {
            _customStatus = ReloadStatus.timeout;
          });
        }
      ),
      body: ReloadWidget(
        customStatus: _customStatus,
        (BuildContext builderContext, ReloadStatus status) {
          return Center(
            child: Text(
              'Data: $_data\nStatus: $status',
              style: const TextStyle(
                fontSize: 24,
                fontWeight: FontWeight.w700,
                color: Colors.green
              )
            )
          );
        },
        onReload: () async {
          // 模拟 API 调用
          final bool result = await Future.delayed(const Duration(seconds: 1)).then(
            (value) => Future.value(Random(DateTime.now().millisecond).nextBool())
          );

          _data = Random().nextInt(999);

          if (result) {
            return Random(DateTime.now().millisecond).nextBool()
                    ? ReloadStatus.succeeded
                    : ReloadStatus.failed;
          } else {
            return ReloadStatus.timeout;
          }
        }
      )
    );
  }
}

代码解释

1. 导入库

   import 'dart:math';
   import 'package:flutter/material.dart';
   import 'package:reload_widget/reload_widget.dart';
   

2. 主应用入口

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

3. 定义主应用类

   class MyApp extends StatelessWidget {
     const MyApp({super.key});
   
     @override
     Widget build(BuildContext context) {
       return MaterialApp(
         title: 'Reload widget Demo',
         theme: ThemeData(primarySwatch: Colors.blue),
         home: const MyHomePage(title: 'Reload widget Demo Home Page')
       );
     }
   }
   

4. 定义主页状态类

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

5. 定义主页状态

   class _MyHomePageState extends State<MyHomePage> {
     ReloadStatus _customStatus = ReloadStatus.none;
     int _data = 0;
   
     @override
     Widget build(BuildContext context) {
       return Scaffold(
         appBar: AppBar(title: Text(widget.title)),
         floatingActionButton: FloatingActionButton(
           child: const Icon(Icons.refresh),
           onPressed: () {
             setState(() {
               _customStatus = ReloadStatus.timeout;
             });
           }
         ),
         body: ReloadWidget(
           customStatus: _customStatus,
           (BuildContext builderContext, ReloadStatus status) {
             return Center(
               child: Text(
                 'Data: $_data\nStatus: $status',
                 style: const TextStyle(
                   fontSize: 24,
                   fontWeight: FontWeight.w700,
                   color: Colors.green
                 )
               )
             );
           },
           onReload: () async {
             // 模拟 API 调用
             final bool result = await Future.delayed(const Duration(seconds: 1)).then(
               (value) => Future.value(Random(DateTime.now().millisecond).nextBool())
             );
   
             _data = Random().nextInt(999);
   
             if (result) {
               return Random(DateTime.now().millisecond).nextBool()
                       ? ReloadStatus.succeeded
                       : ReloadStatus.failed;
             } else {
               return ReloadStatus.timeout;
             }
           }
         )
       );
     }
   }