Flutter网络请求优化插件okhi_flutter的使用

当然，下面是一个关于如何在Flutter项目中使用okhi_flutter插件进行网络请求优化的代码案例。okhi_flutter是OkHttp客户端的Flutter封装，OkHttp是一个高效的HTTP客户端，支持连接池、GZIP和HTTP/2等功能。

首先，确保你的Flutter项目已经配置好并添加了okhi_flutter依赖。在pubspec.yaml文件中添加以下依赖：

dependencies:
  flutter:
    sdk: flutter
  okhi_flutter: ^x.y.z  # 请替换为最新版本号

然后，运行flutter pub get来获取依赖。

接下来，我们来看一个完整的代码示例，展示如何使用okhi_flutter进行网络请求。

1. 初始化OkHttpClient

创建一个单例的OkHttpClient实例，这样可以复用连接池等资源，提高效率。

import 'package:okhi_flutter/okhi_flutter.dart';

class OkHttpClientSingleton {
  static final OkHttpClientSingleton _instance = OkHttpClientSingleton._internal();
  OkHttpClient? _client;

  OkHttpClientSingleton._internal();

  factory OkHttpClientSingleton() => _instance;

  OkHttpClient get client {
    _client ??= OkHttpClient();
    return _client!;
  }
}

2. 创建请求并进行网络调用

使用OkHttpClient发送GET请求。

import 'package:flutter/material.dart';
import 'package:okhi_flutter/okhi_flutter.dart';
import 'package:okhi_flutter/request.dart';
import 'dart:convert';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('OkHi Flutter Example'),
        ),
        body: Center(
          child: FutureBuilder<String>(
            future: fetchData(),
            builder: (context, snapshot) {
              if (snapshot.connectionState == ConnectionState.done) {
                if (snapshot.hasError) {
                  return Text('Error: ${snapshot.error}');
                } else {
                  return Text('Response: ${snapshot.data!}');
                }
              } else {
                return CircularProgressIndicator();
              }
            },
          ),
        ),
      ),
    );
  }
}

Future<String> fetchData() async {
  final client = OkHttpClientSingleton().client;

  final request = Request.builder()
    ..url = 'https://jsonplaceholder.typicode.com/posts/1'
    ..method = 'GET';

  try {
    final response = await client.newCall(request.build()).execute();
    if (response.isSuccessful) {
      final responseBody = await response.body.string();
      return jsonDecode(responseBody)['title'];
    } else {
      throw Exception('Failed to load data: ${response.code}');
    }
  } catch (e) {
    throw Exception('Network error: $e');
  }
}

3. 错误处理和重试机制

在实际应用中，你可能需要添加错误处理和重试机制。以下是一个简单的示例，展示如何添加重试逻辑。

Future<String> fetchDataWithRetry(int retries) async {
  final client = OkHttpClientSingleton().client;

  final request = Request.builder()
    ..url = 'https://jsonplaceholder.typicode.com/posts/1'
    ..method = 'GET';

  for (int attempt = 1; attempt <= retries; attempt++) {
    try {
      final response = await client.newCall(request.build()).execute();
      if (response.isSuccessful) {
        final responseBody = await response.body.string();
        return jsonDecode(responseBody)['title'];
      } else {
        throw Exception('Failed to load data: ${response.code}');
      }
    } catch (e) {
      if (attempt < retries) {
        print('Attempt $attempt failed, retrying...');
      } else {
        throw Exception('Network error after $retries attempts: $e');
      }
    }
  }
}

在调用时，可以使用带重试次数的函数：

@override
Widget build(BuildContext context) {
  return MaterialApp(
    home: Scaffold(
      appBar: AppBar(
        title: Text('OkHi Flutter Example'),
      ),
      body: Center(
        child: FutureBuilder<String>(
          future: fetchDataWithRetry(3), // 尝试3次
          builder: (context, snapshot) {
            if (snapshot.connectionState == ConnectionState.done) {
              if (snapshot.hasError) {
                return Text('Error: ${snapshot.error}');
              } else {
                return Text('Response: ${snapshot.data!}');
              }
            } else {
              return CircularProgressIndicator();
            }
          },
        ),
      ),
    ),
  );
}

这个示例展示了如何使用okhi_flutter插件在Flutter中进行网络请求，并包含了一些基本的优化措施，如单例OkHttpClient实例和重试机制。你可以根据实际需求进一步扩展和优化代码。