Flutter网络通信桥接插件netbridge的使用

当然，以下是一个关于如何在Flutter项目中使用netbridge插件来实现网络通信桥接的示例代码。netbridge插件允许你在Flutter应用中与原生代码（iOS和Android）进行网络通信。需要注意的是，实际开发中netbridge插件的具体API和用法可能会有所不同，以下示例假设netbridge插件提供了基本的网络通信功能。

1. 添加依赖

首先，在你的pubspec.yaml文件中添加netbridge依赖：

dependencies:
  flutter:
    sdk: flutter
  netbridge: ^latest_version  # 请替换为实际的最新版本号

然后运行flutter pub get来获取依赖。

2. 配置原生代码

对于iOS，你可能需要在Info.plist中添加必要的权限声明。对于Android，你可能需要在AndroidManifest.xml中添加网络权限。这些配置取决于netbridge插件的具体要求，以下是一个假设性的Android权限配置示例：

<!-- 在AndroidManifest.xml中添加 -->
<uses-permission android:name="android.permission.INTERNET" />

3. 使用netbridge进行网络通信

初始化netbridge

在你的Flutter应用中，首先需要初始化netbridge：

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

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('NetBridge Example'),
        ),
        body: NetBridgeExample(),
      ),
    );
  }
}

class NetBridgeExample extends StatefulWidget {
  @override
  _NetBridgeExampleState createState() => _NetBridgeExampleState();
}

class _NetBridgeExampleState extends State<NetBridgeExample> {
  NetBridge? _netBridge;

  @override
  void initState() {
    super.initState();
    // 初始化NetBridge
    _netBridge = NetBridge();
    _netBridge!.init();
  }

  @override
  void dispose() {
    // 释放资源
    _netBridge?.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Center(
      child: ElevatedButton(
        onPressed: () async {
          // 调用原生代码进行网络通信
          String response = await _sendNetworkRequest();
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text('Response: $response')),
          );
        },
        child: Text('Send Network Request'),
      ),
    );
  }

  Future<String> _sendNetworkRequest() async {
    // 假设netbridge提供了一个发送GET请求的方法
    Map<String, dynamic> params = {
      'url': 'https://api.example.com/data',
      'method': 'GET',
    };
    var result = await _netBridge!.callHandler('sendRequest', params);
    return result['response'] as String;
  }
}

原生代码实现（示例）

对于iOS和Android，你需要在原生代码中实现sendRequest这个handler。以下是一个假设性的原生代码实现示例。

iOS (Swift):

// 在AppDelegate.swift或你选择的桥接文件中
import UIKit
import Flutter

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    GeneratedPluginRegistrant.register(with: self)
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }

  override func applicationSupportedContentTypes(_ application: UIApplication) -> Set<UTType> {
    return Set()
  }
}

class NetBridgeHandler: NSObject, FlutterPlugin {
  public static func register(with registrar: FlutterRegistrar) {
    let channel = FlutterMethodChannel(name: "netbridge", binaryMessenger: registrar.messenger())
    let instance = NetBridgeHandler()
    registrar.addMethodCallDelegate(instance, channel: channel)
  }

  func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
    if call.method == "sendRequest" {
      guard let arguments = call.arguments as? [String: Any],
            let urlString = arguments["url"] as? String,
            let method = arguments["method"] as? String else {
        result("Invalid arguments")
        return
      }

      let url = URL(string: urlString)!
      var request = URLRequest(url: url)
      request.httpMethod = method

      let session = URLSession.shared
      let task = session.dataTask(with: request) { data, response, error in
        if let data = data, let responseString = String(data: data, encoding: .utf8) {
          result(responseString)
        } else if let error = error {
          result("Error: \(error.localizedDescription)")
        } else {
          result("Unknown error")
        }
      }
      task.resume()
    } else {
      result(FlutterMethodNotImplemented)
    }
  }
}

Android (Kotlin):

// 在MainActivity.kt或你选择的桥接文件中
package com.example.yourapp

import android.os.Bundle
import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine
import io.flutter.plugin.common.MethodCall
import io.flutter.plugin.common.MethodChannel
import io.flutter.plugins.GeneratedPluginRegistrant
import okhttp3.OkHttpClient
import okhttp3.Request

class MainActivity: FlutterActivity() {
    private val CHANNEL = "netbridge"

    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        super.configureFlutterEngine(flutterEngine)
        GeneratedPluginRegistrant.registerWith(flutterEngine)

        MethodChannel(flutterEngine.dartExecutor.binaryMessenger, CHANNEL).setMethodCallHandler { call, result ->
            if (call.method == "sendRequest") {
                val arguments = call.arguments as? Map<String, Any>
                val url = arguments?.getString("url")
                val method = arguments?.getString("method")

                url?.let {
                    val client = OkHttpClient()
                    val request = Request.Builder().url(it).method(method ?: "GET", null).build()
                    client.newCall(request).enqueue { response ->
                        response.body?.string()?.let { body ->
                            result.success(body)
                        } ?: run {
                            result.error("UNAVAILABLE", "No response body", null)
                        }
                    }
                } ?: run {
                    result.error("INVALID_ARGUMENT", "Missing URL", null)
                }
            } else {
                result.notImplemented()
            }
        }
    }
}

以上代码展示了如何在Flutter中使用netbridge插件与原生代码进行网络通信的基本流程。实际使用中，请查阅netbridge插件的官方文档以获取准确的API和配置信息。