fluttergo_1">为什么flutter要用go写工具类

在Flutter 应用中，有些场景涉及到大量的计算，比如复杂的加密算法、数据压缩 / 解压缩或者图形处理中的数学计算等

1. 下载pigeon插件模版

base_plugin

2. 编写go代码

//greeting.go
package greetingimport "fmt"func SayHi(text string) string {return text
}
func Hello(name string) {fmt.Printf("Hello %s!\n", name)
}

3.生成greeting.aar，Greeting.xcframework

gomobile bind -target=ios
gomobile bind -target=android -androidapi 26
go get golang.org/x/mobile/bind/objc （可选）
go get golang.org/x/mobile/bind （可选）

4. ios

1. Greeting.xcframework拷贝到base_plugin/ios
2. 修改base_plugin.podspec
   添加 s.vendored_frameworks = ‘Greeting.xcframework’
3. 修改ios/Classes/BasePlugin.swift
4. 如果运行报错，就删除build

#
# To learn more about a Podspec see http://guides.cocoapods.org/syntax/podspec.html.
# Run `pod lib lint base_plugin.podspec` to validate before publishing.
#
Pod::Spec.new do |s|s.name             = 'base_plugin's.version          = '0.0.1's.summary          = 'A new Flutter project.'s.description      = <<-DESC
A new Flutter project.DESCs.homepage         = 'http://example.com's.license          = { :file => '../LICENSE' }s.author           = { 'Your Company' => 'email@example.com' }s.source           = { :path => '.' }s.source_files = 'Classes/**/*'s.dependency 'Flutter's.platform = :ios, '11.0'# Flutter.framework does not contain a i386 slice.s.pod_target_xcconfig = { 'DEFINES_MODULE' => 'YES', 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'i386' }s.swift_version = '5.0'# 添加框架路径s.vendored_frameworks = 'Greeting.xcframework'
end

swift">//BasePlugin.swift
import Flutter
import UIKit
import Greeting
public class BasePlugin: NSObject, FlutterPlugin,HostMessageApi {private static var flutterAPI: FlutterMessageApi? = nilpublic static func register(with registrar: any FlutterPluginRegistrar) {let api = BasePlugin()HostMessageApiSetup.setUp(binaryMessenger: registrar.messenger(), api: api)flutterAPI = FlutterMessageApi(binaryMessenger: registrar.messenger())}func flutter2Native(message: String, type: Int64) throws -> String {print("ios->flutter2Native=>start=>message=\(message)=type=\(type)");if type==1 {GreetingHello("调用hello")return "GreetingHello"} else if type==2{return GreetingSayHi("调用SayHi")}else{return "ios->flutter2Native=>start=>message=\(message)=type=\(type)"}}func flutter2NativeAsync(message: String, type: Int64, completion: @escaping (Result<String, any Error>) -> Void) {print("ios->flutter2NativeAsyncMessage===2")completion(.success(message))}}

5. android

1. 拷贝greeting.aar到android/libs/，没有libs就创建一个
2. 修改android/build.gradle
3. 修改BasePlugin.kt
4. 新开一个窗口，打开插件下面的example下面的android项目，方便修改BasePlugin.kt代码

//build.gradle
rootProject.allprojects {repositories {google()mavenCentral()flatDir {dirs project(':base_plugin').file('libs')}}
}
dependencies {implementation(name: "greeting", ext: "aar")
}

kotlin">//BasePlugin.kt
package com.app.base_pluginimport androidx.annotation.NonNull
import io.flutter.embedding.engine.plugins.FlutterPlugin
import greeting.Greeting/** BasePlugin */
class BasePlugin : FlutterPlugin, HostMessageApi {/// The MethodChannel that will the communication between Flutter and native Android////// This local reference serves to register the plugin with the Flutter Engine and unregister it/// when the Flutter Engine is detached from the Activityprivate lateinit var flutterMessageApi: FlutterMessageApioverride fun onAttachedToEngine(@NonNull flutterPluginBinding: FlutterPlugin.FlutterPluginBinding) {print("onAttachedToEngine")HostMessageApi.setUp(flutterPluginBinding.binaryMessenger, this)flutterMessageApi = FlutterMessageApi(flutterPluginBinding.binaryMessenger)}override fun onDetachedFromEngine(@NonNull binding: FlutterPlugin.FlutterPluginBinding) {HostMessageApi.setUp(binding.binaryMessenger, null)}override fun flutter2Native(message: String, type: Long): String {print("flutter2Native=message=start=>$message=type=$type")flutterMessageApi.native2Flutter("input params=>2222", callback = {print("response=>${it.getOrNull()}")}, typeArg = 1)when (type) {1L -> {Greeting.Hello("111111")return "Greeting.Hello"}2L -> {return Greeting.sayHi("flutter2Native=message=$message=type=$type")}else -> {return "flutter2Native=message=$message=type=$type"}}}override fun flutter2NativeAsync(message: String,type: Long,callback: (Result<String>) -> Unit) {fun d(e: Result<String>) {print("d")}print("flutter2NativeAsync=message=$message=type=$type")flutterMessageApi.native2FlutterAsync("2222", callback = {print("222")}, typeArg = 2)callback(Result.success("flutter2NativeAsync=message=$message=type=$type"));}
}

6. dart中使用

import 'package:base_plugin/base_plugin.dart';
import 'package:base_plugin/messages.g.dart';
import 'package:flutter/material.dart';
import 'dart:async';import 'package:flutter/services.dart';void main() {runApp(const MyApp());
}class MyApp extends StatefulWidget {const MyApp({super.key});@overrideState<MyApp> createState() => _MyAppState();
}class _MyAppState extends State<MyApp>  implements FlutterMessageApi{String _platformVersion = 'Unknown';final _basePlugin = BasePlugin();@overridevoid initState() {super.initState();initPlatformState();FlutterMessageApi.setUp(this);}// Platform messages are asynchronous, so we initialize in an async method.Future<void> initPlatformState() async {String platformVersion;// Platform messages may fail, so we use a try/catch PlatformException.// We also handle the message potentially returning null.try {platformVersion =await BasePlugin.flutter2Native("33344", 0);} on PlatformException {platformVersion = 'Failed to get platform version.';}// If the widget was removed from the tree while the asynchronous platform// message was in flight, we want to discard the reply rather than calling// setState to update our non-existent appearance.if (!mounted) return;setState(() {_platformVersion = platformVersion;});}@overrideWidget build(BuildContext context) {return MaterialApp(home: Scaffold(appBar: AppBar(title: const Text('Plugin example app'),),body: Column(children: [Text('Running on: $_platformVersion\n'),TextButton(onPressed: () async {final result =await BasePlugin.flutter2Native("33344", 0);print("flutter2Native=$result");}, child: const Text("调用插件方法"))],),),);}@overrideString native2Flutter(String message, int type) {print("native2Flutter=$message $type");return "native2Flutter=$message";}@overrideFuture<String> native2FlutterAsync(String message, int type) {print("native2FlutterAsync=$message  $type");return Future(() => "native2FlutterAsync=$message");}
}