flutter和原生利用pigeon建立通道-编程知识

首先导入依赖：

dependencies:
pigeon: ^10.0.0

定义一个文件：

/// 用于定于flutter和平台的桥接方法
/// @HostApi() 标记的，是用于 Flutter 调用原生的方法；
/// @FlutterApi() 标记的，是用于原生调用 Flutter 的方法；
/// @async 如果原生的方法，是步回调那种，你就可以使用这个标记；
/// 在项目根目录，运行以下命令生成平台代码
/// dart run pigeon --input pigeons/messages.dartimport 'package:pigeon/pigeon.dart';@ConfigurePigeon(PigeonOptions(dartOut: 'lib/pigeons/pigeon.dart',dartOptions: DartOptions(),// objcHeaderOut: '../isolarCloud/operation4ios/Flutter/SGFlutterBridge.h',// objcSourceOut: '../isolarCloud/operation4ios/Flutter/SGFlutterBridge.m',// objcOptions: ObjcOptions(),kotlinOut:'../iSolarCloud/LibBase/src/main/java/com/isolarcloud/libbase/flutter/SGFlutterBridge.kt',kotlinOptions: KotlinOptions(),
))
class CommonParams {String? pageName;Map<String?, Object?>? arguments;
}
class ApiParams {String? url;Map<String?, Object?>? arguments;
}/// Flutter调用原生的Api，全部放在一个抽象类中即可
@HostApi()abstract class SGHostApi {/// push至原生页面，参数：页面名称、参数void pushNativePage(CommonParams params);/// pop出当前页面，预留参数，可通过params.pageName pop到指定页面void popPage(CommonParams? params);/// 通过Key获取本地化文本数据（同步）String getLocalizedText(String? key);/// Flutter通过URL和arguments调用原生端接口，异步返回数据给Flutter端@asyncMap requestNativeApi(ApiParams apiParams);/// 是否允许开启Native页面的原生手势返回效果void enablePopRecognizer(bool enable);
}

运行命令行：
dart run pigeon --input pigeons/messages.dart

接着可以运行下：flutter pub get 的命令

自动会生成这个文件：

里面会实现SGHostApi的定义的方法：比如下面的方法就是自动生成：

/// push至原生页面，参数：页面名称、参数
Future<void> pushNativePage(CommonParams arg_params) async {final BasicMessageChannel<Object?> channel = BasicMessageChannel<Object?>('dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.pushNativePage', codec,binaryMessenger: _binaryMessenger);final List<Object?>? replyList =await channel.send(<Object?>[arg_params]) as List<Object?>?;if (replyList == null) {throw PlatformException(code: 'channel-error',message: 'Unable to establish connection on channel.',);} else if (replyList.length > 1) {throw PlatformException(code: replyList[0]! as String,message: replyList[1] as String?,details: replyList[2],);} else {return;}
}

注意打开这个代码注释：意思是在你Android项目的某个路径下生成SGFlutterBridge文件。

kotlinOut:'../iSolarCloud/LibBase/src/main/java/com/isolarcloud/flutter/SGFlutterBridge.kt',
kotlinOptions: KotlinOptions(),

然后会在：上面这个路径下自动生成和原生的桥接方法，这里执行的是Android的方法，ios只需要打开：

  // objcHeaderOut: '../isolarCloud/operation4ios/Flutter/SGFlutterBridge.h',// objcSourceOut: '../isolarCloud/operation4ios/Flutter/SGFlutterBridge.m',// objcOptions: ObjcOptions(),

我们先看看原生和flutter项目的依赖：

在Android的项目settings.gradle中配置引用：

setBinding(new Binding([gradle: this]))
evaluate(new File(settingsDir,'../isolarcloud_flutter/.android/include_flutter.groovy')
)

以上操作就把两个项目关联在一起了。下面是自动生成的桥接方法，pigeon自动帮你实现：

/*** Flutter调用原生的Api，全部放在一个抽象类中即可** Generated interface from Pigeon that represents a handler of messages from Flutter.*/
interface SGHostApi {/** push至原生页面，参数：页面名称、参数 */fun pushNativePage(params: CommonParams)/** pop出当前页面，预留参数，可通过params.pageName pop到指定页面 */fun popPage(params: CommonParams?)/** Flutter通过URL和arguments调用原生端接口，异步返回数据给Flutter端 */fun requestNativeApi(apiParams: ApiParams, callback: (Result<String?>) -> Unit)/** 是否允许开启Native页面的原生手势返回效果 */fun enablePopRecognizer(enable: Boolean)/*** 调用原生toast* type:0 老版，1：国内，2：海外样式*/fun showToast(type: AppType, msg: String)/*** 调用原生toast* type:0 老版，1：国内，2：海外样式*/fun showLoading(show: Boolean, type: AppType, msg: String?)/** 获取用户信息 */fun getUserInfo(): String?companion object {/** The codec used by SGHostApi. */val codec: MessageCodec<Any?> by lazy {SGHostApiCodec}/** Sets up an instance of `SGHostApi` to handle messages through the `binaryMessenger`. */@Suppress("UNCHECKED_CAST")fun setUp(binaryMessenger: BinaryMessenger, api: SGHostApi?) {run {val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.pushNativePage", codec)if (api != null) {channel.setMessageHandler { message, reply ->val args = message as List<Any?>val paramsArg = args[0] as CommonParamsvar wrapped: List<Any?>try {api.pushNativePage(paramsArg)wrapped = listOf<Any?>(null)} catch (exception: Throwable) {wrapped = wrapError(exception)}reply.reply(wrapped)}} else {channel.setMessageHandler(null)}}run {val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.popPage", codec)if (api != null) {channel.setMessageHandler { message, reply ->val args = message as List<Any?>val paramsArg = args[0] as CommonParams?var wrapped: List<Any?>try {api.popPage(paramsArg)wrapped = listOf<Any?>(null)} catch (exception: Throwable) {wrapped = wrapError(exception)}reply.reply(wrapped)}} else {channel.setMessageHandler(null)}}run {val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.requestNativeApi", codec)if (api != null) {channel.setMessageHandler { message, reply ->val args = message as List<Any?>val apiParamsArg = args[0] as ApiParamsapi.requestNativeApi(apiParamsArg) { result: Result<String?> ->val error = result.exceptionOrNull()if (error != null) {reply.reply(wrapError(error))} else {val data = result.getOrNull()reply.reply(wrapResult(data))}}}} else {channel.setMessageHandler(null)}}run {val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.enablePopRecognizer", codec)if (api != null) {channel.setMessageHandler { message, reply ->val args = message as List<Any?>val enableArg = args[0] as Booleanvar wrapped: List<Any?>try {api.enablePopRecognizer(enableArg)wrapped = listOf<Any?>(null)} catch (exception: Throwable) {wrapped = wrapError(exception)}reply.reply(wrapped)}} else {channel.setMessageHandler(null)}}run {val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.showToast", codec)if (api != null) {channel.setMessageHandler { message, reply ->val args = message as List<Any?>val typeArg = AppType.ofRaw(args[0] as Int)!!val msgArg = args[1] as Stringvar wrapped: List<Any?>try {api.showToast(typeArg, msgArg)wrapped = listOf<Any?>(null)} catch (exception: Throwable) {wrapped = wrapError(exception)}reply.reply(wrapped)}} else {channel.setMessageHandler(null)}}run {val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.showLoading", codec)if (api != null) {channel.setMessageHandler { message, reply ->val args = message as List<Any?>val showArg = args[0] as Booleanval typeArg = AppType.ofRaw(args[1] as Int)!!val msgArg = args[2] as String?var wrapped: List<Any?>try {api.showLoading(showArg, typeArg, msgArg)wrapped = listOf<Any?>(null)} catch (exception: Throwable) {wrapped = wrapError(exception)}reply.reply(wrapped)}} else {channel.setMessageHandler(null)}}run {val channel = BasicMessageChannel<Any?>(binaryMessenger, "dev.flutter.pigeon.isolarcloud_flutter.SGHostApi.getUserInfo", codec)if (api != null) {channel.setMessageHandler { _, reply ->var wrapped: List<Any?>try {wrapped = listOf<Any?>(api.getUserInfo())} catch (exception: Throwable) {wrapped = wrapError(exception)}reply.reply(wrapped)}} else {channel.setMessageHandler(null)}}}}
}

同步或者异步的去调用自动生成的方法：

Future<void> makeApiCall() async {var arguments = {"curPage": 1, "size": 10, "message_scene_code": 2};final stopwatch = Stopwatch()..start();await SGHostApi().requestNativeApi(ApiParams(arguments: arguments)).then((value) {print("数据回来的时间：${DateTime.now().millisecondsSinceEpoch}");stopwatch.stop();print("总共花费时间：${stopwatch.elapsedMilliseconds}毫秒");toast = "android 返回的数据==$value";// print("value===$value");setState(() {});});
}_getString(){SGHostApi().getLocalizedText("I18N_COMMON_SERVICE_AGREEMENT_DESCRIPTION").then((value){print("android 给过来的数据==$value");});setState(() {});
}

Android的代码：

class SingleFlutterActivity : FlutterActivity(), EngineBindingsDelegate {private val engineBindings: EngineBindings by lazy {EngineBindings(activity = this, delegate = this, entrypoint = FlutterRouter.DEMO_ENTRY_POINTER, initialRoute = "${FlutterRouter.DEMO_ROUTER}?psId=1234")}override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)engineBindings.attach()/*** flutter 调用原生的方法* */SGHostApiget.setUp(getFlutterEngine()!!.getDartExecutor().getBinaryMessenger(), MyApi())SGHostApi.setUp(getFlutterEngine()!!.getDartExecutor().getBinaryMessenger(),FlutterToNativeApi() )}override fun onDestroy() {super.onDestroy()engineBindings.detach()}override fun provideFlutterEngine(context: Context): FlutterEngine? {return engineBindings.engine}override fun onNext() {val flutterIntent = Intent(this, LoginActivity::class.java)startActivity(flutterIntent)}/*** flutter 调用原生的方法,原生写法* */override fun onNext(str: String?) {val flutterIntent = Intent(this, FlutterToAndroidActivity::class.java)flutterIntent.putExtra("extraString", str)startActivity(flutterIntent)}/*** flutter 调用原生的方法* */class MyApi : SGHostApiget {override fun getString(): String {println("测试===6666")return "测试===6666，这里是Android的方法"}}/*** flutter 调用原生的方法* */class FlutterToNativeApi() : SGHostApi {/*** flutter调用原生跳原生页面* */override fun pushNativePage(params: CommonParams) {//params.pageName 页面名称非类名，不可直接创建实例/*val flutterIntent = Intent(this, params::class.java)flutterIntent.putExtra("extraString", str)startActivity(flutterIntent)*/}/*** flutter调用原生跳原生页面* */override fun popPage(params: CommonParams?) {//flutter调用Android去退出页面}/*** flutter调用原生 获取国际化字符串* */override fun getLocalizedText(key: String?): String {return I18nUtil.getString(key);}/*** flutter调用原生 获取网络信息 异步* */override fun requestNativeApi(apiParams: ApiParams,callback: (Result<Map<Any, Any?>>) -> Unit,) {/*val bitmap: Bitmap = BitmapFactory.decodeResource(BaseApplication.getApplication().resources, R.drawable.test_image)val outputStream: ByteArrayOutputStream = ByteArrayOutputStream()bitmap.compress(Bitmap.CompressFormat.PNG, 50, outputStream)val size: Int = outputStream.size()println("字节大小: $size")val result: Result<Map<Any, Any?>> = Result.success(mapOf("name" to outputStream),)callback(result)*/val map: MutableMap<String, Any> = HttpRequest.getCommonParamMap()HttpUtil.postWithPath("/v1/devService/getDevModelUpgradeConfigList", /*apiParams.arguments*/map, object : HttpGlobalHandlerCallback<UpdateRequestBean?>() {override fun onSuccess(jsonResult: JsonResults<UpdateRequestBean?>) {// 处理成功返回的数据val data = jsonResult.result_data // 获取数据if (data is UpdateRequestBean) {data as UpdateRequestBean}println("开始传输时间: ${System.currentTimeMillis()}")callback(Result.success(data!!.toMap())) // 通过callback返回结果// 打印字节大小val byteArray = data?.toString()?.toByteArray(Charsets.UTF_8)val size = byteArray?.size ?: 0println("字节大小: $size")}fun UpdateRequestBean.toMap(): Map<Any, Any?> {val map = mutableMapOf<Any, Any?>()map["code"] = codemap["record"] = recordmap["totalFileSize"] = totalFileSizemap["pageList"] = pageList?.map { fileInfo ->mapOf("file_url" to fileInfo.file_url,"file_signature" to fileInfo.file_signature,"file_name" to fileInfo.file_name,"file_id" to fileInfo.file_id,"dev_model" to fileInfo.dev_model,"file_size" to fileInfo.file_size,"type" to fileInfo.type,"dev_type_id" to fileInfo.dev_type_id,"record_id" to fileInfo.record_id,"sn" to fileInfo.sn,"update_time_stamp" to fileInfo.update_time_stamp,"block_flag" to fileInfo.block_flag)}return map}override fun onError(type: ErrorNetType) {super.onError(type)// 处理错误情况// val result: Result<Map<Any, Any?>> = Result.success(//   mapOf(//     "name" to "John",//     "age" to 30,//     "email" to "john@example.com"//   )// )// callback(result)// 通过callback返回错误信息val failureResult: Result<Map<Any, Any?>> = Result.failure(Exception("An error occurred"))callback(failureResult)}override fun onFinish() {super.onFinish()}})}override fun disablePopRecognizer(disable: Boolean) {}}}

在flutter中统一使用这个类来获取原生获取的网络数据：

/// 成功回调
typedef SuccessCallback = void Function(Map<String, dynamic>? resultData, String resultCode, String resultMsg);/// 失败回调
typedef ErrorCallback = void Function();class RequireNativeApi {static void postWithPathOversea(String? url, Map<String?, Object?>? arguments,SuccessCallback? successCallback, ErrorCallback? errorCallback,{bool showToast = true}) {postWithPath(url, arguments, successCallback, errorCallback,showToast: showToast, appType: AppType.oversea);}static void postWithPathDomestic(String? url,Map<String?, Object?>? arguments,SuccessCallback? successCallback,ErrorCallback? errorCallback,{bool showToast = true}) {postWithPath(url, arguments, successCallback, errorCallback,showToast: showToast, appType: AppType.domestic);}static void postWithPath(String? url, Map<String?, Object?>? arguments,SuccessCallback? successCallback, ErrorCallback? errorCallback,{bool showToast = true, AppType appType = AppType.oversea}) {ApiParams apiParams = ApiParams();apiParams.url = url;apiParams.arguments = arguments;sgApi.requestNativeApi(apiParams).then((data) {debugPrint("");debugPrint("======================================================");debugPrint("api: $url");debugPrint("业务入参: $arguments");debugPrint("出参：$data");debugPrint("======================================================");if (data == null || data.isEmpty) {/// 网络异常if (showToast) {sgApi.showToast(appType, SGi18n.key("I18N_COMMON_NETWORK_ERROR"));}if (errorCallback != null) {errorCallback();}return;}var jsonData = json.decode(data);if (successCallback != null) {// 返回接口返回数据，需要调用各个实体类的方法，所以需要各个业务层将Map转为对应的实体类successCallback(jsonData['result_data'] ?? {},jsonData['result_code'] ?? "",jsonData['result_msg'] ?? "",);}}).onError((error, stackTrace) {debugPrint("RequireNativeApi error: $error");debugPrint("RequireNativeApi error: $stackTrace");if (showToast) {sgApi.showToast(appType, SGi18n.key("I18N_COMMON_NETWORK_ERROR_MESSAGE"));}if (errorCallback != null) {errorCallback();}});}
}

flutter中要使用的地方直接拿到成功和失败的回调即可：

RequireNativeApi.postWithPathOversea(Api.getDeleteUserMessage, argument,getDeleteMessageSuccess, () => SGOSLoadingToast.dismissLoading());

我项目中用的是getx，大家可以看看我完整的代码：

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:isolarcloud_flutter/api/api.dart';
import 'package:isolarcloud_flutter/api/require_native_api.dart';
import 'package:isolarcloud_flutter/bean/home_msg_entity.dart';
import 'package:isolarcloud_flutter/bean/update_msg_entity.dart';
import 'package:isolarcloud_flutter/modules/demo/constant/constant_state_id.dart';
import 'package:isolarcloud_flutter/utils/hud/sg_os_loading_toast.dart';
import 'package:isolarcloud_flutter/utils/json_cache_util.dart';import 'sg_message_first_state.dart';class SGMessageHomePageLogic extends GetxController {final SGMessageHomePageState state = SGMessageHomePageState();static const idMessageClearUpdate = "message_clear_update";static const idMessageList = "message_list";static const idLoadFail = "message_load_fail";void getList(String labelStr, {bool isFirst = false}) async {state.labelStr = labelStr;isFirst ? SGOSLoadingToast.showLoading() : null;Map<String, Object> argument = {};var cache = await JsonCacheManageUtils.getCacheData(JsonCacheManageUtils.HomeMessageResponse,labelId: labelStr.toString()).then((value) {if (value != null) {return HomeMsgEntity.fromJson(value as Map<String, dynamic>);}});state.hasCache = false;if (cache is HomeMsgEntity) {state.pageList = cache;state.hasCache = true;update([idMessageList + labelStr.toString()]);}RequireNativeApi.postWithPathOversea(Api.getHomeMessageList, argument, getHomeMessageSuccess, () {isFirst ? SGOSLoadingToast.dismissLoading() : null;update([idLoadFail]);});}void getHomeMessageSuccess(Map<String, dynamic>? resultData, String resultCode, String resultMsg) {if (resultCode == "1" && resultData != null && resultData.isNotEmpty) {JsonCacheManageUtils.saveCacheData(JsonCacheManageUtils.HomeMessageResponse,labelId: state.labelStr,resultData);state.pageList = HomeMsgEntity.fromJson(resultData);}SGOSLoadingToast.dismissLoading();if (!state.hasCache) {update(["$idMessageList${state.labelStr}"]);}}/// clear 消息 传null为全部void updateUserAllMessage(dynamic messageSceneCode) {SGOSLoadingToast.showLoading();Map<String, dynamic> argument = {"is_all": 1,"message_scene_code": messageSceneCode,};RequireNativeApi.postWithPathOversea(Api.getUpdateUserMessage, argument,getClearMessageSuccess, () => SGOSLoadingToast.dismissLoading());}void getClearMessageSuccess(Map<String, dynamic>? resultData, String resultCode, String resultMsg) {if (resultCode == "1" && resultData != null && resultData.isNotEmpty) {state.updateBean = UpdateMsgEntity.fromJson(resultData);}SGOSLoadingToast.dismissLoading();update([idMessageClearUpdate]);}//删除单个消息大类void deleteUserMessage(String? ids, String? messageSceneCode, int index) {SGOSLoadingToast.showLoading();Map<String, dynamic> argument = {"ids": ids,"message_scene_code": messageSceneCode,};state.removeIndex = index;RequireNativeApi.postWithPathOversea(Api.getDeleteUserMessage, argument,getDeleteMessageSuccess, () => SGOSLoadingToast.dismissLoading());}void getDeleteMessageSuccess(Map<String, dynamic>? resultData, String resultCode, String resultMsg) {debugPrint("resultData: $resultData");if (resultCode == "1" && resultData != null && resultData.isNotEmpty) {state.deleteBean = UpdateMsgEntity.fromJson(resultData);}SGOSLoadingToast.dismissLoading();update([StateListenerId.messageDelete]);}///底部按钮删除全部选中的void deleteCheckMessage(List<HomeMsgPageList> messageHomeList) {SGOSLoadingToast.showLoading();StringBuffer messageSceneCodes = StringBuffer();for (int i = 0; i < messageHomeList.length; i++) {String? sceneCode = messageHomeList[i].messageSceneCode;messageSceneCodes.write(sceneCode);if (i != messageHomeList.length - 1) {messageSceneCodes.write(',');}}String result = messageSceneCodes.toString();if (result.isEmpty) {return;}Map<String, dynamic> argument = {"ids": null,"message_scene_code": result,};RequireNativeApi.postWithPathOversea(Api.getDeleteUserMessage, argument,getDeleteMessageSuccess, () => SGOSLoadingToast.dismissLoading());}
}

按理来说这个GetxController类是用来访问网络的类，这里用来和原生交互，就这样子。

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