【HarmonyOS 5】鸿蒙跨平台开发方案详解（二）

import 'package:flutter/services.dart';
class HarmonyKit {  static const MethodChannel _channel =      MethodChannel('com.example/harmony_kit');
  // 示例：调用鸿蒙的Toast  static Future<String?> showToast(String message) async {    try {      return await _channel.invokeMethod('showToast', {'message': message});    } on PlatformException catch (e) {      return '错误: ${e.message}';    }  }
}

// index.etsimport common from '@ohos.app.ability.common';import promptAction from '@ohos.promptAction';import mediaLibrary from '@ohos.multimedia.mediaLibrary';import { BusinessError } from '@ohos.base';
@Entry@Componentstruct Index {  private context = getContext(this) as common.UIAbilityContext;  private flutterChannel: any = null;
  aboutToAppear() {    this.initFlutterChannel();  }
  // 初始化Flutter通信通道  initFlutterChannel() {    // 创建与Flutter通信的通道    this.flutterChannel = new FlutterMethodChannel(      this.context,       'com.example/harmony_kit',       StandardMethodCodec.INSTANCE    );
    // 设置方法调用处理器    this.flutterChannel.setMethodCallHandler((call: MethodCall, result: MethodResult) => {      switch (call.method) {        case 'showToast':          this.showHarmonyToast(call.arguments.message);          result.success('Toast已显示');          break;        default:          result.notImplemented();      }    });  }
  // 显示鸿蒙Toast  async showHarmonyToast(message: string) {    try {      await promptAction.showToast({        message: message,        duration: 3000      });    } catch (error) {      console.error(`显示Toast失败: ${(error as BusinessError).message}`);    }  }
  build() {    Column() {      // 鸿蒙界面组件      Text('Flutter与鸿蒙通信示例')        .fontSize(20)        .fontWeight(FontWeight.Bold)        .margin({ top: 50, bottom: 30 })    }    .width('100%')  }}

    Flutter UI → Skia → OHNativeWindow → Vulkan Surface → 硬件加速渲染

  Flutter UI → Impeller → ArkGraphics(Vulkan) → 硬件加速渲染

通过XComponent创建渲染表面使用ArkUI C API将原生组件树附加到OH_NativeXComponentFlutter将其作为PlatformView管理，实现混合布局

graph TDA[Flutter渲染指令] --> B(Skia引擎)B --> C[XComponent获取OHNativeWindow]C --> D[VK_OHOS_surface扩展]D --> E[Vulkan Surface绘制]E --> F[鸿蒙显示系统]