#鸿蒙通关秘籍#如何在非ArkTS线程中回调ArkTS接口？

要在非ArkTS线程中回调ArkTS接口，可以利用napi_get_uv_event_loop和uv_queue_work实现。具体步骤包括：

1. 接口声明：为要实现的接口定义类型签名，例如：

   bash // index.d.ts export const queueWork: (cb: (arg: number) => void) => void;

2. 编译配置：设置CMake编译配置，将必要的库链接到项目中。

   bash // CMakeLists.txt cmake_minimum_required(VERSION 3.4.1) project(MyApplication)

   set(NATIVERENDER_ROOT_PATH ${CMAKE_CURRENT_SOURCE_DIR})

   include_directories(${NATIVERENDER_ROOT_PATH} ${NATIVERENDER_ROOT_PATH}/include) add_library(queue_work SHARED queue_work.cpp) target_link_libraries(queue_work PUBLIC libace_napi.z.so libhilog_ndk.z.so libuv.so)

3. 模块注册：在C++中注册模块并定义导出的接口。

   cpp // queue_work.cpp EXTERN_C_START static napi_value Init(napi_env env, napi_value exports) { napi_property_descriptor desc[] = { { "queueWork", nullptr, QueueWork, nullptr, nullptr, nullptr, napi_default, nullptr } }; napi_define_properties(env, exports, sizeof(desc) / sizeof(desc[0]), desc); return exports; } EXTERN_C_END

   static napi_module nativeModule = { .nm_version = 1, .nm_flags = 0, .nm_filename = nullptr, .nm_register_func = Init, .nm_modname = "queue_work", .nm_priv = nullptr, .reserved = { 0 }, };

   extern "C" attribute((constructor)) void RegisterQueueWorkModule() { napi_module_register(&nativeModule); }

4. 线程操作：定义处理异步任务和回调ArkTS的核心逻辑。

   cpp // queue_work.cpp #include <thread> #include "napi/native_api.h" #include "uv.h"

   struct CallbackContext { napi_env env = nullptr; napi_ref callbackRef = nullptr; int32_t retData = 0; };

   void StartThread(CallbackContext* context) { uv_loop_s* loop = nullptr; napi_get_uv_event_loop(context->env, &loop);

    uv_work_t* work = new uv_work_t;
    context->retData = 1;
    work->data = context;
   
    uv_queue_work(
        loop,
        work,
        [](uv_work_t* work) {},
        [](uv_work_t* work, int status) {
            CallbackContext* context = reinterpret_cast<CallbackContext*>(work->data);
            napi_handle_scope scope = nullptr;
            napi_open_handle_scope(context->env, &scope);
            if (scope == nullptr) {
                return;
            }
   
            napi_value callback = nullptr;
            napi_get_reference_value(context->env, context->callbackRef, &callback);
            napi_value retArg;
            napi_create_int32(context->env, context->retData, &retArg);
            napi_value ret;
            napi_call_function(context->env, nullptr, callback, 1, &retArg, &ret);
            napi_delete_reference(context->env, context->callbackRef);
            napi_close_handle_scope(context->env, scope);
   
            if (work != nullptr) {
                delete work;
            }
            delete context;
        }
    );
   

   }

   static napi_value QueueWork(napi_env env, napi_callback_info info) { size_t argc = 1; napi_value argv[1] = {nullptr}; napi_value thisVar = nullptr; void *data = nullptr; napi_get_cb_info(env, info, &argc, argv, &thisVar, &data);

    if (argc < 1) {
        napi_throw_error(env, "ParameterError", "one param expected");
        return nullptr;
    }
    napi_valuetype valueType = napi_undefined;
    napi_typeof(env, argv[0], &valueType);
    if (valueType != napi_function) {
        napi_throw_error(env, "ParameterError", "function expected");
        return nullptr;
    }
   
    auto asyncContext = new CallbackContext();
    asyncContext->env = env;
    napi_create_reference(env, argv[0], 1, &asyncContext->callbackRef);
    std::thread testThread(StartThread, asyncContext);
    testThread.detach();
   
    return nullptr;
   

   }

5. ArkTS调用示例：在ArkTS中使用该接口。

   typescript import { queueWork } from 'libqueue_work.so'

   queueWork((result: number) => { console.log("result = " + result); });