场景介绍
通过napi_wrap将ArkTS对象与Native的C++对象绑定，后续操作时再通过napi_unwrap将ArkTS对象绑定的C++对象取出，并对其进行操作。
使用示例
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接口声明、编译配置以及模块注册
接口声明
// index.d.ts export class MyObject { constructor(arg: number); plusOne: () => number; public get value(); public set value(newVal: number); }编译配置
// CMakeLists.txt # the minimum version of CMake. cmake_minimum_required(VERSION 3.4.1) project(object_wrap) set(NATIVERENDER_ROOT_PATH ${CMAKE_CURRENT_SOURCE_DIR}) include_directories(${NATIVERENDER_ROOT_PATH} ${NATIVERENDER_ROOT_PATH}/include) add_definitions("-DLOG_DOMAIN=0x0000") add_definitions("-DLOG_TAG=\"testTag\"") add_library(object_wrap SHARED object_wrap.cpp) target_link_libraries(object_wrap PUBLIC libace_napi.z.so libhilog_ndk.z.so)模块注册
// object_wrap.cpp class MyObject { public: static napi_value Init(napi_env env, napi_value exports); static void Destructor(napi_env env, void* nativeObject, void* finalize_hint); private: explicit MyObject(double value_ = 0); ~MyObject(); static napi_value New(napi_env env, napi_callback_info info); static napi_value GetValue(napi_env env, napi_callback_info info); static napi_value SetValue(napi_env env, napi_callback_info info); static napi_value PlusOne(napi_env env, napi_callback_info info); double value_; napi_env env_; napi_ref wrapper_; }; static thread_local napi_ref g_ref = nullptr; MyObject::MyObject(double value) : value_(value), env_(nullptr), wrapper_(nullptr) {} MyObject::~MyObject() { napi_delete_reference(env_, wrapper_); } void MyObject::Destructor(napi_env env, void* nativeObject, [[maybe_unused]] void* finalize_hint) { OH_LOG_INFO(LOG_APP, "MyObject::Destructor called"); reinterpret_cast<MyObject*>(nativeObject)->~MyObject(); } napi_value MyObject::Init(napi_env env, napi_value exports) { napi_property_descriptor properties[] = { {"value", 0, 0, GetValue, SetValue, 0, napi_default, 0}, { "plusOne", nullptr, PlusOne, nullptr, nullptr, nullptr, napi_default, nullptr } }; napi_value cons; assert(napi_define_class(env, "MyObject", NAPI_AUTO_LENGTH, New, nullptr, 2, properties, &cons) == napi_ok); assert(napi_create_reference(env, cons, 1, &g_ref) == napi_ok); assert(napi_set_named_property(env, exports, "MyObject", cons) == napi_ok); return exports; } EXTERN_C_START static napi_value Init(napi_env env, napi_value exports) { MyObject::Init(env, exports); return exports; } EXTERN_C_END static napi_module nativeModule = { .nm_version = 1, .nm_flags = 0, .nm_filename = nullptr, .nm_register_func = Init, .nm_modname = "object_wrap", .nm_priv = nullptr, .reserved = { 0 }, }; extern "C" __attribute__((constructor)) void RegisterObjectWrapModule() { napi_module_register(&nativeModule); } -
在构造函数中绑定ArkJS与C++对象
napi_value MyObject::New(napi_env env, napi_callback_info info) { OH_LOG_INFO(LOG_APP, "MyObject::New called"); napi_value newTarget; assert(napi_get_new_target(env, info, &newTarget) == napi_ok); if (newTarget != nullptr) { // 使用`new MyObject(...)`调用方式 size_t argc = 1; napi_value args[1]; napi_value jsThis; assert(napi_get_cb_info(env, info, &argc, args, &jsThis, nullptr) == napi_ok); double value = 0.0; napi_valuetype valuetype; assert(napi_typeof(env, args[0], &valuetype) == napi_ok); if (valuetype != napi_undefined) { assert(napi_get_value_double(env, args[0], &value) == napi_ok); } MyObject* obj = new MyObject(value); obj->env_ = env; // 通过napi_wrap将ArkTS对象jsThis与C++对象obj绑定 assert(napi_wrap(env, jsThis, reinterpret_cast<void*>(obj), MyObject::Destructor, nullptr, // finalize_hint &obj->wrapper_) == napi_ok); return jsThis; } else { // 使用`MyObject(...)`调用方式 size_t argc = 1; napi_value args[1]; assert(napi_get_cb_info(env, info, &argc, args, nullptr, nullptr) == napi_ok && argc == 1); napi_value cons; assert(napi_get_reference_value(env, g_ref, &cons) == napi_ok); napi_value instance; assert(napi_new_instance(env, cons, argc, args, &instance) == napi_ok); return instance; } } -
将ArkTS对象之前绑定的C++对象取出，并对其进行操作
napi_value MyObject::GetValue(napi_env env, napi_callback_info info) { OH_LOG_INFO(LOG_APP, "MyObject::GetValue called"); napi_value jsThis; assert(napi_get_cb_info(env, info, nullptr, nullptr, &jsThis, nullptr) == napi_ok); MyObject* obj; // 通过napi_unwrap将jsThis之前绑定的C++对象取出，并对其进行操作 assert(napi_unwrap(env, jsThis, reinterpret_cast<void**>(&obj)) == napi_ok); napi_value num; assert(napi_create_double(env, obj->value_, &num) == napi_ok); return num; } napi_value MyObject::SetValue(napi_env env, napi_callback_info info) { OH_LOG_INFO(LOG_APP, "MyObject::SetValue called"); size_t argc = 1; napi_value value; napi_value jsThis; assert(napi_get_cb_info(env, info, &argc, &value, &jsThis, nullptr) == napi_ok); MyObject* obj; // 通过napi_unwrap将jsThis之前绑定的C++对象取出，并对其进行操作 assert(napi_unwrap(env, jsThis, reinterpret_cast<void**>(&obj)) == napi_ok); assert(napi_get_value_double(env, value, &obj->value_) == napi_ok); return nullptr; } napi_value MyObject::PlusOne(napi_env env, napi_callback_info info) { OH_LOG_INFO(LOG_APP, "MyObject::PlusOne called"); napi_value jsThis; assert(napi_get_cb_info(env, info, nullptr, nullptr, &jsThis, nullptr) == napi_ok); MyObject* obj; // 通过napi_unwrap将jsThis之前绑定的C++对象取出，并对其进行操作 assert(napi_unwrap(env, jsThis, reinterpret_cast<void**>(&obj)) == napi_ok); obj->value_ += 1; napi_value num; assert(napi_create_double(env, obj->value_, &num) == napi_ok); return num; } -
ArkTS侧示例代码
import hilog from '@ohos.hilog'; import { MyObject } from 'libobject_wrap.so' let object : MyObject = new MyObject(0); object.value = 1023; hilog.info(0x0000, 'testTag', 'MyObject value after set: %{public}d', object.value); hilog.info(0x0000, 'testTag', 'MyObject plusOne: %{public}d', object.plusOne());