#鸿蒙通关秘籍#如何使用NativeWindowEventFilter过滤多模输入事件？

为了在特定窗口中拦截按键事件，可以使用NativeWindowEventFilter模块，具体步骤如下：

1. 在CMake脚本中链接必要的动态库：

   bash target_link_libraries(entry PUBLIC libnative_window_manager.so libohinput.so)

2. 添加头文件：

   cpp #include "window_manager/oh_window_comm.h" #include "window_manager/oh_window_event_filter.h" #include "multimodalinput/oh_input_manager.h" #include "multimodalinput/oh_key_code.h"

3. 注册和取消按键事件过滤函数，可以通过如下代码实现按键过滤：

   cpp #include "napi/native_api.h" #include "window_manager/oh_window_comm.h" #include "window_manager/oh_window_event_filter.h" #include "multimodalinput/oh_input_manager.h" #include "multimodalinput/oh_key_code.h"

   static bool filterFunc(Input_KeyEvent *event) { auto keyCode = OH_Input_GetKeyEventKeyCode(event); auto action = OH_Input_GetKeyEventAction(event); return (keyCode >= Input_KeyCode::KEYCODE_0 && keyCode <= Input_KeyCode::KEYCODE_9 && action == Input_KeyEventAction::KEY_ACTION_DOWN) || (keyCode == Input_KeyCode::KEYCODE_ESCAPE); }

   static napi_value registerFilter(napi_env env, napi_callback_info info) { size_t argc = 1; napi_value args[1] = {nullptr}; napi_get_cb_info(env, info, &argc, args, nullptr, nullptr);

   int32_t windowId; napi_get_value_int32(env, args[0], &windowId);

   auto res = OH_NativeWindowManager_RegisterKeyEventFilter(windowId, filterFunc); napi_value errCode; napi_create_int32(env, res, &errCode); return errCode; }

   static napi_value clearFilter(napi_env env, napi_callback_info info) { size_t argc = 1; napi_value args[1] = {nullptr}; napi_get_cb_info(env, info, &argc, args, nullptr, nullptr);

   int32_t windowId; napi_get_value_int32(env, args[0], &windowId);

   auto res = OH_NativeWindowManager_UnregisterKeyEventFilter(windowId); napi_value errCode; napi_create_int32(env, res, &errCode); return errCode; }

   EXTERN_C_START static napi_value Init(napi_env env, napi_value exports) { napi_property_descriptor desc[] = { {"registerFilter", nullptr, registerFilter, nullptr, nullptr, nullptr, napi_default, nullptr}, {"clearFilter", nullptr, clearFilter, nullptr, nullptr, nullptr, napi_default, nullptr}}; napi_define_properties(env, exports, sizeof(desc) / sizeof(desc[0]), desc); return exports; } EXTERN_C_END