harmony 鸿蒙监听组件事件

2025-06-16 浏览 (1)

监听组件事件

NDK接口针对UI组件的事件,提供了监听函数的方式。首先,可使用addNodeEventReceiver函数添加组件事件的监听器,该监听器会监听该组件上发生的所有事件,例如:点击事件、焦点事件。然后,可使用registerNodeEvent函数声明组件的哪些事件需要监听,NDK接口支持的事件范围通过ArkUI_NodeEventType枚举值定义。

说明:

以下示例基于接入ArkTS页面章节,补充相关事件监听。

  • 事件注册和事件解注册

    通过addNodeEventReceiver对节点绑定事件处理函数,接着通过调用registerNodeEvent注册对应的事件。

    说明:

    事件监听函数的入参ArkUI_NodeEvent* event的生命周期只在函数回调周期内生效,不推荐对该指针进行缓存或者进行异步处理。

    ArkUI_NativeNodeAPI_1 *nodeAPI = nullptr;
    OH_ArkUI_GetModuleInterface(ARKUI_NATIVE_NODE, ArkUI_NativeNodeAPI_1, nodeAPI);
    void NodeEventReceiver(ArkUI_NodeEvent *event) {
      // 设置对应的事件类型触发时进行的操作,如NODE_ON_CLICK
    };
    auto button = nodeAPI->createNode(ARKUI_NODE_BUTTON);
    nodeAPI->addNodeEventReceiver(button, NodeEventReceiver);
    nodeAPI->registerNodeEvent(button, NODE_ON_CLICK, 0, nullptr);
    

    详细的事件类型请参考ArkUI_NodeEventType

    通过unregisterNodeEvent解注册对应的事件类型,再通过removeNodeEventReceiver卸载事件处理函数。

    nodeAPI->unregisterNodeEvent(button, NODE_ON_CLICK);
    nodeAPI->removeNodeEventReceiver(button, NodeEventReceiver);
    
  • 全局事件监听

    使用registerNodeEventReceiver注册全局的事件处理函数,对事件进行统一的处理,结束后可使用ungisterNodeEventReceiver进行释放。

    nodeAPI->registerNodeEventReceiver([](ArkUI_NodeEvent *event){
      auto *inputEvent = OH_ArkUI_NodeEvent_GetInputEvent(event);
      auto eventType = OH_ArkUI_NodeEvent_GetEventType(event);
      case NODE_ON_CLICK: {
          // 触发点击事件所进行的操作
      }
      default: {
          break;
      }
    })
    nodeAPI->unregisterNodeEventReceiver();
    
  • 获取事件信息

    ArkUI框架提供了OH_ArkUI_NodeEvent_GetInputEvent()接口,用于从输入交互相关的组件事件(如NODE_ON_CLICK、NODE_TOUCH_EVENT等,具体可参见每个枚举定义的说明)中获取基础事件对象。然后,可通过调用OH_ArkUI_PointerEvent_GetDisplayX()OH_ArkUI_PointerEvent_GetDisplayXByIndex()OH_ArkUI_UIInputEvent_GetAction()OH_ArkUI_UIInputEvent_GetEventTime()等接口,从基础事件中获取更多信息。应用根据获取的事件信息,在事件执行过程中实现差异化交互逻辑。

    // 注册click事件
    nodeAPI->registerNodeEvent(button, NODE_ON_CLICK, 0, nullptr);
    // 设置组件事件的全局监听
    nodeAPI->registerNodeEventReceiver([](ArkUI_NodeEvent *event) {
        // 从组件事件中获取基础事件对象
        auto *inputEvent = OH_ArkUI_NodeEvent_GetInputEvent(event);
        // 从组件事件获取事件类型
        auto eventType = OH_ArkUI_NodeEvent_GetEventType(event);
        OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "inputEvent = %{public}p", inputEvent);
        OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "eventType = %{public}d", eventType);
        auto componentEvent = OH_ArkUI_NodeEvent_GetNodeComponentEvent(event);
        // 获取组件事件中的数字类型数据
        OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "componentEvent = %{public}p",
                      componentEvent);
        // 获取触发该事件的组件对象
        auto nodeHandle = OH_ArkUI_NodeEvent_GetNodeHandle(event);
        OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "nodeHandle = %{public}p", nodeHandle);
        // 根据eventType来区分事件类型,进行差异化处理,其他获取事件信息的接口也可类似方式来进行差异化的处理
        switch (eventType) {
        case NODE_ON_CLICK: {
            // 触发点击事件所进行的操作,从基础事件获取事件信息
            auto x = OH_ArkUI_PointerEvent_GetX(inputEvent);
            auto y = OH_ArkUI_PointerEvent_GetY(inputEvent);
            auto displayX = OH_ArkUI_PointerEvent_GetDisplayX(inputEvent);
            auto displayY = OH_ArkUI_PointerEvent_GetDisplayY(inputEvent);
            auto windowX = OH_ArkUI_PointerEvent_GetWindowX(inputEvent);
            auto windowY = OH_ArkUI_PointerEvent_GetWindowY(inputEvent);
            auto pointerCount = OH_ArkUI_PointerEvent_GetPointerCount(inputEvent);
            auto xByIndex = OH_ArkUI_PointerEvent_GetXByIndex(inputEvent, 0);
            auto yByIndex = OH_ArkUI_PointerEvent_GetYByIndex(inputEvent, 0);
            auto displayXByIndex = OH_ArkUI_PointerEvent_GetDisplayXByIndex(inputEvent, 0);
            auto displayYByIndex = OH_ArkUI_PointerEvent_GetDisplayYByIndex(inputEvent, 0);
            auto windowXByIndex = OH_ArkUI_PointerEvent_GetWindowXByIndex(inputEvent, 0);
            auto windowYByIndex = OH_ArkUI_PointerEvent_GetWindowYByIndex(inputEvent, 0);
            auto pointerId = OH_ArkUI_PointerEvent_GetPointerId(inputEvent, 0);
            auto pressure = OH_ArkUI_PointerEvent_GetPressure(inputEvent, 0);
            auto action = OH_ArkUI_UIInputEvent_GetAction(inputEvent);
            auto eventTime = OH_ArkUI_UIInputEvent_GetEventTime(inputEvent);
            auto sourceType = OH_ArkUI_UIInputEvent_GetSourceType(inputEvent);
            auto type = OH_ArkUI_UIInputEvent_GetType(inputEvent);
            std::string eventInfo =
                "x: " + std::to_string(x) + ", y: " + std::to_string(y) +
                ", displayX: " + std::to_string(displayX) + ", displayY: " + std::to_string(displayY) +
                ", windowX: " + std::to_string(windowX) + ", windowY: " + std::to_string(windowY) +
                ", pointerCount: " + std::to_string(pointerCount) + ", xByIndex: " + std::to_string(xByIndex) +
                ", yByIndex: " + std::to_string(yByIndex) +
                ", displayXByIndex: " + std::to_string(displayXByIndex) +
                ", displayYByIndex: " + std::to_string(displayYByIndex) +
                ", windowXByIndex: " + std::to_string(windowXByIndex) +
                ", windowYByIndex: " + std::to_string(windowYByIndex) +
                ", pointerId: " + std::to_string(pointerId) + ", pressure: " + std::to_string(pressure) +
                ", action: " + std::to_string(action) + ", eventTime: " + std::to_string(eventTime) +
                ", sourceType: " + std::to_string(sourceType) + ", type: " + std::to_string(type);
            OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfoOfCommonEvent", "eventInfo = %{public}s",
                         eventInfo.c_str());
        }
        default: {
            break;
        }
        }
    });
    nodeAPI->unregisterNodeEventReceiver();
    nodeAPI->unregisterNodeEvent(button, NODE_ON_CLICK);
    

完整示例:

  1. 在ArkUINode基类对象中实现通用事件注册逻辑。

    // ArkUINode.h
    // 提供通用属性和事件的封装。
    
    #ifndef MYAPPLICATION_ARKUINODE_H
    #define MYAPPLICATION_ARKUINODE_H
    
    #include "ArkUIBaseNode.h"
    #include "NativeModule.h"
    
    #include <arkui/native_node.h>
    #include <arkui/native_type.h>
    
    namespace NativeModule {
    
    class ArkUINode : public ArkUIBaseNode {
    public:
        explicit ArkUINode(ArkUI_NodeHandle handle) : ArkUIBaseNode(handle) {
            nativeModule_ = NativeModuleInstance::GetInstance()->GetNativeNodeAPI();
            // 事件触发时需要通过函数获取对应的事件对象,这边通过设置节点自定义数据将封装类指针保持在组件上,方便后续事件分发。
            nativeModule_->setUserData(handle_, this);
            // 注册节点监听事件接受器。
            nativeModule_->addNodeEventReceiver(handle_, ArkUINode::NodeEventReceiver);
        }
    
        ~ArkUINode() override {
            if (onClick_) {
                nativeModule_->unregisterNodeEvent(handle_, NODE_ON_CLICK);
            }
            if (onTouch_) {
                nativeModule_->unregisterNodeEvent(handle_, NODE_TOUCH_EVENT);
            }
            if (onDisappear_) {
                nativeModule_->unregisterNodeEvent(handle_, NODE_EVENT_ON_DISAPPEAR);
            }
            if (onAppear_) {
                nativeModule_->unregisterNodeEvent(handle_, NODE_EVENT_ON_APPEAR);
            }
            nativeModule_->removeNodeEventReceiver(handle_, ArkUINode::NodeEventReceiver);
        }
    
        void SetWidth(float width) {
            assert(handle_);
            ArkUI_NumberValue value[] = {{.f32 = width}};
            ArkUI_AttributeItem item = {value, 1};
            nativeModule_->setAttribute(handle_, NODE_WIDTH, &item);
        }
        void SetPercentWidth(float percent) {
            assert(handle_);
            ArkUI_NumberValue value[] = {{.f32 = percent}};
            ArkUI_AttributeItem item = {value, 1};
            nativeModule_->setAttribute(handle_, NODE_WIDTH_PERCENT, &item);
        }
        void SetHeight(float height) {
            assert(handle_);
            ArkUI_NumberValue value[] = {{.f32 = height}};
            ArkUI_AttributeItem item = {value, 1};
            nativeModule_->setAttribute(handle_, NODE_HEIGHT, &item);
        }
        void SetPercentHeight(float percent) {
            assert(handle_);
            ArkUI_NumberValue value[] = {{.f32 = percent}};
            ArkUI_AttributeItem item = {value, 1};
            nativeModule_->setAttribute(handle_, NODE_HEIGHT_PERCENT, &item);
        }
        void SetBackgroundColor(uint32_t color) {
            assert(handle_);
            ArkUI_NumberValue value[] = {{.u32 = color}};
            ArkUI_AttributeItem item = {value, 1};
            nativeModule_->setAttribute(handle_, NODE_BACKGROUND_COLOR, &item);
        }
        // 处理通用事件。
        void RegisterOnClick(const std::function<void()> &onClick) {
            assert(handle_);
            onClick_ = onClick;
            // 注册点击事件。
            nativeModule_->registerNodeEvent(handle_, NODE_ON_CLICK, 0, nullptr);
        }
    
        void RegisterOnTouch(const std::function<void(int32_t type, float x, float y)> &onTouch) {
            assert(handle_);
            onTouch_ = onTouch;
            // 注册触碰事件。
            nativeModule_->registerNodeEvent(handle_, NODE_TOUCH_EVENT, 0, nullptr);
        }
    
        void RegisterOnDisappear(const std::function<void()> &onDisappear) {
            assert(handle_);
            onDisappear_ = onDisappear;
            // 注册卸载事件。
            nativeModule_->registerNodeEvent(handle_, NODE_EVENT_ON_DISAPPEAR, 0, nullptr);
        }
    
        void RegisterOnAppear(const std::function<void()> &onAppear) {
            assert(handle_);
            onAppear_ = onAppear;
            // 注册挂载事件。
            nativeModule_->registerNodeEvent(handle_, NODE_EVENT_ON_APPEAR, 0, nullptr);
        }
    
    protected:
        // 事件监听器函数指针。
        static void NodeEventReceiver(ArkUI_NodeEvent *event) {
            // 获取事件发生的UI组件对象。
            auto nodeHandle = OH_ArkUI_NodeEvent_GetNodeHandle(event);
            // 获取保持在UI组件对象中的自定义数据,返回封装类指针。
            auto *node = reinterpret_cast<ArkUINode *>(
                NativeModuleInstance::GetInstance()->GetNativeNodeAPI()->getUserData(nodeHandle));
            // 基于封装类实例对象处理事件。
            node->ProcessNodeEvent(event);
        }
        void ProcessNodeEvent(ArkUI_NodeEvent *event) {
            auto eventType = OH_ArkUI_NodeEvent_GetEventType(event);
            switch (eventType) {
            case NODE_ON_CLICK: {
                if (onClick_) {
                    onClick_();
                }
                break;
            }
            case NODE_TOUCH_EVENT: {
                if (onTouch_) {
                    auto *uiInputEvent = OH_ArkUI_NodeEvent_GetInputEvent(event);
                    float x = OH_ArkUI_PointerEvent_GetX(uiInputEvent);
                    float y = OH_ArkUI_PointerEvent_GetY(uiInputEvent);
                    auto type = OH_ArkUI_UIInputEvent_GetAction(uiInputEvent);
                    onTouch_(type, x, y);
                }
            }
            case NODE_EVENT_ON_DISAPPEAR: {
                if (onDisappear_) {
                    onDisappear_();
                }
                break;
            }
            case NODE_EVENT_ON_APPEAR: {
                if (onAppear_) {
                    onAppear_();
                }
                break;
            }
            default: {
                // 组件特有事件交给子类处理
                OnNodeEvent(event);
            }
            }
        }
    
        virtual void OnNodeEvent(ArkUI_NodeEvent *event) {}
    
        void OnAddChild(const std::shared_ptr<ArkUIBaseNode> &child) override {
            nativeModule_->addChild(handle_, child->GetHandle());
        }
    
        void OnRemoveChild(const std::shared_ptr<ArkUIBaseNode> &child) override {
            nativeModule_->removeChild(handle_, child->GetHandle());
        }
    
        void OnInsertChild(const std::shared_ptr<ArkUIBaseNode> &child, int32_t index) override {
            nativeModule_->insertChildAt(handle_, child->GetHandle(), index);
        }
    
    private:
        std::function<void()> onClick_;
        std::function<void()> onDisappear_;
        std::function<void()> onAppear_;
        std::function<void(int32_t type, float x, float y)> onTouch_;
    };
    } // namespace NativeModule
    
    #endif // MYAPPLICATION_ARKUINODE_H
    
    
  2. 在ArkUIListNode对象中实现列表事件注册逻辑。

    // ArkUIListNode.h
    // 列表封装类对象
    
    #ifndef MYAPPLICATION_ARKUILISTNODE_H
    #define MYAPPLICATION_ARKUILISTNODE_H
    
    #include "ArkUINode.h"
    #include <hilog/log.h>
    
    namespace NativeModule {
    class ArkUIListNode : public ArkUINode {
    public:
        ArkUIListNode()
            : ArkUINode((NativeModuleInstance::GetInstance()->GetNativeNodeAPI())->createNode(ARKUI_NODE_LIST)) {}
    
        ~ArkUIListNode() override { nativeModule_->unregisterNodeEvent(handle_, NODE_LIST_ON_SCROLL_INDEX); }
    
        void SetScrollBarState(bool isShow) {
            assert(handle_);
            ArkUI_ScrollBarDisplayMode displayMode =
                isShow ? ARKUI_SCROLL_BAR_DISPLAY_MODE_ON : ARKUI_SCROLL_BAR_DISPLAY_MODE_OFF;
            ArkUI_NumberValue value[] = {{.i32 = displayMode}};
            ArkUI_AttributeItem item = {value, 1};
            nativeModule_->setAttribute(handle_, NODE_SCROLL_BAR_DISPLAY_MODE, &item);
        }
    
        // 注册列表相关事件。
        void RegisterOnScrollIndex(const std::function<void(int32_t index)> &onScrollIndex) {
            assert(handle_);
            onScrollIndex_ = onScrollIndex;
            nativeModule_->registerNodeEvent(handle_, NODE_LIST_ON_SCROLL_INDEX, 0, nullptr);
        }
    
    protected:
       // 处理List相关事件。
        void OnNodeEvent(ArkUI_NodeEvent *event) override {
            auto eventType = OH_ArkUI_NodeEvent_GetEventType(event);
            switch (eventType) {
            case NODE_LIST_ON_SCROLL_INDEX: {
                auto index = OH_ArkUI_NodeEvent_GetNodeComponentEvent(event)->data[0];
                if (onScrollIndex_) {
                    onScrollIndex_(index.i32);
                }
            }
            default: {
            }
            }
        }
    
    private:
        std::function<void(int32_t index)> onScrollIndex_;
    };
    } // namespace NativeModule
    
    #endif // MYAPPLICATION_ARKUILISTNODE_H
    
  3. 添加相关事件。

    // TextListExample.h
    // 文本列表示例。
    
    #ifndef MYAPPLICATION_NORMALTEXTLISTEXAMPLE_H
    #define MYAPPLICATION_NORMALTEXTLISTEXAMPLE_H
    
    #include "ArkUIBaseNode.h"
    #include "ArkUIListItemNode.h"
    #include "ArkUIListNode.h"
    #include "ArkUITextNode.h"
    #include <hilog/log.h>
    
    namespace NativeModule {
    
    std::shared_ptr<ArkUIBaseNode> CreateTextListExample() {
        // 创建组件并挂载
        // 1:创建List组件。
        auto list = std::make_shared<ArkUIListNode>();
        list->SetPercentWidth(1);
        list->SetPercentHeight(1);
        // 2:创建ListItem子组件并挂载到List上。
        for (int32_t i = 0; i < 30; ++i) {
            auto listItem = std::make_shared<ArkUIListItemNode>();
            auto textNode = std::make_shared<ArkUITextNode>();
            textNode->SetTextContent(std::to_string(i));
            textNode->SetFontSize(16);
            textNode->SetPercentWidth(1);
            textNode->SetHeight(100);
            textNode->SetBackgroundColor(0xFFfffacd);
            textNode->SetTextAlign(ARKUI_TEXT_ALIGNMENT_CENTER);
            listItem->AddChild(textNode);
            // 列表项注册点击事件。
            auto onClick = [](ArkUI_NodeEvent *event) {
                // 从组件事件中获取基础事件对象
                auto *inputEvent = OH_ArkUI_NodeEvent_GetInputEvent(event);
                // 从组件事件获取事件类型
                auto eventType = OH_ArkUI_NodeEvent_GetEventType(event);
                OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "inputEvent = %{public}p", inputEvent);
                OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "eventType = %{public}d", eventType);
                auto componentEvent = OH_ArkUI_NodeEvent_GetNodeComponentEvent(event);
                // 获取组件事件中的数字类型数据
                OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "componentEvent = %{public}p",
                             componentEvent);
                // 获取触发该事件的组件对象
                auto nodeHandle = OH_ArkUI_NodeEvent_GetNodeHandle(event);
                OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfo", "nodeHandle = %{public}p", nodeHandle);
                // 根据eventType来区分事件类型,进行差异化处理,其他获取事件信息的接口也可类似方式来进行差异化的处理
                switch (eventType) {
                case NODE_ON_CLICK: {
                    // 触发点击事件所进行的操作,从基础事件获取事件信息
                    auto x = OH_ArkUI_PointerEvent_GetX(inputEvent);
                    auto y = OH_ArkUI_PointerEvent_GetY(inputEvent);
                    auto displayX = OH_ArkUI_PointerEvent_GetDisplayX(inputEvent);
                    auto displayY = OH_ArkUI_PointerEvent_GetDisplayY(inputEvent);
                    auto windowX = OH_ArkUI_PointerEvent_GetWindowX(inputEvent);
                    auto windowY = OH_ArkUI_PointerEvent_GetWindowY(inputEvent);
                    auto pointerCount = OH_ArkUI_PointerEvent_GetPointerCount(inputEvent);
                    auto xByIndex = OH_ArkUI_PointerEvent_GetXByIndex(inputEvent, 0);
                    auto yByIndex = OH_ArkUI_PointerEvent_GetYByIndex(inputEvent, 0);
                    auto displayXByIndex = OH_ArkUI_PointerEvent_GetDisplayXByIndex(inputEvent, 0);
                    auto displayYByIndex = OH_ArkUI_PointerEvent_GetDisplayYByIndex(inputEvent, 0);
                    auto windowXByIndex = OH_ArkUI_PointerEvent_GetWindowXByIndex(inputEvent, 0);
                    auto windowYByIndex = OH_ArkUI_PointerEvent_GetWindowYByIndex(inputEvent, 0);
                    auto pointerId = OH_ArkUI_PointerEvent_GetPointerId(inputEvent, 0);
                    auto pressure = OH_ArkUI_PointerEvent_GetPressure(inputEvent, 0);
                    auto action = OH_ArkUI_UIInputEvent_GetAction(inputEvent);
                    auto eventTime = OH_ArkUI_UIInputEvent_GetEventTime(inputEvent);
                    auto sourceType = OH_ArkUI_UIInputEvent_GetSourceType(inputEvent);
                    auto type = OH_ArkUI_UIInputEvent_GetType(inputEvent);
                    std::string eventInfo =
                        "x: " + std::to_string(x) + ", y: " + std::to_string(y) +
                        ", displayX: " + std::to_string(displayX) + ", displayY: " + std::to_string(displayY) +
                        ", windowX: " + std::to_string(windowX) + ", windowY: " + std::to_string(windowY) +
                        ", pointerCount: " + std::to_string(pointerCount) + ", xByIndex: " + std::to_string(xByIndex) +
                        ", yByIndex: " + std::to_string(yByIndex) +
                        ", displayXByIndex: " + std::to_string(displayXByIndex) +
                        ", displayYByIndex: " + std::to_string(displayYByIndex) +
                        ", windowXByIndex: " + std::to_string(windowXByIndex) +
                        ", windowYByIndex: " + std::to_string(windowYByIndex) +
                        ", pointerId: " + std::to_string(pointerId) + ", pressure: " + std::to_string(pressure) +
                        ", action: " + std::to_string(action) + ", eventTime: " + std::to_string(eventTime) +
                        ", sourceType: " + std::to_string(sourceType) + ", type: " + std::to_string(type);
                    OH_LOG_Print(LOG_APP, LOG_INFO, LOG_PRINT_DOMAIN, "eventInfoOfCommonEvent",
                                 "eventInfo = %{public}s", eventInfo.c_str());
                }
                default: {
                    break;
                }
                }
            };
            listItem->RegisterOnClick(onClick);
            list->AddChild(listItem);
        }
        // 3:注册List相关监听事件.
        list->RegisterOnScrollIndex([](int32_t index) { OH_LOG_INFO(LOG_APP, "on list scroll index: %{public}d", index); });
        // 4: 注册挂载事件。
        list->RegisterOnAppear([]() { OH_LOG_INFO(LOG_APP, "on list mount to tree"); });
        // 4: 注册卸载事件。
        list->RegisterOnDisappear([]() { OH_LOG_INFO(LOG_APP, "on list unmount from tree"); });
        return list;
    }
    } // namespace NativeModule
    
    #endif // MYAPPLICATION_NORMALTEXTLISTEXAMPLE_H
    
    

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