イベントハンドラーを実装する方法

[アーティクル]
06/13/2023

このトピックには、クライアントが Microsoft UI オートメーションイベントを受信して処理できるようにするインターフェイスを実装する方法を示すコード例が含まれています。次のトピックについて説明します。

一般的なUI オートメーションイベントの処理
Focus-Changed イベントの処理
Property-Changed イベントの処理
Structure-Changed イベントの処理
関連トピック

一般的なUI オートメーションイベントの処理

次のコード例は、一般的なUI オートメーションイベントのUI オートメーションイベントハンドラーを実装する Microsoft Windows コンソールアプリケーションです。次の使用例は、ツールヒントやその他のウィンドウの作成イベントと破棄イベントを処理します。

// Defines an event handler for general UI Automation events. It listens for
// tooltip and window creation and destruction events. 
#include <windows.h>
#include <stdio.h>
#include <UIAutomation.h>

class EventHandler:
    public IUIAutomationEventHandler
{
private:
    LONG _refCount;

public:
    int _eventCount;

    // Constructor.
    EventHandler(): _refCount(1), _eventCount(0) 
    {
    }

    // IUnknown methods.
    ULONG STDMETHODCALLTYPE AddRef() 
    {
        ULONG ret = InterlockedIncrement(&_refCount);
        return ret;
    }

    ULONG STDMETHODCALLTYPE Release() 
    {
        ULONG ret = InterlockedDecrement(&_refCount);
        if (ret == 0) 
        {
            delete this;
            return 0;
        }
        return ret;
    }

    HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid, void** ppInterface) 
    {
        if (riid == __uuidof(IUnknown)) 
            *ppInterface=static_cast<IUIAutomationEventHandler*>(this);
        else if (riid == __uuidof(IUIAutomationEventHandler)) 
            *ppInterface=static_cast<IUIAutomationEventHandler*>(this);
        else 
        {
            *ppInterface = NULL;
            return E_NOINTERFACE;
        }
        this->AddRef();
        return S_OK;
    }

    // IUIAutomationEventHandler methods
    HRESULT STDMETHODCALLTYPE HandleAutomationEvent(IUIAutomationElement * pSender, EVENTID eventID)
    {
        _eventCount++;
        switch (eventID) 
        {
            case UIA_ToolTipOpenedEventId:
                wprintf(L">> Event ToolTipOpened Received! (count: %d)\n", _eventCount);
                break;
            case UIA_ToolTipClosedEventId:
                wprintf(L">> Event ToolTipClosed Received! (count: %d)\n", _eventCount);
                break;
            case UIA_Window_WindowOpenedEventId:
                wprintf(L">> Event WindowOpened Received! (count: %d)\n", _eventCount);
                break;
            case UIA_Window_WindowClosedEventId:
                wprintf(L">> Event WindowClosed Received! (count: %d)\n", _eventCount);
                break;
            default:
                wprintf(L">> Event (%d) Received! (count: %d)\n", eventID, _eventCount);
                break;
        }
        return S_OK;
    }
};

int main(int argc, char* argv[])
{
    HRESULT hr;
    int ret = 0;
    IUIAutomationElement* pTargetElement = NULL;
    EventHandler* pEHTemp = NULL;

    CoInitializeEx(NULL,COINIT_MULTITHREADED);
    IUIAutomation* pAutomation = NULL;
    hr = CoCreateInstance(__uuidof(CUIAutomation), NULL,CLSCTX_INPROC_SERVER, __uuidof(IUIAutomation), (void**)&pAutomation);
    if(FAILED(hr) || pAutomation==NULL) 
    {
        ret = 1;
        goto cleanup;
    }
    // Use root element for listening to window and tooltip creation and destruction.
    hr = pAutomation->GetRootElement(&pTargetElement);
    if (FAILED(hr) || pTargetElement==NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    pEHTemp = new EventHandler();
    if (pEHTemp == NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Adding Event Handlers.\n");
    hr = pAutomation->AddAutomationEventHandler(UIA_ToolTipOpenedEventId, pTargetElement, TreeScope_Subtree, NULL, (IUIAutomationEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }
    hr = pAutomation->AddAutomationEventHandler(UIA_ToolTipClosedEventId, pTargetElement, TreeScope_Subtree, NULL, (IUIAutomationEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }
    hr = pAutomation->AddAutomationEventHandler(UIA_Window_WindowOpenedEventId, pTargetElement, TreeScope_Subtree, NULL, (IUIAutomationEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }
    hr = pAutomation->AddAutomationEventHandler(UIA_Window_WindowClosedEventId, pTargetElement, TreeScope_Subtree, NULL, (IUIAutomationEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Press any key to remove event handlers and exit\n");
    getchar();

    wprintf(L"-Removing Event Handlers.\n");

cleanup:
    // Remove event handlers, release resources, and terminate
    if (pAutomation != NULL) 
    {
        hr = pAutomation->RemoveAllEventHandlers();
        if (FAILED(hr))
            ret = 1;
        pAutomation->Release();
    }

    if (pEHTemp != NULL) 
        pEHTemp->Release();

    if (pTargetElement != NULL) 
        pTargetElement->Release();

    CoUninitialize();
    return ret;
}

Focus-Changed イベントの処理

次のコード例は、フォーカス変更イベントのハンドラーを実装する Windows コンソールアプリケーションです。

// Defines an event handler for focus changed events and starts
// listening to them.
#include <windows.h>
#include <stdio.h>
#include <UIAutomation.h>

class EventHandler:
    public IUIAutomationFocusChangedEventHandler
{
private:
    LONG _refCount;

public:
    int _eventCount;

    //Constructor.
    EventHandler(): _refCount(1), _eventCount(0) 
    {
    }

    //IUnknown methods.
    ULONG STDMETHODCALLTYPE AddRef() 
    {
        ULONG ret = InterlockedIncrement(&_refCount);
        return ret;
    }

    ULONG STDMETHODCALLTYPE Release() 
    {
        ULONG ret = InterlockedDecrement(&_refCount);
        if (ret == 0) 
        {
            delete this;
            return 0;
        }
        return ret;
    }

    HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid, void** ppInterface) 
    {
        if (riid == __uuidof(IUnknown))
            *ppInterface = static_cast<IUIAutomationFocusChangedEventHandler*>(this);
        else if(riid == __uuidof(IUIAutomationFocusChangedEventHandler)) 
            *ppInterface=static_cast<IUIAutomationFocusChangedEventHandler*>(this);
        else 
        {
            *ppInterface = NULL;
            return E_NOINTERFACE;
        }
        this->AddRef();
        return S_OK;
    }

    // IUIAutomationFocusChangedEventHandler methods.
    HRESULT STDMETHODCALLTYPE HandleFocusChangedEvent(IUIAutomationElement * pSender) 
    {
        _eventCount++;
        wprintf(L">> FocusChangedEvent Received! (count: %d)\n", _eventCount);
        return S_OK;
    }
};

int main(int argc, char* argv[]) 
{
    HRESULT hr;
    int ret = 0;
    EventHandler* pEHTemp = NULL;

    CoInitializeEx(NULL,COINIT_MULTITHREADED);
    IUIAutomation* pAutomation = NULL;
    hr = CoCreateInstance(__uuidof(CUIAutomation), NULL,CLSCTX_INPROC_SERVER, __uuidof(IUIAutomation), (void**)&pAutomation);
    if (FAILED(hr) || pAutomation == NULL)
    {
        ret = 1;
        goto cleanup;
    }

    pEHTemp = new EventHandler();
    if (pEHTemp == NULL)
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Adding Event Handlers.\n");
    hr = pAutomation->AddFocusChangedEventHandler(NULL, (IUIAutomationFocusChangedEventHandler*) pEHTemp); 
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Press any key to remove event handler and exit\n");
    getchar();

    wprintf(L"-Removing Event Handlers.\n");
    hr = pAutomation->RemoveFocusChangedEventHandler((IUIAutomationFocusChangedEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }

    // Release resources and terminate.
cleanup:
    if (pEHTemp != NULL) 
        pEHTemp->Release();

    if (pAutomation != NULL) 
        pAutomation->Release();

    CoUninitialize();
    return ret;
}

Property-Changed イベントの処理

次のコード例は、プロパティ変更イベントのハンドラーを実装する Windows コンソールアプリケーションです。

// Defines an event handler for property-changed events, and listens for
// ToggleState property changes on the element specifies by the user.
#include <windows.h>
#include <stdio.h>
#include <UIAutomation.h>

class EventHandler:
    public IUIAutomationPropertyChangedEventHandler
{
private:
    LONG _refCount;

public:
    int _eventCount;

    //Constructor.
    EventHandler(): _refCount(1), _eventCount(0) 
    {
    }

    //IUnknown methods.
    ULONG STDMETHODCALLTYPE AddRef() 
    {
        ULONG ret = InterlockedIncrement(&_refCount);
        return ret;
    }

    ULONG STDMETHODCALLTYPE Release() 
    {
        ULONG ret = InterlockedDecrement(&_refCount);
        if (ret == 0) 
        {
            delete this;
            return 0;
        }
        return ret;
    }

    HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid, void** ppInterface) 
    {
        if (riid == __uuidof(IUnknown))
            *ppInterface=static_cast<IUIAutomationPropertyChangedEventHandler*>(this);
        else if (riid == __uuidof(IUIAutomationPropertyChangedEventHandler)) 
            *ppInterface=static_cast<IUIAutomationPropertyChangedEventHandler*>(this);
        else 
        {
            *ppInterface = NULL;
            return E_NOINTERFACE;
        }
        this->AddRef();
        return S_OK;
    }

    // IUIAutomationPropertyChangedEventHandler methods.
    HRESULT STDMETHODCALLTYPE HandlePropertyChangedEvent(IUIAutomationElement* pSender, PROPERTYID propertyID, VARIANT newValue) 
    {
        _eventCount++;
        if (propertyID == UIA_ToggleToggleStatePropertyId) 
            wprintf(L">> Property ToggleState changed! ");
        else 
            wprintf(L">> Property (%d) changed! ", propertyID);

        if (newValue.vt == VT_I4) 
            wprintf(L"(0x%0.8x) ", newValue.lVal);

        wprintf(L"(count: %d)\n", _eventCount);
        return S_OK;
    }
};

int main(int argc, char* argv[]) 
{
    HRESULT hr;
    int ret = 0;
    IUIAutomationElement* pTargetElement = NULL;
    EventHandler* pEHTemp = NULL;

    CoInitializeEx(NULL,COINIT_MULTITHREADED);

    IUIAutomation* pAutomation = NULL;
    hr = CoCreateInstance(__uuidof(CUIAutomation), NULL, CLSCTX_INPROC_SERVER, __uuidof(IUIAutomation), (void**)&pAutomation);
    if (FAILED(hr) || pAutomation==NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Use the mouse to point to the element you want to listen from.\n");
    Sleep(3000);

    // Make this application dots-per-inch (DPI) aware.
    SetProcessDPIAware();

    // Get mouse cursor position and get element from point.
    POINT pt;
    GetPhysicalCursorPos(&pt);
    hr = pAutomation->ElementFromPoint(pt, &pTargetElement);
    if (FAILED(hr) || pTargetElement==NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    pEHTemp = new EventHandler();
    if (pEHTemp == NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    PROPERTYID pPIDProperties[] = { UIA_ToggleToggleStatePropertyId };

    wprintf(L"-Adding Event Handler.\n");
    hr = pAutomation->AddPropertyChangedEventHandlerNativeArray(pTargetElement, TreeScope_Subtree, NULL, (IUIAutomationPropertyChangedEventHandler*) pEHTemp, pPIDProperties, sizeof(pPIDProperties) / sizeof(pPIDProperties[0]));
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Press any key to remove event handler and exit\n");
    getchar();

    wprintf(L"-Removing Event Handler.\n");
    hr = pAutomation->RemovePropertyChangedEventHandler(pTargetElement, (IUIAutomationPropertyChangedEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }

    // Release resources and terminate.
cleanup:
    if (pEHTemp != NULL) 
        pEHTemp->Release();

    if (pTargetElement != NULL) 
        pTargetElement->Release();

    if (pAutomation != NULL) 
        pAutomation->Release();

    CoUninitialize();
    return ret;
}

Structure-Changed イベントの処理

次のコード例は、構造変更イベントのハンドラーを実装する Windows コンソールアプリケーションです。

// Defines an event handler for structure-changed events, and 
// listens for them on the element specifies by the user.
#include <windows.h>
#include <stdio.h>
#include <UIAutomation.h>

class EventHandler:
    public IUIAutomationStructureChangedEventHandler
{
private:
    LONG _refCount;

public:
    int _eventCount;

    // Constructor.
    EventHandler(): _refCount(1), _eventCount(0) 
    {
    }

    // IUnknown methods.
    ULONG STDMETHODCALLTYPE AddRef() 
    {
        ULONG ret = InterlockedIncrement(&_refCount);
        return ret;
    }

    ULONG STDMETHODCALLTYPE Release() 
    {
        ULONG ret = InterlockedDecrement(&_refCount);
        if (ret == 0) 
        {
            delete this;
            return 0;
        }
        return ret;
    }

    HRESULT STDMETHODCALLTYPE QueryInterface(REFIID riid, void** ppInterface) 
    {
        if (riid == __uuidof(IUnknown))
            *ppInterface=static_cast<IUIAutomationStructureChangedEventHandler*>(this);
        else if (riid == __uuidof(IUIAutomationStructureChangedEventHandler)) 
            *ppInterface=static_cast<IUIAutomationStructureChangedEventHandler*>(this);
        else 
        {
            *ppInterface = NULL;
            return E_NOINTERFACE;
        }
        this->AddRef();
        return S_OK;
    }

    // IUIAutomationStructureChangedEventHandler methods
    HRESULT STDMETHODCALLTYPE HandleStructureChangedEvent(IUIAutomationElement* pSender, StructureChangeType changeType, SAFEARRAY* pRuntimeID) {
        _eventCount++;
        switch (changeType) 
        {
            case StructureChangeType_ChildAdded:
                wprintf(L">> Structure Changed: ChildAdded! (count: %d)\n", _eventCount);
                break;
            case StructureChangeType_ChildRemoved:
                wprintf(L">> Structure Changed: ChildRemoved! (count: %d)\n", _eventCount);
                break;
            case StructureChangeType_ChildrenInvalidated:
                wprintf(L">> Structure Changed: ChildrenInvalidated! (count: %d)\n", _eventCount);
                break;
            case StructureChangeType_ChildrenBulkAdded:
                wprintf(L">> Structure Changed: ChildrenBulkAdded! (count: %d)\n", _eventCount);
                break;
            case StructureChangeType_ChildrenBulkRemoved:
                wprintf(L">> Structure Changed: ChildrenBulkRemoved! (count: %d)\n", _eventCount);
                break;
            case StructureChangeType_ChildrenReordered:
                wprintf(L">> Structure Changed: ChildrenReordered! (count: %d)\n", _eventCount);
                break;
        }
        return S_OK;
    }
};

int main(int argc, char* argv[]) 
{
    HRESULT hr;
    int ret = 0;
    IUIAutomationElement* pTargetElement = NULL;
    EventHandler* pEHTemp = NULL;

    CoInitializeEx(NULL,COINIT_MULTITHREADED);

    IUIAutomation* pAutomation=NULL;
    hr = CoCreateInstance(__uuidof(CUIAutomation), NULL, CLSCTX_INPROC_SERVER, __uuidof(IUIAutomation), (void**)&pAutomation);
    if (FAILED(hr) || pAutomation == NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Use the mouse to point to the element you want to listen from.\n");
    Sleep(3000);

    // Make this application dots-per-inch (DPI) aware.
    SetProcessDPIAware();

    // Get mouse cursor position and get element from point.
    POINT pt;
    GetPhysicalCursorPos(&pt);
    hr = pAutomation->ElementFromPoint(pt, &pTargetElement);
    if (FAILED(hr) || pTargetElement == NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    pEHTemp = new EventHandler();
    if (pEHTemp == NULL) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Adding Event Handler.\n");
    hr = pAutomation->AddStructureChangedEventHandler(pTargetElement, TreeScope_Subtree, NULL, (IUIAutomationStructureChangedEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }

    wprintf(L"-Press any key to remove event handler and exit\n");
    getchar();

    wprintf(L"-Removing Event Handler.\n");
    hr = pAutomation->RemoveStructureChangedEventHandler(pTargetElement, (IUIAutomationStructureChangedEventHandler*) pEHTemp);
    if (FAILED(hr)) 
    {
        ret = 1;
        goto cleanup;
    }

    // Release resources and terminate.
cleanup:
    if (pEHTemp != NULL) 
        pEHTemp->Release();

    if (pTargetElement != NULL) 
        pTargetElement->Release();

    if (pAutomation != NULL) 
        pAutomation->Release();

    CoUninitialize();
    return ret;
}

概念
UI オートメーションイベントのサブスクライブ
UI オートメーションクライアントの操作方法に関するトピック

次の方法で共有

イベントハンドラーを実装する方法

一般的なUI オートメーションイベントの処理

Focus-Changed イベントの処理

Property-Changed イベントの処理

Structure-Changed イベントの処理

フィードバック

その他のリソース

次の方法で共有

イベント ハンドラーを実装する方法

一般的なUI オートメーション イベントの処理

Focus-Changed イベントの処理

Property-Changed イベントの処理

Structure-Changed イベントの処理

関連トピック

フィードバック

その他のリソース

イベントハンドラーを実装する方法

一般的なUI オートメーションイベントの処理