How to get LegacyIAccessible data using UiAutomation? - c++

Question

I'm trying to get the LegacyIAccessible values marked on the picture below:
So far I have been able to read these:
#include <UIAutomation.h> // UIAutomation includes.
#include <UIAutomationCore.h>
#include <UIAutomationClient.h>
#include "Oleacc.h"
#include "atlbase.h"
#pragma comment(lib,"Oleacc.lib")
LPCWSTR Acc(HWND hwnd) {
CComPtr<IUIAutomation> pUIAutomation;
CoInitialize(NULL);
HRESULT hr = CoCreateInstance(__uuidof(CUIAutomation), NULL, CLSCTX_INPROC_SERVER, __uuidof(IUIAutomation), (void**)&pUIAutomation);
if (SUCCEEDED(hr))
{
IUIAutomationElement* pRoot = NULL;
hr = pUIAutomation->ElementFromHandle(hwnd, &pRoot);
if (SUCCEEDED(hr))
{
IUIAutomationElementArray* pElementArray = nullptr;
IUIAutomationCondition* pCondition;
hr = pUIAutomation->CreateTrueCondition(&pCondition);
IUIAutomationElementArray* pEA;
IUIAutomationCacheRequest* pCacheRequest;
hr = pUIAutomation->CreateCacheRequest(&pCacheRequest);
pCacheRequest->AddProperty(UIA_NamePropertyId);
pCacheRequest->AddProperty(UIA_AutomationIdPropertyId);
pCacheRequest->AddProperty(UIA_LocalizedControlTypePropertyId);
//pCacheRequest->put_TreeScope((TreeScope)(TreeScope_Element | TreeScope_Descendants));
hr = pRoot->FindAllBuildCache(TreeScope_Descendants, pCondition, pCacheRequest, &pEA);
if (SUCCEEDED(hr))
{
int nNbItems = 0;
hr = pEA->get_Length(&nNbItems);
for (int nItem = 0; nItem <= nNbItems - 1; nItem++)
{
IUIAutomationElement* pElement = nullptr;
hr = pEA->GetElement(nItem, &pElement);
BSTR name;
pElement->get_CurrentName(&name);
UIA_HWND uia_hwnd = nullptr;
pElement->get_CurrentNativeWindowHandle(&uia_hwnd);
BSTR classname = nullptr;
pElement->get_CurrentClassName(&classname);
RECT rect;
pElement->get_CurrentBoundingRectangle(&rect);
pElement->Release();
}
}
pCacheRequest->Release();
pCondition->Release();
pRoot->Release();
}
//pUIAutomation->Release(); // <- needed?
}
CoUninitialize();
return (L"SUCCEEDED");
}
When I try to call for:
DWORD CurrentState;
pElement->get_CurrentState(&CurrentState);
I get this error: class "IUIAutomationElement" has no member "get_CurrentState".
I think I should be using IUIAutomationLegacyIAccessiblePattern but I couldn't figure out how to properly rewrite the function using it.
Also, what's the difference between the functions with and without 'cache'?

Answer 1

A example of GetCurrentPatternAs. Caching is not involved.
#include <Windows.h>
#include <UIAutomation.h>
#include <wchar.h>
int Element(IUIAutomation* automation)
{
// Get the element under the cursor
// Use GetPhysicalCursorPos to interact properly with
// High DPI
POINT pt;
GetPhysicalCursorPos(&pt);
IUIAutomationElement* pAtMouse;
HRESULT hr = automation->ElementFromPoint(pt, &pAtMouse);
if (FAILED(hr))
return hr;
// Get the element's name and print it
BSTR name;
hr = pAtMouse->get_CurrentName(&name);
if (SUCCEEDED(hr))
{
wprintf(L"Element's Name: %s \n", name);
SysFreeString(name);
//IUIAutomationValuePattern* pattern;
//pAtMouse->GetCurrentPatternAs(UIA_ValuePatternId, IID_IUIAutomationValuePattern,(void**)&pattern);
IUIAutomationLegacyIAccessiblePattern* pattern;
//pAtMouse->GetCurrentPatternAs(UIA_LegacyIAccessiblePatternId, IID_IUIAutomationLegacyIAccessiblePattern,(void**)&pattern);
pAtMouse->GetCurrentPatternAs(UIA_LegacyIAccessiblePatternId, IID_PPV_ARGS(&pattern));
//TODO
BSTR url = nullptr;
pattern->get_CurrentValue(&url);
DWORD state = 0;
pattern->get_CurrentState(&state);
BSTR elename = nullptr;
pattern->get_CurrentName(&elename);
DWORD role = 0;
pattern->get_CurrentRole(&role);
//wprintf(L"Element's ValuePattern: %s \n", url);
SysFreeString(url);
SysFreeString(elename);
}
// Get the element's Control Type (in the current languange)
// and print it
BSTR controlType;
hr = pAtMouse->get_CurrentLocalizedControlType(&controlType);
if (SUCCEEDED(hr))
{
wprintf(L"Element's Control Type: %s \n", controlType);
SysFreeString(controlType);
}
// Clean up our COM pointers
pAtMouse->Release();
return hr;
}
int main(int argc, TCHAR* argv[])
{
// Initialize COM and create the main Automation object
IUIAutomation* g_pAutomation;
CoInitialize(NULL);
HRESULT hr = CoCreateInstance(__uuidof(CUIAutomation), NULL,
CLSCTX_INPROC_SERVER, __uuidof(IUIAutomation),
(void**)&g_pAutomation);
if (FAILED(hr))
return (hr);
bool quit = false;
while (!quit)
{
SHORT leftControlMod = GetAsyncKeyState(VK_LCONTROL);
if (leftControlMod != 0)
{
Element(g_pAutomation);
}
quit = GetAsyncKeyState(VK_ESCAPE);
}
g_pAutomation->Release();
CoUninitialize();
return 0;
}