I'm trying to access text of Google Chrome's webpage to read it and offer some actions (for example, remind). Everything works good, but I need to enable accessibility inspection programmatically. I use this code:
wchar_t className[100];
GetClassName(hwnd, className, 100) == 0 || wcscmp(className, L"Chrome_WidgetWin_1");
CComPtr<IAccessible> pAccMain;
HRESULT hr = ::AccessibleObjectFromWindow(hWndChrome, 1, IID_IAccessible, (void**)(&pAccMain));
CComPtr<IAccessible> pAccMain2;
::AccessibleObjectFromWindow(hWndChrome, OBJID_CLIENT, IID_IAccessible, (void**)(&pAccMain2));
And nothing happens until I run browser with --force-renderer-accessibility parameter or manually change accessibility settings located in chrome://accessibility.
What am i doing wrong?
Found this info: "Chrome calls NotifyWinEvent with EVENT_SYSTEM_ALERT and the custom object id of 1. If it subsequently receives a WM_GETOBJECT call for that custom object id, it assumes that assistive technology is running". Does anybody know how to implement this?
Use SetWinEventHook, e.g.
HWINEVENTHOOK hook = SetWinEventHook(EVENT_SYSTEM_ALERT, EVENT_SYSTEM_ALERT,NULL, WinEventProc, 0, 0, WINEVENT_OUTOFCONTEXT)
Then in your WinEventProc, you'll be given a hWnd, idObject, and idChild when Chrome sends the EVENT_SYSTEM_ALERT.
If idObject == 1 then call AccessibleObjectFromEvent(), passing it those hWnd, idObject, and idChild arguments.
AccessibleObjectFromEvent will then send the WM_GETOBJECT. From the docs::
Applications never send this message directly. Microsoft Active Accessibility sends this message in response to calls to AccessibleObjectFromPoint, AccessibleObjectFromEvent, or AccessibleObjectFromWindow.
By using AccEvent I can see that Google Chrome only appears to send the EVENT_SYSTEM_ALERT when it starts, e.g. opening a new tab doesn't trigger it, so you'd need to have done the SetWinEventHook() before Chrome is launched.
Related
I've written a custom CredentialProvider listening to events sent via bluetooth.
So far everything works fine. Except the fact that after sending the event the login screen changes and shows a single button "Sign in" below the username.
As stated in the answers to this SO-question I did he following to achieve autologon:
HRESULT CMobileCredential2::SetSelected(_Out_ BOOL *pbAutoLogon)
{
LOG_FUNCTION;
*pbAutoLogon = true;
return S_OK;
}
and in the eventhandling code I call:
HRESULT hr = _pcpe->CredentialsChanged(_upAdviseContext);
if (S_OK != hr)
{
LOG_ERROR("Could not login!");
}
I thought that the LogonUI would automatically log me in when I set autologon to true? Why do I have to click on another button? Is there any way to avoid this behaviour?
EDIT:
The following is to be found in the "Credential Provider Technical Reference" from Microsoft:
In Windows 10, if a credential provider wants to autologon the user
where we think may be inappropriate, we will paint a “sign in” button
as a speed bump.
I think that's the point I'm hitting here, but what is inappropriate? The password used consists of lower and uppercase characters as well as some numbers. Is there any possibility to cirumvent this?
After searching for a few days I stumbled upon this answer in the microsoft-forums, that contained the solution.
As it seems, Windows does not trust the custom credential enough to bypass this "speed bump", when pbAutoLogon is set to true in SetSelected(_Out_ BOOL *pbAutoLogon).
However it trusts the custom provider, so setting pbAutoLogonWithDefault to true in
GetCredentialCount(
_Out_ DWORD *pdwCount,
_Out_ DWORD *pdwDefault,
_Out_ BOOL *pbAutoLogonWithDefault)
seems to do the trick, as GetCredentialCount is always called before calling
GetSerialization(_Out_ CREDENTIAL_PROVIDER_GET_SERIALIZATION_RESPONSE *pcpgsr,
_Out_ CREDENTIAL_PROVIDER_CREDENTIAL_SERIALIZATION *pcpcs,
_Outptr_result_maybenull_ PWSTR *ppwszOptionalStatusText,
_Out_ CREDENTIAL_PROVIDER_STATUS_ICON *pcpsiOptionalStatusIcon)
of the custom credential.
I'm a little bit confused about how to notify my c++ application with event that the user has plugged in a device (USB, HID etc.). Application type is not defined. I'm trying to play around with console/message-only/service example apps, but there is no result. I'm using VS2015 and Windows 10.
I've found out that there are multiple ways to deal with it:
Using WMI like here. But I can not actually understand where is WMI here.
Using RegisterDeviceNotification and WM_DEVICECHANGE. As far as I can understand, there is no way to do that for the console applications, only for once with the GUI (real window) or for the message-only window. I've tried the last one with the example from this answer but my app doesn't receive any notifications when I plug in my USB flash drive. I've found this answer (from the same question as the answer mentioned above) and tried to use ChangeWindowMessageFilterEx() function with GetProcAddress from user32.dll to load it without connection dll to my app in such way:
BOOL InitInstance(HWND hWnd)
{
HMODULE hDll = GetModuleHandle(TEXT("user32.dll"));
if (hDll)
{
typedef BOOL(WINAPI *MESSAGEFILTERFUNCEX)(HWND hWnd, UINT message, DWORD action, VOID* pChangeFilterStruct);
const DWORD MSGFLT_ALLOW = 1;
MESSAGEFILTERFUNCEX ChangeWindowMessageFilterEx= (MESSAGEFILTERFUNCEX)::GetProcAddress(hDll, "ChangeWindowMessageFilterEx");
if (ChangeWindowMessageFilterEx) return func(hWnd, WM_COPYDATA, MSGFLT_ALLOW, NULL);
}
return FALSE; }
And the usage of this function is:
hWnd = CreateWindowEx(0, CLS_NAME, "DevNotifWnd", WS_ICONIC,
0, 0, CW_USEDEFAULT, 0, HWND_MESSAGE,
NULL, GetModuleHandle(0), (void*)&guid);
InitInstance(hWnd);
But there is no effect.
Using while(true){...} loop and call appropriate Win API functions like in this answer. But this way seems not be a perfect solution for my problem.
My questions are:
Could anybody explain me what is the best way? And if it is the second one with RegisterDeviceNotification, why it's not working in case of message-only window app?
Do other ways exist? And if not, what can I do, for example, to notify application when some certain software was installed?
Any comments are appreciated.
So I've finally found sort of answers to the questions.
The issue was with the GUID I've provided for the NotificationFilter. So I've set it to receive notifications from all devices with this code:
DEV_BROADCAST_DEVICEINTERFACE NotificationFilter;
ZeroMemory(&NotificationFilter, sizeof(NotificationFilter));
NotificationFilter.dbcc_size = sizeof(DEV_BROADCAST_DEVICEINTERFACE);
NotificationFilter.dbcc_devicetype = DBT_DEVTYP_DEVICEINTERFACE;
// No need to set up dbcc_classguid as it is ignored when
// DEVICE_NOTIFY_ALL_INTERFACE_CLASSES is setted (see line down below)
HDEVNOTIFY dev_notify = RegisterDeviceNotification(hwnd, &NotificationFilter, DEVICE_NOTIFY_ALL_INTERFACE_CLASSES);
As far as for other types of notifications in windows that the app could sign up for, I found only one partially deprecated list of all Win32 API functions, where I found some new Notifications with Ctrl+F search :)
Hope this could save somebody's time.
It's kind of weird issue, let me try to explain. I wrote a (dialog based) app in c++/MFC that supports drag-n-dropping.
I do the following test on Windows 7 with default themes. My app is running on the screen. It is not a top window (in its z-order) or in other words it's obscured by other windows on top of it.
If I begin dragging a link or just a text selection from the Chrome or Firefox web browser, first into my app's icon on the taskbar, the icon flashes and my app pops up on the screen (by receiving the top z-order) so I can then drag-and-drop into my app. Everything works fine.
If I do the same from IE 9 (version 9.0.8112, update versions 9.0.12) when I drag selected text or a link first to the taskbar icon of my app to make my app become top window (in z-order), the app icon continues flashing but it never gets shown on the screen like it happens with Chrome or FF, so as a result I have to abandon my drag-and-drop.
Any idea why is it happening like that with IE and if there's a way to fix it?
EDIT: Here's the code sample in regards to my comments below:
HRESULT __stdcall DragEnter(IDataObject* pDataObject, DWORD grfKeyState, POINTL pt, DWORD* pdwEffect)
{
//IDropTarget::DragEnter
m_fAllowDrop = QueryDataObject(pDataObject);
if(m_fAllowDrop)
{
//SUCCESS
// get the dropeffect based on keyboard state
}
else
{
//FAILURE
*pdwEffect = DROPEFFECT_NONE;
}
return S_OK;
}
BOOL QueryDataObject(IDataObject* pDataObject, int* pnOutDataType)
{
static FORMATETC fmtetc_file = {CF_HDROP, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
static FORMATETC fmtetc_txt = {CF_UNICODETEXT, 0, DVASPECT_CONTENT, -1, TYMED_HGLOBAL};
BOOL bRes = FALSE;
HRESULT hr;
//See if our data type
hr = pDataObject->QueryGetData(&fmtetc_file);
if(hr == S_OK)
{
bRes = TRUE;
}
//In my case hr is E_FAIL or 0x80004005
hr = pDataObject->QueryGetData(&fmtetc_txt);
if(hr == S_OK)
{
bRes = TRUE;
}
//In my case hr is E_FAIL or 0x80004005
return bRes;
}
As part of its sandboxing to prevent unauthorized changes to the machine, Internet Explorer runs in a lower UIPI (User Interface Privilege Isolation) integrity level than other apps do. As such, it does not have permission to access your app by default, which is more likely to be running in a medium or high UIPI integrity level (depending on whether it is UAC elevated or not). The flashing taskbar button means that something is trying to bring your app to the foreground but does not have permission to do so (see the documentation of SetForegroundWindow() for more details). UIPI does not allow a lower-integrity process to send window messages to a higher-integrity process unless the receiving process explicitally tells UIPI to allow it. Chrome and FireFox are likely running in the same integrity level as your app. In order to support drag-and-drop from Internet Explorer, call ChangeWindowMessageFilter() or ChangeWindowMessageFilterEx() to let your app receive WM_DROPFILES, WM_COPYDATA, and WM_COPYGLOBALDATA (0x0049) messages from lower-integrity processes.
Update: It looks like Internet Explorer in particular imposes additional restrictions on drag&drop operations when it is running in Protected Mode:
How to handle drag & drop from low integrity Internet Explorer
Understanding and Working in Protected Mode Internet Explorer - Allowing Drag and Drop Operations in your Application
Good afternoon, i have a section of code i am using to monitor screen saver activity in Windows XP onwards, this currently works correctly on all Windows OS's except for Windows 7, i am aware that certain screen saver parameters to the SystemParametersInfo function are not available in Windows 7 but thought that SPI_GETSCREENSAVERRUNNING was available, the code is as follows:
BOOL bScrnSvrRunning = FALSE;
BOOL bResult = SystemParametersInfo(SPI_GETSCREENSAVERRUNNING, 0, &boolScreenSaverRunning, 0);
The function always returns true for bResult but bScrnSvrRunning is always false,
does anyone have any idea what might cause this?
If you really want to monitor the screen saver activity you can consider to use System Event Notification Service (SENS). The System Event Notification Service monitors and dispatches there, so it can notify your application about the starting (see ISensLogon::StartScreenSaver) and stopping (see ISensLogon::StopScreenSaver) of the screen saver many events. An example how to use SENS you can find here (see also here and here).
You are using the wrong parameter "slot". Look closely at the declaration of SystemParametersInfo:
BOOL WINAPI SystemParametersInfo(
__in UINT uiAction,
__in UINT uiParam,
__inout PVOID pvParam,
__in UINT fWinIni
);
And let me quote the info for SPI_GETSCREENSAVERRUNNING:
Determines whether a screen saver is currently running on the window station of the calling process. The pvParam parameter must point to a BOOL variable that receives TRUE if a screen saver is currently running, or FALSE otherwise.
pvParam is the one that recieves the info, so you must supply your bool in the pvParam parameter:
BOOL bScrnSvrRunning = FALSE;
BOOL bResult = SystemParametersInfo(SPI_GETSCREENSAVERRUNNING, 0, &boolScreenSaverRunning, 0);
The MSDN documentation on WebBrowser Customization explains how to prevent new windows from being opened and how to cancel navigation. In my case, my application is hosting an IWebBrowser2 but I don't want the user to navigate to new pages within my app. Instead, I'd like to open all links in a new IE window. The desired behavior is: user clicks a link, and a new window opens with that URL.
A similar question was asked and answered here and rather than pollute that answered post, it was suggested I open a new discussion.
The members on the related post suggested I should be able to do this by trapping DISPID_BEFORENAVIGATE2, setting the cancel flag, and writing code to open a new window, but I've found out that the browser control gets lots of BeforeNavigate2 events that seem to be initiated by scripts on the main page. For example, amazon.com fires BeforeNavigate2 events like crazy, and they are not a result of link invocation.
Replies appreciated!
What I ended up doing was using IHTMLDocument directly rather than IWebBrowser. IWebBrowser is a superset of IHTMLDocument, and the navigation model implemented by IWebBrowser isn't customizable to the degree I wanted.
I actually got MS Developer Support involved and this approach was their recommendation. They say this is what Outlook uses for HTML-based email, which is the user experience I wanted to emulate. They also confirmed that there's no reliable way to filter the OnBeforeNavigate events that result from user action from those that result from script activity.
Hope this helps anybody facing the same issues. It wasn't too hard to port the code to use IHTMLDocument. If you end up doing this, you may also find yourself looking for a way to figure out when the document is done loading. To do that, hook HTMLDocumentEvents instead of DWebBrowserEvents, and look for the DISPID_HTMLDOCUMENTEVENTS_ONREADYSTATECHANGE event. It doesn't tell you what the ready state is; you need to call IHTMLDocument::get_readyState and parse the resulting string. Goofy, but there you go.
You can bind to onclick event before document is complete while creating browser in OnCreate() using IHTMLDocument2::put_onclick():
#include <comutil.h>
ClickEvents<RootFrame> clickEvents;
_variant_t clickDispatch;
clickDispatch.vt = VT_DISPATCH;
clickDispatch.pdispVal = &clickEvents;
CComQIPtr<IDispatch> dispatch;
hr = webBrowser2->get_Document(&dispatch);
ASSERT_EXIT(SUCCEEDED(hr), "webBrowser->get_Document(&dispatch)");
CComQIPtr<IHTMLDocument2> htmlDocument2;
hr = dispatch->QueryInterface(IID_IHTMLDocument2, (void**) &htmlDocument2);
ASSERT_EXIT(SUCCEEDED(hr), "dispatch->QueryInterface(&htmlDocument2)");
htmlDocument2->put_onclick(clickDispatch);
ClickEvents class implements IDispatch, you only need to implement Invoke method, in rest return E_NOTIMPL:
HRESULT STDMETHODCALLTYPE Invoke(DISPID dispIdMember, REFIID riid, LCID lcid, WORD wFlags,
DISPPARAMS *pDispParams, VARIANT *pVarResult, EXCEPINFO *pExcepInfo, UINT *puArgErr)
{
HRESULT hr;
CComQIPtr<IWebBrowser2> webBrowser2;
hr = rootFrame->GetDlgControl(rootFrame->rootview.GetDlgCtrlID(), IID_IWebBrowser2, (void**) &webBrowser2);
ASSERT_EXIT(SUCCEEDED(hr), "rootframe->GetDlgControl(IID_IWebBrowser2) failed");
CComQIPtr<IDispatch> dispatch;
hr = webBrowser2->get_Document(&dispatch);
ASSERT_EXIT(SUCCEEDED(hr), "webBrowser2->get_Document(&dispatch)");
CComQIPtr<IHTMLDocument2> htmlDocument2;
hr = dispatch->QueryInterface(IID_IHTMLDocument2, (void**) &htmlDocument2);
ASSERT_EXIT(SUCCEEDED(hr), "dispatch->QueryInterface(&htmlDocument2)");
CComQIPtr<IHTMLWindow2> htmlWindow2;
hr = htmlDocument2->get_parentWindow((IHTMLWindow2**) &htmlWindow2);
ASSERT_EXIT(SUCCEEDED(hr), "htmlDocument2->get_parentWindow(&htmlWindow2)");
CComQIPtr<IHTMLEventObj> htmlEvent;
hr = htmlWindow2->get_event(&htmlEvent);
ASSERT_EXIT(SUCCEEDED(hr), "htmlWindow2->get_event(&htmlEvent)");
CComQIPtr<IHTMLElement> htmlElement;
hr = htmlEvent->get_srcElement(&htmlElement);
ASSERT_EXIT(SUCCEEDED(hr), "htmlEvent->get_srcElement(&htmlElement)");
CComBSTR hrefAttr(L"href");
VARIANT attrValue;
VariantInit(&attrValue);
hr = htmlElement->getAttribute(hrefAttr, 0 | 2, &attrValue); // 0 = case insensitive, 2 = return BSTR
ASSERT_EXIT(SUCCEEDED(hr), "htmlElement->getAttribute()");
wchar_t href[2084]; // maximum url length in IE, http://support.microsoft.com/kb/208427
wcsncpy_s(href, _countof(href), attrValue.bstrVal, _TRUNCATE);
if (!rootFrame->IsURLAllowed(href)) {
VARIANT variant;
variant.vt = VT_BOOL;
variant.boolVal = VARIANT_FALSE;
htmlEvent->put_returnValue(variant);
ShellExecute(0, L"open", href, 0, 0, SW_SHOWNORMAL);
}
return S_OK;
}
As you can see after querying some interfaces I finally have the element that got clicked, then I call IsURLAllowed() defined in my root frame to check whether to allow opening url in current webbrowser window or whether to open it using default browser on user's computer.
This handles all links even if they were appended to document using javascript.
The same should be done with "onsubmit" events for forms.
I also think I have a solution for "window.location" redirects in javascript, I haven't tested it yet, but I will soon test it and I will update this answer then. You could use a combination of "onunload" and "onbeforeunload" events along with DWebBrowserEvents2::BeforeNavigate2(), after onunload/onbeforeunload are called you will know that user is leaving current page so now in BeforeNavigate2() you can cancel it. You can attach unload events using IHTMLWindow2::put_onunload() and IHTMLWindow2::put_onbeforeunload().
See sources of a complete solution for the "onclick" below.
AttachClickEvents in BrowserFrame:
http://code.google.com/p/phpdesktop/source/browse/phpdesktop-msie/msie/browser_frame.h?r=709d00b991b5#125
Invoke in ClickEvents(IDispatch):
http://code.google.com/p/phpdesktop/source/browse/phpdesktop-msie/msie/click_events.h?r=a5b0b350c933#132
I'm hypothesising here but yet another approach could be to maintain a count of navigation events, incrementing the counter on DISPID_BEFORENAVIGATE2 and decrementing it on occurrences of DISPID_NAVIGATECOMPLETE2 and DISPID_NAVIGATEERROR. With that in place, you could speculate that whenever you get DISPID_BEFORENAVIGATE2 and your counter is at zero, it is actual user navigation / link invocation.
I have no idea whether this approach would work, or whether those are the right events you'd need to make it work, but it could be worth investigating.
You could try a different approach instead and physically add the attribute target="_blank"
to all <a> tags in the rendered document.
This approach would involve waiting for DISPID_DOCUMENTCOMPLETE and then using IHTMLDocument3::getElementsByTagName() to fetch all of the anchor elements. You would then use IHTMLElement::setAttribute() to set target="_blank" on each of them.
It seems to me, that it you want "to open all links in a new IE window", it means that you want that the opening of new windows must be done in another process. The easiest way to do so: using CreateObject("InternetExplorer.Application") way (see another question which solve a problem, which is opposite to your question: InternetExplorer.Application object and cookie container). With this way you will receive the best isolation from your application and the user who clicks on the link receive all possibilities which exist in IE. You should of cause continue usage of BeforeNavigate2 events to find out the moment when "a new IE window" should be opened.