I need to search for maximized windows from Win32 (by using EnumWindows) but I also want to filter for windows which are on the current virtual desktop. On MSDN, I found a page about the IVirtualDesktopManager interface but there seems to be no information on how to use this interface.
IVirtualDesktopManager::IsWindowOnCurrentVirtualDesktop(/*args...*/);
Throws the following error:
Non static member reference must be relative to a specific object
VirtualDesktopManager mVirtualDeskManager;
mVirtualDesktopManager.IsWindowOnCurrentVirtualDesktop(/args...*/)
Throws this error:
Incomplete type is not allowed
I have only found solutions on using the IVirtualDesktopManager interface in C# yet.
IVirtualDesktopManager is a COM interface. You need to instantiate the COM object that implements the interface.
Based on code from this blog, you can use IServiceProvider to access IVirtualDesktopManager (and IVirtualDesktopManagerInternal, which has much more functionality than IVirtualDesktopManager has), eg:
IServiceProvider* pServiceProvider = NULL;
HRESULT hr = ::CoCreateInstance(
CLSID_ImmersiveShell, NULL, CLSCTX_LOCAL_SERVER,
__uuidof(IServiceProvider), (PVOID*)&pServiceProvider);
if (SUCCEEDED(hr))
{
IVirtualDesktopManager *pDesktopManager = NULL;
hr = pServiceProvider->QueryService(__uuidof(IVirtualDesktopManager), &pDesktopManager);
if (SUCCEEDED(hr))
{
BOOL bIsOnCurrentDesktop = FALSE;
hr = pDesktopManager->IsWindowOnCurrentVirtualDesktop(hWnd, &bIsOnCurrentDesktop);
if (SUCCEEDED(hr))
{
// use bIsOnCurrentDesktop as needed...
}
pDesktopManager->Release();
}
pServiceProvider->Release();
}
Related
I have a COM project which does not support MFC and needs to communicate with another App through a MFC interface.
I cannot use directly in MFC interface with my COM project as it is not an MFC project.
A solution was to create an automation interface for the Of the MFC interface which I would be able to use as a layer through which my COM project can communicate to the MFC project.
As I understood, the automation app will run in a different thread. My COM project will invoke methods from the automation interface to call the MFC interface.
The Automation project and its IDL file were provided to me and provides me with a Pure Dispinterface.
Before integrating the implementation of the IDispatch interface to my COM project I decided to create a new C++ console project in order to focus on simply using the automation interface.
Using the documentation provided by microsoft (https://learn.microsoft.com/en-us/previous-versions/windows/desktop/automat/implementing-the-idispatch-interface) I implemented the IDispatch interface as follows:
#include "TTAutomate.h"
HRESULT hresult;
DISPID dispid;
DISPPARAMS dispparamsNoArgs = { NULL, NULL, 0, 0 };
EXCEPINFO excepinfo;
UINT nArgErr;
ClassFromIDL* m_ClassFromIDL;
_DTTAutomateEvents* m_DTTAutomateEvents;
_DTTAutomate* m_DTTAutomate;
hresult = OleInitialize(NULL);
// OLE function CoCreateInstance starts application using GUID.
hresult = CoCreateInstance(CLSID_TTfromIDL, NULL, CLSCTX_INPROC_SERVER, DIID__DTTAutomateEvents, (LPVOID*)m_Automate);
// Call QueryInterface to see if object supports IDispatch.
hresult = m_ClassFromIDL->QueryInterface(DIID__DTTfromIDL, (LPVOID*)pdisp);
// Retrieve the dispatch identifier for the SayHello method.
// Use defaults where possible.
OLECHAR* szMember = "SayHello";
DISPID dispid_Item;
hresult = pdisp->GetIDsOfNames(
IID_NULL,
&szFunction,
1,
LOCALE_USER_DEFAULT,
&dispid_Item);
First of all the implementation is a bit different as the one in the documentation because with the line :
hresult = CoCreateInstance(CLSID_Hello, NULL, CLSCTX_SERVER, IID_IUnknown, (void **)&punk);
I would get an error "amp undefined".
With the code above I currently get an error stating a const char * cannot initialize a OLECHAR *.
On my COM project I have a line:
LPOLESTR szFunction = OLESTR("SayHello");
which compiles but the same line on my test project does not work.
Did I miss some includes to add?
Did I not create the right kind of test project?
So I found a way to fix my code so that it compiles but not exactly sure if it is a proper solution:
#include "TTAutomate.h"
#include <string>
HRESULT hresult;
DISPID dispid;
DISPPARAMS dispparamsNoArgs = { NULL, NULL, 0, 0 };
EXCEPINFO excepinfo;
UINT nArgErr;
ClassFromIDL* m_ClassFromIDL;
IDispatch* m_Automate; // fixed
hresult = OleInitialize(NULL);
// OLE function CoCreateInstance starts application using GUID.
hresult = CoCreateInstance(CLSID_TTfromIDL, NULL, CLSCTX_INPROC_SERVER, DIID__DTTAutomateEvents, (void**)&m_Automate); // fixed
// Call QueryInterface to see if object supports IDispatch.
hresult = m_ClassFromIDL->QueryInterface(DIID__DTTfromIDL, (void**)&pdisp); // fixed
// Retrieve the dispatch identifier for the SayHello method.
// Use defaults where possible.
// here I create a wchar_t* variable as LPOESTR is casted from that.
std::string functionName = "SayHello";
int wchars_num = MultiByteToWideChar(CP_UTF8, 0, functionName.c_str(), -1, NULL, 0);
wchar_t* wstr = new wchar_t[wchars_num];
LPOLESTR szMember = wstr;
DISPID dispid_Item;
hresult = pdisp->GetIDsOfNames(
IID_NULL,
&szFunction,
1,
LOCALE_USER_DEFAULT,
&dispid_Item);
I now get a E_NOINTERFACE No such interface supported but it is probably unrelated to this topic.
I'm trying to figure out if it is possible to use OR re-create the CFolderPickerDialog dialog without using MFC, or if there has been an attempt. So far I did not find a lot of hints. This old question does not seem to help me either.
I currently open the normal folder dialog with SHBrowseForFolder. But I need an Explorer-style dialog.
Here is the Explorer-style dialog (MFC) from another application:
#include <afxdlgs.h> requires MFC. I cannot use MFC in this specific project.
Is there a way to do this without using MFC ?
Honestly, I didn't even know that MFC had wrapped this. My class library has its own implementation. And, as Barmak points out, the MFC implementation may even be buggy, and certainly has usage caveats that would not be obvious had you failed to read the documentation carefully.
That said, in general, it is good advice to use functionality that is already wrapped up in a library because this makes your life easier. If you don't want to use the whole library, but still want to see how it implements a particular feature, you can check the library's source code. MFC is provided with reference source so that you can do this easily (also so you can debug it). Although it would probably be a violation of the license to copy and paste code directly out of MFC (it would also be nigh-impossible, since it uses so many MFC-specific idioms), you can look at the code to see what they're doing, then go back to the Windows SDK documentation to figure out how to write the code yourself.
In this case, the relevant SDK documentation is here. Modern versions of Windows (since Vista) use the Common Item Dialog API to display open/save file/folder dialogs. The API consists of a base IFileDialog interface, with two sub-interfaces, IFileOpenDialog and IFileSaveDialog. There is a lot of flexibility here; the details are in the documentation, along with sample code.
Note that the Common Item Dialog is only available on Windows Vista and later. If you need to support older operating systems (I still support Windows XP), you need a fallback. The SHBrowseForFolder dialog is that fallback. It certainly has its design flaws, but it is better than nothing.
If all you want is a simple folder-picker dialog, here is an approximation of the code that I use. It uses a couple of ATL/MFC types, like the CString and CComPtr wrapper classes, but you can translate that to alternate classes of your own choosing (such as std::wstring and _com_ptr_t). It displays a simple browse-for-folder dialog, appropriate for the current operating system, with a caller-specified title and starting path. If it succeeds, it returns a string containing the path to the folder selected by the user; otherwise, it returns an empty string.
namespace
{
HRESULT Downlevel_SHCreateItemFromParsingName(PCWSTR pszPath, IBindCtx* pbc, REFIID riid, void** ppv)
{
_ASSERTE(IsWinVistaOrLater());
HRESULT hResult = HRESULT_FROM_WIN32(ERROR_NOT_SUPPORTED);
const HINSTANCE hinstLib = GetModuleHandle(TEXT("shell32"));
if (hinstLib)
{
typedef HRESULT (WINAPI * pfSHCreateItemFromParsingName)(PCWSTR, IBindCtx*, REFIID, void**);
const pfSHCreateItemFromParsingName pf = reinterpret_cast<pfSHCreateItemFromParsingName>(GetProcAddress(hinstLib, _CRT_STRINGIZE(SHCreateItemFromParsingName)));
if (pf)
{
hResult = pf(pszPath, pbc, riid, ppv);
}
}
return hResult;
}
int CALLBACK BrowseForFolderCallbackProc(HWND hWnd, UINT uMsg, LPARAM /* lParam */, LPARAM lData)
{
if (uMsg == BFFM_INITIALIZED)
{
// Start with BFFM_SETSELECTION, which is always available.
SendMessage(hWnd, BFFM_SETSELECTION, TRUE, lData);
#ifdef UNICODE
// If possible, also try to use BFFM_SETEXPANDED, which was introduced with
// version 6.0 of the shell (Windows XP).
SendMessage(hWnd, BFFM_SETEXPANDED, TRUE, lData);
// You can also set the caption for the dialog's "OK" button here, if you like
// (e.g., by loading a string from a resource).
//SendMessage(hWnd,
// BFFM_SETOKTEXT,
// 0,
// reinterpret_cast<LPARAM>(pszOKBtnCaption));
#endif // UNICODE
}
return 0;
}
}
CString ShowFolderBrowserDialog(HWND hwndOwner, const CString& strDlgTitle, const CString& strStartPath)
{
if (IsWinVistaOrLater())
{
CComPtr<IFileOpenDialog> pFileOpenDlg;
if (SUCCEEDED(pFileOpenDlg.CoCreateInstance(__uuidof(FileOpenDialog))))
{
if (SUCCEEDED(pFileOpenDlg->SetTitle(strDlgTitle)))
{
FILEOPENDIALOGOPTIONS options;
if (SUCCEEDED(pFileOpenDlg->GetOptions(&options)))
{
if (SUCCEEDED(pFileOpenDlg->SetOptions(options | FOS_PATHMUSTEXIST | FOS_PICKFOLDERS | FOS_FORCEFILESYSTEM)))
{
CComPtr<IShellItem> psiStartPath;
if (SUCCEEDED(Downlevel_SHCreateItemFromParsingName(static_cast<const TCHAR*>(strStartPath),
NULL,
IID_PPV_ARGS(&psiStartPath))))
{
if (SUCCEEDED(pFileOpenDlg->SetFolder(psiStartPath)))
{
if (SUCCEEDED(pFileOpenDlg->Show(hwndOwner)))
{
CComPtr<IShellItem> pShellItemResult;
pFileOpenDlg->GetResult(&pShellItemResult);
CComHeapPtr<TCHAR> pszSelectedItem;
if (SUCCEEDED(pShellItemResult->GetDisplayName(SIGDN_FILESYSPATH, &pszSelectedItem)))
{
return pszSelectedItem;
}
}
}
}
}
}
}
}
}
else
{
TCHAR szBuffer[MAX_PATH + 1];
szBuffer[0] = TEXT('\0');
BROWSEINFO bi;
bi.hwndOwner = hwndOwner;
bi.pidlRoot = nullptr;
bi.pszDisplayName = szBuffer;
bi.lpszTitle = strDlgTitle;
bi.ulFlags = BIF_RETURNONLYFSDIRS | BIF_NEWDIALOGSTYLE | BIF_SHAREABLE | BIF_NONEWFOLDERBUTTON;
bi.lpfn = BrowseForFolderCallbackProc;
bi.lParam = reinterpret_cast<LPARAM>(static_cast<const TCHAR*>(strStartPath));
CComHeapPtr<ITEMIDLIST> pidl(SHBrowseForFolder(&bi));
if (pidl && SHGetPathFromIDList(pidl, szBuffer))
{
return pszSelectedItem;
}
}
return TEXT("");
}
The dialog only shows actual folders in the filesystem. Although the Common Item Dialog API supports other types of special folders and namespaces, I don't need that in my app, so my code doesn't deal with the complexity. Use this as a starting point, along with the documentation, if you need more features. The most notable aspect is probably the use of SHCreateItemFromParsingName (which I have wrapped up in a dynamic call so that the code continues to run on older operating systems) to translate the caller-specified starting path (which is a string) to a Shell item object (as required by the Common Item Dialog API).
Use case: Someone asked me to automate his internet explorer. Every day, he has to navigate to the same URL, enter the same credentials und log in. He'd like the computer to do that automatically: With an application that navigates to the URL, enters the post data and logs in automatically. He then can continue to navigate manually through the page.
So, if I want to control directly an existing internet explorer instance, how would I do that with C++?
After hours of research, I managed to open a new instance of the IE and navigating to a specific URL.
The steps I undertook:
Link the following libraries in the project options: libole32.a, liboleaut32.a, liboleacc.a, libuuid.a
Include cassert and exdisp.h at the beginning of the main cpp-file.
Insert the following code in the main cpp-file:
int main(void) {
HRESULT hret;
hret=CoInitialize(NULL);
assert(SUCCEEDED(hret));
CLSID clsid; // Get IE CLSID
hret=CLSIDFromProgID(L"InternetExplorer.Application",&clsid);
assert(SUCCEEDED(hret));
IUnknown *p; // Get IUnknown Interface
hret=CoCreateInstance(clsid,NULL,CLSCTX_ALL,IID_IUnknown,reinterpret_cast<void**>(&p));
assert(SUCCEEDED(hret));
IDispatch *q; // Get IDispatch Interface from IUnknown
hret=p->QueryInterface(IID_IDispatch,reinterpret_cast<void**>(&q));
assert(SUCCEEDED(hret));
IWebBrowser2 *r; // Get IWebBrowser2 Interface from IDispatch
hret=q->QueryInterface(IID_IWebBrowser2,reinterpret_cast<void**>(&r));
assert(SUCCEEDED(hret));
IUnknown *s; // Get IUnknown from IWebBrowser2
hret=r->QueryInterface(IID_IUnknown,reinterpret_cast<void**>(&s));
assert(SUCCEEDED(hret));
///// Transitive //////////////////////////
assert(p==s);
////////////////////////////////////////
VARIANT vEmpty;
VariantInit(&vEmpty);
VARIANT vFlags;
V_VT(&vFlags) = VT_I4;
V_I4(&vFlags) = navOpenInNewWindow;
BSTR bstrURL = SysAllocString(L"http://www.google.com");
r->Navigate(bstrURL, &vFlags, &vEmpty, &vEmpty, &vEmpty);
r->Quit();
SysFreeString(bstrURL);
p->Release(); q->Release(); r->Release(); s->Release();
CoUninitialize(); return 0;
}
I hope this falls within the realm of this forum:
I want to use the windows shell(?) to allow users to select a number of files before allowing my programme to do a few things to them. For this I found the MSDN sample "CommonFileDialogModes" - http://msdn.microsoft.com/en-us/library/windows/desktop/dd940350%28v=vs.85%29.aspx
In the sample under this class:
class CFileOpenBasketPickerCallback : public IFileDialogEvents, public IFileDialogControlEvents
they have this function:
// IFileDialogEvents
IFACEMETHODIMP OnFileOk(IFileDialog *pfd)
{
// if this button is in the "Add" mode then do this, otherwise return S_OK
IFileOpenDialog *pfod;
HRESULT hr = pfd->QueryInterface(IID_PPV_ARGS(&pfod));
if (SUCCEEDED(hr))
{
IShellItemArray *psia;
hr = pfod->GetSelectedItems(&psia);
if (SUCCEEDED(hr))
{
ReportSelectedItems(pfd, psia);
psia->Release();
}
pfod->Release();
}
return S_FALSE; // S_FALSE keeps the dialog up; return S_OK to allow it to dismiss.
}
which calls:
void ReportSelectedItems(IUnknown *punkSite, IShellItemArray *psia)
{
DWORD cItems;
HRESULT hr = psia->GetCount(&cItems);
for (DWORD i = 0; SUCCEEDED(hr) && (i < cItems); i++)
{
IShellItem *psi;
hr = psia->GetItemAt(i, &psi);
if (SUCCEEDED(hr))
{
PWSTR pszName;
hr = GetIDListName(psi, &pszName);
// .. I've cut some of this out for the example
CoTaskMemFree(pszName);
}
psi->Release();
}
}
}
Now I know pszName contains the names of the files selected. So I can add some extra code in to write this to disk. That works fine. But I dont want to write it to disk. I want to pass it back to the original functions that called this. The arguments for ReportSelectedItems can be altered, but IFACEMETHODIMP OnFileOk(IFileDialog *pfd) cannot as it is inherited. Adding a vector& file_names to the argument will stop it compiling.
So how should I deal with this? I could use a global variable for file_names, but everything I am learning about programming is telling me not to. It would be a quick fix, but I worry that would encourage me to be lazy in the future. I find it difficult to read the windows code and I don't really want to delve too much into the details of it. I can't even find what is calling the OnFileOk function, even though I know it is from one of the two base classes.
Do I really need to work at understanding all the library code just to get this one function doing what I'd like? Is there an faster way of going about this?
So to summarize, how would I get information from this inherited function without using a global variable or writing to disk? As I mentined before, I don't have much of a grasp of the code I am working with. And for future reference, how should I deal with this type of situation? I use c++ and would like to avoid c# and c as much as possible.
Thanks as always.
It seems a fairly big omission for Microsoft to have left out any sort of user data associated with the IFileDialog callbacks, but that does seem to be the case.
I'm assuming that simply calling GetSelectedItems() once the dialog returns is something you don't want to do for some reason - because that would obviously be the simplest solution.
From a quick look at the docs one way you may be able to pass data back from the event callback is using the owner window that you pass to IFileDialog::Show() (which is actually IModalWindow::Show()).
In the event handler, you get given the IFileDialog* pointer. From this, you can QI the address of the IOleWindow interface which will give you the dialog's window:
IFACEMETHODIMP OnFileOk(IFileDialog *pfd)
{
CComPtr<IOleWindow> pWindow;
if (SUCCEEDED(pfd->QueryInterface(IID_IOleWindow, reinterpret_cast<void**>(&pWindow))))
{
HWND hwndDlg;
if (SUCCEEDED(pWindow->GetWindow(&hwndDlg)))
{
HWND hwndOwner;
if (hwndOwner = GetWindow(hwndDlg, GW_OWNER))
{
// hwndOwner is the owner window of the dialog
}
}
}
// more code
}
Now assuming that hwndOwner is your own window, you can associate any data you like with it using SetProp()/GetProp() - so you could use this as a mechanism to pass data back from within the callback.
A simple solution was to add member data inside the inherited class and link it from the constructor:
class CFileOpenBasketPickerCallback : public IFileDialogEvents, public IFileDialogControlEvents
{
public:
CFileOpenBasketPickerCallback(vector<wstring>& files) : files_(files)
{
}
// functions
private:
vector<wstring>& files_;
};
When constructing the object
vector<std::wstring> files
CFileOpenBasketPickerCallback foacb(files);
And in IFACEMETHODIMP OnFileOk(IFileDialog *pfd)
ReportSelectedItems(pfd, psia, files_);
ReportSelectedItems is not a member so you can alter the arguments.
I can't seem to understand how i give my implementation of the IHttpSecurity::OnSecurityProblem to my IWebBrowser2 object.
I know that i need to implement a class something like this:
class CServiceProvider : public IServiceProvider
{
public:
CServiceProvider();
~CServiceProvider();
// IUnknown
ULONG STDMETHODCALLTYPE AddRef();
ULONG STDMETHODCALLTYPE Release();
STDMETHODIMP QueryInterface(REFIID iid, void ** ppvObject);
//QueryService
STDMETHODIMP QueryService(REFGUID guidService,REFIID riid,void **ppv);
private:
ULONG m_ulRefCnt;
};
And in the QueryService function when it requests the IID_IHttpSecurity i return my implementation of the IHttpSecurity interface.
But my problem is how i set the my service provider implementation on the IWebBrowser2 object and when?
My code is something like this:
IWebBrowser2 *_Browser;
IServiceProvider* pServiceProvider = NULL;
_Browser->QueryInterface(
IID_IServiceProvider,
(void**)&pServiceProvider);
IHttpSecurity* pi;
pServiceProvider->QueryService(IID_IHttpSecurity, &pi);
_Browser->Navigate(url.AllocSysString(),
&flags,
&target_frame_name,
&post_data,
&headers);
The question this works like i'm thinking if yes how i do this then, and if not can you explain how this works and can be setted?
PS: i only whant to implement the IID_IHttpSecurity interface, all other interfaces requested on the QueryService should do the default implementation provided by the system...
Thanks
I already figure out how this is done.
Using MFC we only need to implement CCustomOccManager that implements the COccManager in witch the implementation of CreateSite function returns an implementation of our COleControlSite (example CCustomControlSite). In this class you will need to override at least the QueryService function of IServiceProvider interface and in this implementation supply yours IHttpSecurity implementation (when required by the interface).
In the end the we register all this in the App InitInstance using the MFC function AfxEnableControlContainer.
Code:
// declare our custom control site to serve as the client site
class CCustomControlSite:public COleControlSite
{
public:
// constructor associates this site with the container
CCustomControlSite(COleControlContainer *pCnt):COleControlSite(pCnt){}
protected:
DECLARE_INTERFACE_MAP();
BEGIN_INTERFACE_PART(ServiceProvider, IServiceProvider)
// declare the interface method(s)
STDMETHOD(QueryService) (
/* [in] */ REFGUID guidService,
/* [in] */ REFIID riid,
/* [out] */ void __RPC_FAR *__RPC_FAR *ppvObject);
END_INTERFACE_PART(ServiceProvider)
};
// declare our control container manager
class CCustomOccManager :public COccManager
{
public:
CCustomOccManager(){}
// creates an instance of our custom control site and associates it with the container
COleControlSite* CreateSite(COleControlContainer* pCtrlCont)
{
CCustomControlSite *pSite = new CCustomControlSite(pCtrlCont);
return pSite;
}
};
In the App InitInstance simple call AfxEnableControlContainer on our implementation:
// Create a custom control container manager class so we can overide the client site
CCustomOccManager *pMgr = new CCustomOccManager;
// Set our control containment up but using our control container
// management class instead of MFC's default
AfxEnableControlContainer(pMgr);
If someone has the knowledge on how this is done without using MFC please let me know.
Thanks
Judging by the remarks in the documentation for IServiceProvider, it seems like your IOleClientSite object needs to implement IServiceProvider.