Getting ActiveX window handle - c++

I have followed this link to get the window handle of a ActiveX control
Sample Code from microsoft's site
// The following code should return the actual parent window of the ActiveX control.
HWND CMyOleControl::GetActualParent()
{
HWND hwndParent = 0;
// Get the window associated with the in-place site object,
// which is connected to this ActiveX control.
if (m_pInPlaceSite != NULL)
m_pInPlaceSite->GetWindow(&hwndParent);
return hwndParent; // Return the in-place site window handle.
}
But in my case I keep finding that "m_pInPlaceSite" is always NULL. I'm trying to run this code in my controls FinalConstruct. Is there something else I need to implement for the m_pInPlaceSite to be given a value? Or do I need to Query to get the value.
Thanks

FinalConstruct is way too early. In FinalConstruct your class is just being created and is not yet initialized. There is no "in place" site, there is no yet site at all.
Your control will be called by its owner, it will be given its site, then activated - only then you will possibly have m_pInPlaceSite available.

Related

How to get CDocument for derived CMFCShellTreeCtl on an Outlook Style MFC program?

I am new to MFC and have built an "outlook" style MFC app using the wizard. I've extended the CMFCShellTreetCtrl using CMyShellTreeCtrl and had data member variables and all was working fine. Now I want to move the data over to the CDocument class. Since there is several accesses to the data as each item is clicked or enumerated, I thought I would create a member variable m_pDoc to access the public variables in the CDocument. The problem I'm having, I can't find where to get the CDocument as it appears it's not setup when the trees OnCreate is called. That is in OnCreate
CWnd* pWndMain = AfxGetMainWnd();
ASSERT(pWndMain);
ASSERT(pWndMain->IsKindOf(RUNTIME_CLASS(CFrameWnd)) && !pWndMain->IsKindOf(RUNTIME_CLASS(CMDIFrameWnd))); // Not an SDI app.
m_pDoc = (CMyDoc*) ((CFrameWnd*)pWndMain)->GetActiveDocument();
returns NULL in m_pDoc and if I tried in an AfterCreate() (which is called after CreateOutlookBar) it's too late as m_pDoc is already being used and get a crash.
// Create and setup "Outlook" navigation bar:
if (!CreateOutlookBar(m_wndNavigationBar, ID_VIEW_NAVIGATION, m_wndTree, m_wndCalendar, 250))
{
TRACE0("Failed to create navigation pane\n");
return -1; // fail to create
}
m_wndTree.AfterCreate();
Any Ideas?
TIA!!
I came up with the following but I'm not sure if this is the proper way. Again, I'm new to MFC (I always have used Win32 directly). This works so it's AN answer, but is it THE correct answer?
POSITION docpos = AfxGetApp()->GetFirstDocTemplatePosition();
CDocTemplate *doctemplate = AfxGetApp()->GetNextDocTemplate(docpos);
docpos=doctemplate->GetFirstDocPosition();
m_pDoc = (CMyDoc*)doctemplate->GetNextDoc(docpos);
ASSERT(m_pDoc);
ASSERT(m_pDoc->IsKindOf(RUNTIME_CLASS(CMyDoc)));
TIA!!

MFC - Changing dialog item focus programmatically

I have a Modeless dialog which shows a bunch of buttons; some of these are customized to draw stuff with GDI.
Now, when the user clicks on a customized one under certain conditions, a message box appears to alert user of the error and this is fine.
The problem is that after accepting the Message Box (showed as MB_ICON_ERROR), everywhere I click in the dialog, I always get the error message as if the whole dialog send the message to the customized button and the only way to get rid this is to press tab and give the focus to another control.
This is a strange behaviour and knowing why happens wouldn't be bad, but a simple workaround for now should do the job.
Since the moment that is probably a matter of focus, I've tried to set it on another control (in the owner dialog) by doing:GetDlgItem( IDC_BTN_ANOTHER_BUTTON )->SetFocus();
and then, inside the customized control by adding:KillFocus( NULL );but had no results.
How should I use these functions?
Thanks in advance.
PS: if I comment the AfxMessageBox, the control does not show this bizarre behaviour.
EDITI'll show some code as requested.
// This is where Message Box is popping out. It is effectively inside the dialog code.
void CProfiloSuolaDlg::ProcessLBtnDownGraphProfilo(PNT_2D &p2dPunto)
{
// m_lboxProfiles is a customized CListBox
if(m_lboxProfiles.GetCurSel() == 0)
{
// This profile cannot be modified.
/*
CString strMessage;
strMessage.Format( _T("Default Profile cannot be edited.") );
AfxMessageBox( strMessaggio, MB_ICONERROR );
*/
return;
}
// Selecting a node from sole perimeter.
SelectNodo(p2dPoint);
}
Actually, the message is commented to keep the dialog working.
// This is inside the customization of CButton
void CMyGraphicButton::OnLButtonDown(UINT nFlags, CPoint point)
{
PNT_2D p2dPunto;
CProfiloSuolaDlg* pDlg = (CProfiloSuolaDlg*)GetParent();
m_pVD->MapToViewport(point,p2dPunto);
switch(m_uType)
{
case GRF_SEZIONE:
pDlg->ProcessLBtnDownGraphProfilo(p2dPunto);
break;
case GRF_PERIMETRO:
pDlg->ProcessLBtnDownGraphPerimetro(p2dPunto);
break;
}
CButton::OnLButtonDown(nFlags, point);
}
Since you are handling the button down event in the button handler for the custom control, you don't need to call the base class. Just comment out CButton::OnLButtonDown(nFlags, point).

MFC WebBrowser Control: How many (normal) lines of code does it take to simulate Ctrl+N?

Update: Answer: Two normal lines of code required. Thanks Noseratio!
I banged my head on the keyboard for more hours than I would have cared to trying to simulate IEs Ctrl+N behavior in my hosted Browser control app. Unfortunately, due to complications which I've abstracted out of my code examples below, I can't just let IE do Ctlr+N itself. So I have to do it manually.
Keep in mind that I am running a hosted browser. So typically, opening links in new windows will actuall open it within a new "tab" within my application (it's not really a tab, but another window... but appearance-wise it's a tab). However, Ctrl+N is different -- here, it is expected a fully-fledged IE window will launch when pressed.
I think my problem is that of framing the questions -- admittedly I am new to WebBrowser control and I find it to be a lot of yucky. Regardless, I've scoured the Internet for the past day and couldn't come up with an elegant solution.
Basically, the ideal solution would be to call a "NewWindow" function within WebBrowser control or its affiliate libraries; however, all I was able to find where the *On*NewWindow methods, which were event handlers, not event signallers. Which I understand that most of the time, the user will be creating the events... but what about programmatic simulation?
I tried looking into an SENDMESSAGE approach where I could use the IDs that the OnNewWindow events use... that ended up in nothing than crashes. Perhaps I could go back to get it work, but I'd like confirmation is that approach is even worth my time.
The next approach, which should have been the most elegeant, but sadly didn't pan out, was like the following:
Navigate2(GetLocationURL().GetBuffer(), BrowserNavConstants::navOpenInNewWindow);
It would have worked marvelously if it weren't for the fact that the new window would open in the background, blinking in the taskbar. needing clicking to bring it to the front.
I tried to get around the limitation in a myriad of ways, including getting the dispatcher of the current context, then calling OnNewWindow2 with that IDispatch object. Then I would invoke QueryInterface on the dispatch object for an IWebBrowser control. The webBrowser control (presumably under the control of the new window) could then navigate to the page of the original context. However... this too was a pretty messy solution and in the end would cause crashes.
Finally, I resorted to manually invoking JavaScript to get the desired behavior. Really?? Was there really no more elegant a solution to my problem than the below mess of code?
if ((pMsg->wParam == 'N') && (GetKeyState(VK_CONTROL) & 0x8000) && !(GetKeyState(VK_SHIFT) & 0x8000) && !(GetKeyState(VK_MENU) & 0x8000))
{
LPDISPATCH pDisp = CHtmlView::GetHtmlDocument();
IHTMLDocument2 *pDoc;
if (SUCCEEDED(pDisp->QueryInterface(IID_IHTMLDocument2, (void **)&pDoc)))
{
IHTMLWindow2* pWnd;
pDoc->get_parentWindow(&pWnd);
BSTR bStrLang = ::SysAllocString(L"JavaScript");
CString sCode(L"window.open(\"");
sCode.Append(GetLocationURL().GetBuffer());
sCode.Append(L"\");");
BSTR bStrCode = sCode.AllocSysString();
COleVariant retVal;
pWnd->execScript(bStrCode, bStrLang, retVal);
::SysFreeString(bStrLang);
::SysFreeString(bStrCode);
pDoc->Release();
}
pDisp->Release();
I find it hard to believe that I must resort to such hackery as this to get something as simple as opening a new window when the user presses Ctrl+N.
Please stackoverflow, please point out the clearly obvious thing I overlooked.
Ctrl-N in IE starts a new window on the same session. In your case, window.open or webBrowser.Navigate2 will create a window on a new session, because it will be run by iexplore.exe process which is separate from your app. The session is shared per-process, this is how the underlying UrlMon library works. So you'll loose all cookies and authentication cache for the new window. On the other hand, when you create a new window which hosts WebBrowser control within your own app process, you'll keep the session.
If such behavior is OK for your needs, try first your initial Navigate2 approach, precededing it with AllowSetForegroundWindow(ASFW_ANY) call. If the new window still doesn't receive the focus correctly, you can try creating an instance of InternetExplorer.Application out-of-proc COM object, and use the same IWebBrowser2 interface to automate it. Below is a simple C# app which works OK for me, the new window is correctly brought to the foreground, no focus issues. It should not be a problem to do the same with MFC.
using System;
using System.Runtime.InteropServices;
using System.Windows.Forms;
namespace IeApp
{
public partial class MainForm : Form
{
// get the underlying WebBrowser ActiveX object;
// this code depends on SHDocVw.dll COM interop assembly,
// generate SHDocVw.dll: "tlbimp.exe ieframe.dll",
// and add as a reference to the project
public MainForm()
{
InitializeComponent();
}
private void NewWindow_Click(object sender, EventArgs e)
{
AllowSetForegroundWindow(ASFW_ANY);
// could do: var ie = new SHDocVw.InternetExplorer()
var ie = (SHDocVw.InternetExplorer)Activator.CreateInstance(Type.GetTypeFromProgID("InternetExplorer.Application"));
ie.Visible = true;
ie.Navigate("http://www.example.com");
}
const int ASFW_ANY = -1;
[DllImport("user32.dll")]
static extern bool AllowSetForegroundWindow(int dwProcessId);
}
}

How To register a Windows Class and Find the Window using registered class

I am creating an MFC application which will be launched on click on Explorer Context (Rightclick) menu.
But I need to launch only single instance of the application. For that I have to use FindWindow and AfxRegisterClass
I tried to register the class in my MFC app as below:
BOOL CNDSClientDlg::InitInstance()
{
//Register Window Updated on 16th Nov 2010, #Subhen
// Register our unique class name that we wish to use
WNDCLASS wndcls;
memset(&wndcls, 0, sizeof(WNDCLASS));
//Class name for using FindWindow later
wndcls.lpszClassName = _T("NDSApp");
// Register new class and exit if it fails
if(!AfxRegisterClass(&wndcls)) // [C]
{
return FALSE;
}
}
and called the method in the constructor of the MFC class. I verified that the class is being registered while I am starting the application.
Now in my shell Extension I am trying to find the Class registered in my MFC as below:
CWnd *pWndPrev = NULL;
pWndPrev = CWnd::FindWindow(_T("NDSApp"),NULL);
if(pWndPrev != NULL)
pWndPrev->BringWindowToTop();
But I am not able to get the CWnd to Window. Not able to figure it out. Please let me know if I am missing something or doing something wrong.
FindWindow finds window instances not window classes. In your app which registers the class you need to actually create a window so that the extension can find that window.
(Finding the window by class name is fine; the problem is you haven't actually created anything to find.)
Also, I suspect if you try to create a window based on the window-class you've registered it will fail because you've left most of the WNDCLASS structure null. See the example you linked to for better default values. (e.g. You must provide a wndproc and hinstance.)

ActiveX HWND, DirectX WindowLess mode

I would like to render video in ActiveX control (not in pop-up DirectShow window). I have:
IID_IVMRWindowlessControl
IID_IVMRFilterConfig9
CLSID_VideoMixingRenderer9
I would like to set WindowLess mode, but I don't know how to get HWND of..., exactly, of what? IEFrame, HTML element?
hr = pWc->SetVideoClippingWindow(???);
Anyone with some hint?
Regards.
First of all, add this to the constructor of your ActiveX control:
// this seemingly innocent line is _extremely_ important.
// This causes the window for the control to be created
// otherwise, you won't get an hWnd to render to!
m_bWindowOnly = true;
Your ActiveX control will have a member variable called m_hWnd that you'll be able to use as a render target. without the m_bWindowOnly variable set true, the ActiveX control won't create its own window.
Finally, pick your renderer (VMR9 for example)
CRect rcClient;
CComPtr<IBaseFilter> spRenderer;
CComPtr<IVMRWindowlessControl9> spWindowless;
// Get the client window size
::GetClientRect(m_hWnd, rcClient);
// Get the renderer filter
spRenderer.Attach( m_pGraph->GetVideoRenderer() );
if( ! spRenderer )
return E_POINTER;
spWindowless = spRenderer;
if( spWindowless )
{
spWindowless->SetVideoClippingWindow( m_hWnd );
spWindowless->SetVideoPosition(NULL, rcClient);
spWindowless.Release();
}
spRenderer.Detach();
Please note that my graph object is a custom object and that GetVideoRenderer() is one of my own functions - it returns an IBaseFilter*.
It took me ages to find this one out. ATL is poorly documented, which is a shame, because it's an excellent technology. Anyways, hope this helps!
freefallr's info is extremely helpful, but I don't think it answers your question completely. The trick with windowless activex controls is that you don't get a window. When you draw you'll just basically get a device context and you have to respond to call from the browser and only draw when it tells you to.
The interfaces required are here: http://msdn.microsoft.com/en-us/library/ms682300%28v=VS.85%29.aspx
more info here: http://msdn.microsoft.com/en-us/library/aa751970%28VS.85%29.aspx#OC96_and_Windowless_
We've been meaning to add support for this in FireBreath (http://firebreath.org) for awhile; we have support for it in all npapi browsers, but looks like we don't (yet) support IE. If you find more details, post a summary here =]