Not able to receiving Mouse events in BHO using HTML document even

From:

=?Utf-8?B?TWljcm9kZXYx?= <Microdev1@discussions.microsoft.com>

Newsgroups:

microsoft.public.vc.atl

Date:

Mon, 8 Sep 2008 12:10:02 -0700

Message-ID:

<476531EA-560C-4F5F-B0A0-49EE2A48601C@microsoft.com>

Hi,
I am new to ATL progrmming. Based on the material in web, I have been able
to write a BHO and successfully receive Web Browser events like "Document
Complete". But I am not able to receive any HTML Document events. Here's what
I am doing to receive HTML Document events -

1) Get IID_IHTMLDocument2 document object from Browser object
2) Get IHTMLElementCollection object from IID_IHTMLDocument2 document object
3) For each object in IHTMLElementCollection object, query IID_IHTMLElement
object. (I am not able to compile the code if I try to query
"IID_IHTMLElement2")
4) Find connection point to IID_IHTMLElement object.
5) Advise the connection point to browser's document object.

For clarity, here's how I am getting browser's document object
(m_docDispatch) -

STDMETHODIMP BHOClass::Invoke(DISPID dispidMember, REFIID riid, LCID lcid,
         WORD wFlags, DISPPARAMS* pDispParams,
         VARIANT* pvarResult, EXCEPINFO* pExcepInfo,
         UINT* puArgErr)
{
IHTMLDocument2* pDoc = NULL;
if (!pDispParams)
  return E_INVALIDARG;
  //::MessageBox(NULL, "received response", "TinyBHO URL", MB_OK);
switch (dispidMember)
{
  case DISPID_DOCUMENTCOMPLETE:
  {
   CComQIPtr<IWebBrowser2, &IID_IWebBrowser2> browser =
pDispParams->rgvarg[1].pdispVal;
   if (!browser)
    break;

   IDispatch* docDispatch = NULL;
   HRESULT getDocumentResult = browser->get_Document(&docDispatch);
   if ((!SUCCEEDED(getDocumentResult)) || (!docDispatch))
    break;
   m_docDispatch = docDispatch;

And here's how step 5 is implemented -

void BHOClass::ConnectEvents(IHTMLElement* pElem)
{
HRESULT hr;
IConnectionPointContainer* pCPC = NULL;
IConnectionPoint* pCP = NULL;
DWORD dwCookie;

  // Check that this is a connectable object.
  hr = pElem->QueryInterface( IID_IConnectionPointContainer, (void**)&pCPC );
  if ( SUCCEEDED(hr) )
  {
   // Find the connection point.
   HRESULT hr = pCPC->FindConnectionPoint( DIID_HTMLElementEvents, &pCP );
   if ( SUCCEEDED(hr) )
   {
    // Advise the connection point.
    // pUnk is the IUnknown interface pointer for your event sink

    hr = pCP->Advise( m_docDispatch, &dwCookie );
    if ( SUCCEEDED(hr) )
    {
     //::MessageBox(NULL,"registering HTLM","TinyBHO",MB_OK);
     // Successfully advised
    }
    pCP->Release();
   }
   pCPC->Release();
  }
}

Please let me know what I am missing here.