FilteredFolderDlg.cpp

//////////////////////////////////////////////////////////////////////
// Custom filtering is based on Arik Poznanski's article
// C# does Shell, Part 1
// http://www.codeproject.com/csharp/csdoesshell1.asp
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "FilteredFolderDlg.h"

//////////////////////////////////////////////////////////////////////
#ifdef USE_XP_FILTRATION
//////////////////////////////////////////////////////////////////////

//////////////////////////////////////////////////////////////////////
// CFilteredFolderDialog class

CFilteredFolderDialog::CFilteredFolderDialog(LPCTSTR pszTitle,
	LPCTSTR pszSelPath,
	CWnd* pParentWnd,
	UINT	  uFlags)
	: CFolderDialog(pszTitle, pszSelPath, pParentWnd, uFlags)
	, m_pIMyFolderFilter(NULL)
	, m_pszFilter(NULL)
{
}

CFilteredFolderDialog::~CFilteredFolderDialog(VOID)
{
	// SAFE_FREE( m_pszFilter );
	// SAFE_RELEASEINTERFACE( m_pIFolderFilter )
}

VOID CFilteredFolderDialog::OnIUnknown(IN IUnknown* pIUnknown)
{
	ASSERT(pIUnknown != NULL);

	if (m_pIMyFolderFilter == NULL)
	{
		IFolderFilterSite* pIFolderFilterSite = NULL;

		HRESULT hResult = pIUnknown->QueryInterface(IID_IFolderFilterSite, (LPVOID*)&pIFolderFilterSite);
		if (SUCCEEDED(hResult))
		{
			m_pIMyFolderFilter = new IMyFolderFilter;
			ASSERT(m_pIMyFolderFilter != NULL);

			if (m_pIMyFolderFilter)
				pIFolderFilterSite->SetFilter((IUnknown*)m_pIMyFolderFilter);

			SAFE_RELEASE(pIFolderFilterSite);
		}
	}

	if (m_pIMyFolderFilter)
		m_pIMyFolderFilter->m_pszFilter = m_pszFilter;
}

VOID CFilteredFolderDialog::SetFilter(IN LPCTSTR pszFilter)
{
	ASSERT(pszFilter != NULL);

	// SAFE_FREE(m_pszFilter);
	m_pszFilter = _tcsdup(pszFilter);
}

//////////////////////////////////////////////////////////////////////
// IMyFolderFilter

IMyFolderFilter::IMyFolderFilter(VOID)
	: m_ulRef(0)
	, m_pszFilter(NULL)
{
}

STDMETHODIMP IMyFolderFilter::QueryInterface(IN     REFIID  riid,
	IN OUT LPVOID* ppvObj)
{
	ATLASSERT(ppvObj != NULL);
	if (!ppvObj)
		return (E_FAIL);

	HRESULT hResult = (E_NOINTERFACE);
	*ppvObj = NULL;

	if (IsEqualIID(riid, IID_IUnknown))
		*ppvObj = static_cast<IUnknown*>(this);
	else if (IsEqualIID(riid, IID_IFolderFilter))
		*ppvObj = static_cast<IFolderFilter*>(this);

	if (*ppvObj)
	{
		reinterpret_cast<IUnknown*>(*ppvObj)->AddRef();
		hResult = (S_OK);
	}

	return (hResult);
}

STDMETHODIMP_(ULONG) IMyFolderFilter::AddRef(VOID)
{
	return ::InterlockedIncrement((PLONG)&m_ulRef);
}

STDMETHODIMP_(ULONG) IMyFolderFilter::Release(VOID)
{
	ULONG ulNewRef = ::InterlockedDecrement((PLONG)&m_ulRef);
	if (ulNewRef <= 0)
	{
		delete this;
		return (0);
	}

	return (ulNewRef);
}

STDMETHODIMP IMyFolderFilter::ShouldShow(IN IShellFolder* pIShellFolder,
	IN LPCITEMIDLIST /*pidlFolder*/,
	IN LPCITEMIDLIST pidlItem)
{
	ASSERT(pIShellFolder != NULL);
	ASSERT(pidlItem != NULL);

	ASSERT(m_pszFilter != NULL);
	if (!m_pszFilter)
		return (E_FAIL);

	// If an item is a folder, then accept it

	LPCITEMIDLIST pidl[1] = { pidlItem };
	SFGAOF		  ulAttr = SFGAO_FOLDER;

	pIShellFolder->GetAttributesOf(1, pidl, &ulAttr);

	if ((ulAttr & SFGAO_FOLDER) == SFGAO_FOLDER)
		return (S_OK);

	// If an item is a file, then filter it

	STRRET  strRet = { 0 };
	HRESULT hResult = pIShellFolder->GetDisplayNameOf(
		pidlItem, SHGDN_NORMAL | SHGDN_FORPARSING, &strRet
	);

	if (SUCCEEDED(hResult))
	{
		LPTSTR pszDisplayName = NULL;
		hResult = ::StrRetToStr(&strRet, pidlItem, &pszDisplayName);

		if (SUCCEEDED(hResult))
		{
			hResult = (S_FALSE);

			if (::PathMatchSpec(pszDisplayName, m_pszFilter))
				hResult = (S_OK);

			SAFE_COTASKMEMFREE(pszDisplayName);
		}
	}

	return (hResult);
}

STDMETHODIMP IMyFolderFilter::GetEnumFlags(IN  IShellFolder*	/*pIShellFolder*/,
	IN  LPCITEMIDLIST	/*pidlFolder*/,
	IN  HWND*			/*phWnd*/,
	OUT LPDWORD			pdwFlags)
{
	ASSERT(pdwFlags != NULL);

	*pdwFlags = (DWORD)(SHCONTF_FOLDERS | SHCONTF_NONFOLDERS);
	return (S_OK);
}

//////////////////////////////////////////////////////////////////////
// CFolderFilter

//IMPLEMENT_DYNCREATE( CFolderFilter, CCmdTarget );
//
//BEGIN_INTERFACE_MAP( CFolderFilter, CCmdTarget )
//    INTERFACE_PART( CFolderFilter, IID_IFolderFilter, FolderFilterObj )    
//END_INTERFACE_MAP()
//
//STDMETHODIMP_( ULONG ) CFolderFilter::XFolderFilterObj::AddRef( VOID )
//{
//    METHOD_PROLOGUE( CFolderFilter, FolderFilterObj )
//    return ( pThis->ExternalAddRef() );
//}
//
//STDMETHODIMP_( ULONG ) CFolderFilter::XFolderFilterObj::Release( VOID )
//{
//    METHOD_PROLOGUE( CFolderFilter, FolderFilterObj )
//    return ( pThis->ExternalRelease() );
//}
//
//STDMETHODIMP CFolderFilter::XFolderFilterObj::QueryInterface( IN REFIID  refIid, 
//															  IN LPVOID* ppvObj )
//{
//    METHOD_PROLOGUE( CFolderFilter, FolderFilterObj )
//    return ( (HRESULT)pThis->ExternalQueryInterface( &refIid, ppvObj ) );
//}
//
//STDMETHODIMP CFolderFilter::XFolderFilterObj::ShouldShow( IN IShellFolder* pIShellFolder, 
//														  IN LPCITEMIDLIST /*pidlFolder*/, 
//														  IN LPCITEMIDLIST pidlItem )
//{
//	ASSERT( pIShellFolder != NULL );	
//	ASSERT( pidlItem	  != NULL );
//	
//	METHOD_PROLOGUE( CFolderFilter, FolderFilterObj )
//	
//	ASSERT_VALID( pThis->m_pStraFilters );
//	if( !pThis->m_pStraFilters )
//		return ( S_FALSE );
//
//	// If an item is a folder, then accept it
//
//	LPCITEMIDLIST pidl[ 1 ] = { pidlItem };
//	SFGAOF		  ulAttr	 = SFGAO_FOLDER;
//
//	pIShellFolder->GetAttributesOf( 1, pidl, &ulAttr );
//
//	if ( ( ulAttr & SFGAO_FOLDER ) ==  SFGAO_FOLDER )
//		return ( S_OK );
//
//	// If an item is a file, then filter it
//	
//	STRRET  strRet  = { 0 };
//	HRESULT hResult = pIShellFolder->GetDisplayNameOf( 
//		pidlItem, SHGDN_NORMAL | SHGDN_FORPARSING, &strRet
//	);
//
//	if( SUCCEEDED( hResult ) )
//	{	
//		LPTSTR pszDisplayName = NULL;
//		hResult = ::StrRetToStr( &strRet, pidlItem, &pszDisplayName );
//
//		if( SUCCEEDED( hResult ) )
//		{
//			LPCTSTR pszExt = ::CharNext( ::PathFindExtension( pszDisplayName ) );
//			
//			for( INT n = 0; pszExt && ( n < pThis->m_pStraFilters->GetSize() ); n++ )
//			{	
//				if( ::lstrcmpi( pszExt, pThis->m_pStraFilters->GetAt( n ) ) == 0 )
//					return ( S_OK );
//			}
//			
//			SAFE_COTASKMEMFREE( pszDisplayName );
//		}
//	}
//
//	return ( S_FALSE );
//
//}
//
//STDMETHODIMP CFolderFilter::XFolderFilterObj::GetEnumFlags( IN IShellFolder*	/*pIShellFolder*/, 
//															IN LPCITEMIDLIST	/*pidlFolder*/, 
//															IN HWND*			/*phWnd*/,
//															IN LPDWORD			pdwFlags )
//{
//	ASSERT( pdwFlags	  != NULL );	
//	//METHOD_PROLOGUE( CFolderFilter, FolderFilterObj )
//	
//	*pdwFlags = (DWORD)( SHCONTF_FOLDERS | SHCONTF_NONFOLDERS );
//	return ( S_OK );
//}

//////////////////////////////////////////////////////////////////////
#endif //USE_XP_FILTRATION
//////////////////////////////////////////////////////////////////////