ID: Q179911
The information in this article applies to:
When you are creating a namespace extension that has multiple levels of folders, you may have to implement the Explore and Open commands from the context menu. This article discusses how to implement Explore and Open commands from a context menu in the Windows Explorer tree. This article assumes you are already familiar with development of namespace extensions. For additional information on writing namespace extensions, see David Campbell's article "Extending the Windows Explorer with Name Space Extensions" in the July, 1996 issue of the Microsoft Systems Journal. In addition, please see the following article in the Microsoft Knowledge Base:
ARTICLE-ID: Q178665
TITLE : SAMPLE: RegView.exe: Shell Namespace Extension Example
When you want to implement Explore and Open commands from your shell view, normally you will call IShellBrowser::BrowseObject, specifying the proper options for the desired commands. But you cannot do this for your folder items in the Windows Explorer tree because the IShellBrowser interface is not always available to use. Fortunately, you can implement these commands using ShellExecuteEx and these commands can be used by both the shell folder and shell view implementations.
If you want to implement Explore and Open commands in the context menus for your items in the Windows Explorer tree, you must first add these items to the menu in your IContextMenu::QueryContextMenu. Because you will be handling the execution of the commands, you can supply any command ID for the menu items that you want. Remember that the Explore and Open menu strings should be localized for use with other languages.
The first challenge is how to determine which item should be the default item. Normally, if the item is displayed in Explore mode (a window that contains a tree), the Explore command is the default. If the item is displayed in Open mode (no tree present), then Open is the default item in the context menu. If the context menu is being generated by the shell from a Explore mode window, it will set the CMF_EXPLORE flag when it calls your IContextMenu::QueryContextMenu. If this flag is set, you should make Explore the first and default item in the menu. If this flag is not set, then you should make Open the first and default item.
Following is an example of how you may accomplish this:
#define IDM_EXPLORE 0
#define IDM_OPEN 1
#define IDM_LAST IDM_OPEN
STDMETHODIMP CContextMenu::QueryContextMenu( HMENU hMenu,
UINT indexMenu,
UINT idCmdFirst,
UINT idCmdLast,
UINT uFlags)
{
if(!(CMF_DEFAULTONLY & uFlags))
{
MENUITEMINFO mii;
if(uFlags & CMF_EXPLORE)
{
//add the Explore command first and make it the default item
ZeroMemory(&mii, sizeof(mii));
mii.cbSize = sizeof(mii);
mii.fMask = MIIM_ID | MIIM_TYPE | MIIM_STATE;
mii.wID = idCmdFirst + IDM_EXPLORE;
mii.fType = MFT_STRING;
mii.dwTypeData = TEXT("&Explore");
mii.fState = MFS_ENABLED | MFS_DEFAULT;
InsertMenuItem( hMenu,
indexMenu++,
TRUE,
&mii);
ZeroMemory(&mii, sizeof(mii));
mii.cbSize = sizeof(mii);
mii.fMask = MIIM_ID | MIIM_TYPE | MIIM_STATE;
mii.wID = idCmdFirst + IDM_OPEN;
mii.fType = MFT_STRING;
mii.dwTypeData = TEXT("&Open");
mii.fState = MFS_ENABLED;
InsertMenuItem( hMenu,
indexMenu++,
TRUE,
&mii);
}
else
{
//add the Open command first and make it the default item
ZeroMemory(&mii, sizeof(mii));
mii.cbSize = sizeof(mii);
mii.fMask = MIIM_ID | MIIM_TYPE | MIIM_STATE;
mii.wID = idCmdFirst + IDM_OPEN;
mii.fType = MFT_STRING;
mii.dwTypeData = TEXT("&Open");
mii.fState = MFS_ENABLED | MFS_DEFAULT;
InsertMenuItem( hMenu,
indexMenu++,
TRUE,
&mii);
ZeroMemory(&mii, sizeof(mii));
mii.cbSize = sizeof(mii);
mii.fMask = MIIM_ID | MIIM_TYPE | MIIM_STATE;
mii.wID = idCmdFirst + IDM_EXPLORE;
mii.fType = MFT_STRING;
mii.dwTypeData = TEXT("&Explore");
mii.fState = MFS_ENABLED;
InsertMenuItem( hMenu,
indexMenu++,
TRUE,
&mii);
}
return MAKE_HRESULT(SEVERITY_SUCCESS, 0, USHORT(IDM_LAST + 1));
}
return MAKE_HRESULT(SEVERITY_SUCCESS, 0, USHORT(0));
}
Following is an example that obtains the context menu for the specified items in a view. The view object maintains the IShellFolder interface of the folder that created it in m_pSFParent.
#define MENU_OFFSET 1
#define MENU_MAX 100
HMENU CShellView::GetContextMenuForItems( UINT uItems,
LPITEMIDLIST *aItems)
{
HMENU hMenu;
if(aItems)
{
LPCONTEXTMENU pContextMenu = NULL;
m_pSFParent->GetUIObjectOf( m_hwndParent,
uItems,
(LPCITEMIDLIST*)aItems,
IID_IContextMenu,
NULL,
(LPVOID*)&pContextMenu);
if(pContextMenu)
{
HMENU hMenu = CreatePopupMenu();
/*
See if we are in Explore or Open mode. If the browser's tree is
present, then we are in Explore mode.
*/
BOOL fExplore = FALSE;
HWND hwndTree = NULL;
if(SUCCEEDED(m_pShellBrowser->GetControlWindow(FCW_TREE,
&hwndTree)) && hwndTree)
{
fExplore = TRUE;
}
if(hMenu && SUCCEEDED(pContextMenu->QueryContextMenu( hMenu,
0,
MENU_OFFSET,
MENU_MAX,
CMF_NORMAL | (fExplore ? CMF_EXPLORE : 0))))
{
}
else
{
DestroyMenu(hMenu);
hMenu = NULL;
}
}
}
return hMenu;
}
1. Specify the SEE_MASK_IDLIST flag and pass a fully-qualified PIDL for the
item to be opened or explored.
"folder."
attempt to establish a DDE conversation with this window if the folder
should be browsed in the same window. If you are calling InvokeCommand
from a shell view, you should pass the view's parent window handle. This
is usually obtained in IShellView::CreateViewWindow by calling the
IShellBrowser::GetWindow method.
command.
Following is an example of how this is performed:
STDMETHODIMP CContextMenu::InvokeCommand(LPCMINVOKECOMMANDINFO lpcmi)
{
if(HIWORD(lpcmi->lpVerb))
{
//the command is being sent via a verb
return NOERROR;
}
if(LOWORD(lpcmi->lpVerb) > IDM_LAST)
return E_INVALIDARG;
switch(LOWORD(lpcmi->lpVerb))
{
case IDM_EXPLORE:
case IDM_OPEN:
{
LPITEMIDLIST pidlFQ;
SHELLEXECUTEINFO sei;
/*
Only one PIDL can be passed to ShellExecuteEx, so default to the
first one in the list.
*/
pidlFQ = CreateFullyQualifiedPidl(m_aPidls[0]);
ZeroMemory(&sei, sizeof(sei));
sei.cbSize = sizeof(sei);
sei.fMask = SEE_MASK_IDLIST | SEE_MASK_CLASSNAME;
sei.lpIDList = pidlFQ;
sei.lpClass = TEXT("folder");
sei.hwnd = lpcmi->hwnd;
sei.nShow = SW_SHOWNORMAL;
if(LOWORD(lpcmi->lpVerb) == IDM_EXPLORE)
sei.lpVerb = TEXT("explore");
else
sei.lpVerb = TEXT("open");
ShellExecuteEx(&sei);
DeletePidl(pidlFQ);
}
break;
}
return NOERROR;
}
Microsoft Systems Journal, July 1996, "Extending the Windows Explorer with Name Space Extensions," page 41, David Campbell
For additional information, please see the following article in the Microsoft Knowledge Base:
ARTICLE-ID: Q178665
TITLE : SAMPLE: RegView.exe: Shell Namespace Extension Example
Keywords : kbcode kbExtension kbNameSpace kbNTOS400 kbWinOS2000 kbWinOS95 kbWinOS98 kbGrpShell
Issue type : kbhowtoLast Reviewed: December 25, 1998