🚀 go-pugleaf

Mike Collins wrote:

>Hi all, can anyone point me in the right direction with this -not sure if it 
>is possible though.

Sounds COMplicated but doable.
(I haven't done it, just reading the docs...)

>I 'm using the SHBrowseForFolder api to display a browser dialog.  However, 
>i want to control what is displayed, and thus selected within this dialog. 
>I want to limit the users display to only removale drives, CD / DVD drives 
>and folders within these drives.  I've coded a custome callback for the 
>browser but i'm not sure what messages to look for and how to process then.

The remarks section here
http://msdn2.microsoft.com/en-us/library/ms647664.aspx
mentions  Custom Filtering (with 6 steps)

Step3
You will be catching BFFM_IUNKNOWN message in your callback
http://msdn2.microsoft.com/en-us/library/ms649522.aspx

    case BFFM_IUNKNOWN:
	IFolderFilterSite* FFS;
	((IUnknown*)lParam)->QueryInterface( Unsure, &FFS );

Step 5
Then making your COM filter interface available to the dialog.
http://msdn2.microsoft.com/en-us/library/ms645491.aspx

	FFS->SetFilter( MyIUnknownCOMInterfaceThatHasAnIFolderFilter);
Step 6
	FFS->Release();

Step 4
You would then need a COM Interface 
(MyIUnknownCOMInterfaceThatHasAnIFolderFilter) that returns a pointer
to an IFolderFilter which implements your 2 filtering procs.
http://msdn2.microsoft.com/en-us/library/ms645494.aspx

In particular your  IFolderFilter::ShouldShow() method returns S_OK to
show and S_FALSE to hide.
http://msdn2.microsoft.com/en-us/library/ms645496.aspx

Apparently after all that, the dialog automatically calls your COM
filters for each item.

COM interfaces are currently beyond my knowledge base.
Perhaps you have ventured there?

"Mike Collins" <its@TheBottomOfThePost.com> wrote in message
news:45c9eb0a@newsgroups.borland.com...

> I want to limit the users display to only removale drives, CD / DVD
> drives and folders within these drives.

SHBrowseForFolder() does not support that.  You can use the pidlRoot
member of the BROWSEINFO structure to limit the dialog to drive
letters only by setting it to the ITEMIDLIST returned by
SHGetSpecialFolderLocation(CSIDL_DRIVES).  But you cannot filter out
which individual drives are actually displayed.  The only thing you
can do is use the callback function to prevent the dialog from being
closed if the user tries to select an incorrect drive/folder.

> I've coded a custome callback for the browser but i'm not sure what
> messages to look for and how to process then.

For example:

    int CALLBACK BrowseCallbackProc(HWND hwnd, UINT uMsg, LPARAM
lParam, LPARAM lpData)
    {
        if( uMsg == BFFM_SELCHANGED )
        {
            LPITEMIDLIST pidl = (LPITEMIDLIST) lpData;
            TCHAR path[MAX_PATH+1] = {0};

            if( SHGetPathFromIDList(pidl, path) )
            {
                if( path[1] == TEXT(':') )
                {
                    path[2] = 0;

                    UINT type = GetDriveType(path);
                    if( (type == DRIVE_REMOVABLE) || (type ==
DRIVE_CDROM) )
                    {
                        SendMessage(hwnd, BFFM_ENABLEOK, TRUE, 0);
                        SendMessage(hwnd, BFFM_SETSTATUSTEXT, 0,
(LPARAM) TEXT(""));
                        return 0;
                    }
            }

            SendMessage(hwnd, BFFM_ENABLEOK, FALSE, 0);
            SendMessage(hwnd, BFFM_SETSTATUSTEXT, 0, (LPARAM)
TEXT("Select a removable drive/folder only!"));
        }

        return 0;
    }

    void __fastcall TForm1::Button1Click(TObject *Sender)
    {
        TCHAR buffer[MAX_PATH+1];

        LPITEMIDLIST pidlRoot = NULL;
        SHGetSpecialFolderLocation(Handle, CSIDL_DRIVES, &pidlRoot);

        BROWSEINFO bi = {0};
        bi.hwndOwner = Handle;
        bi.pidlRoot = pidlRoot;
        bi.pszDisplayName = buffer;
        bi.lpszTitle = TEXT("Select a removalbe drive/folder");
        bi.ulFlags = BIF_STATUSTEXT | BIF_RETURNONLYFSDIRS;
        bi.lpfn = &BrowseCallbackProc;

        LPITEMIDLIST pidl = SHBrowseForFolder(&bi);
        if( pidlRoot ) CoTaskMemFree(pidlRoot);

        if( pidl )
        {
            //...
            CoTaskMemFree(pidl);
        }
    }


Gambit

"Bob Gonder" <notbg@notmindspring.invalid> wrote in message
news:6f0ks2166gv2qvl1v7oq0kofrmitcu4mio@4ax.com...

> The remarks section here
> http://msdn2.microsoft.com/en-us/library/ms647664.aspx
> mentions  Custom Filtering (with 6 steps)

I stand corrected.  I never noticed that Microsoft added filtering to
the dialog in XP.  In which case, my earlier example then becomes
something like the following instead:

    #include <shobjidl.h>

    class MyFilter : public IFolderFilter
    {
    private:
        ULONG mRef;
    public:
        MyFilter()
            : mRef(0)
        {
        }

        HRESULT __stdcall QueryInterface(const REFIID riid, void**
ppv)
        {
            if( !ppv )
                return E_POINTER;

            *ppv = NULL;

            if( riid == IID_IUnknown )
                *ppv = (IUnknown*) this;
            else if( riid == IID_IFolderFilter )
                *ppv = (IFolderFilter*) this;

            if( *ppv == NULL )
                return E_NOINTERFACE;

            AddRef();
            return S_OK;
        }

        ULONG __stdcall AddRef()
        {
            return ++mRef;
        }

        ULONG __stdcall Release()
        {
            if( --mRef > 0 )
                return mRef;

            delete this;
            return 0;
        }

        HRESULT __stdcall GetEnumFlags(IShellFolder *psf,
PCIDLIST_ABSOLUTE pidlFolder, HWND *phwnd, DWORD *pgrfFlags)
        {
            *pgrfFlags = SHCONTF_FOLDERS;
            return S_OK;
        }

        HRESULT __stdcall ShouldShow(IShellFolder *psf,
PCIDLIST_ABSOLUTE pidlFolder, PCUITEMID_CHILD pidlItem)
        {
            ULONG attrs = 0;
            psf->GetAttributesOf(1, &pidlFolder, &attrs);

            if( (attrs & SFGAO_FILESYSTEM) && (attrs &
SFGAO_REMOVABLE) )
                return S_OK;

            return S_FALSE;
        }
    };

    #ifndef BFFM_IUNKNOWN
    #define BFFM_IUNKNOWN 5
    #endif

    int CALLBACK FilterCallbackProc(HWND hwnd, UINT uMsg, LPARAM
lParam, LPARAM lpData)
    {
        if( uMsg == BFFM_IUNKNOWN )
        {
            IFolderFilterSite *pSite = NULL;
            ((IUnknown*)
lParam)->QueryInterface(IID_IFolderFilterSite, (void**)&pSite);

            MyFilter *filter = new MyFilter;
            if( FAILED(pSite->SetFilter(filter)) )
                delete filter;
            pSite->Release();
        }

        return 0;
    }

    int CALLBACK FolderCallbackProc(HWND hwnd, UINT uMsg, LPARAM
lParam, LPARAM lpData)
    {
        if( uMsg == BFFM_SELCHANGED )
        {
            LPITEMIDLIST pidl = (LPITEMIDLIST) lpData;
            TCHAR path[MAX_PATH+1] = {0};

            if( SHGetPathFromIDList(pidl, path) )
            {
                if( path[1] == TEXT(':') )
                {
                    path[2] = 0;

                    UINT type = GetDriveType(path);
                    if( (type == DRIVE_REMOVABLE) || (type ==
DRIVE_CDROM) )
                    {
                        SendMessage(hwnd, BFFM_ENABLEOK, TRUE, 0);
                        SendMessage(hwnd, BFFM_SETSTATUSTEXT, 0,
(LPARAM) TEXT(""));
                        return 0;
                    }
                }
            }

            SendMessage(hwnd, BFFM_ENABLEOK, FALSE, 0);
            SendMessage(hwnd, BFFM_SETSTATUSTEXT, 0, (LPARAM)
TEXT("Select a removable drive/folder only!"));
        }

        return 0;
    }

    void __fastcall TForm1::Button1Click(TObject *Sender)
    {
        TCHAR buffer[MAX_PATH+1];

        LPITEMIDLIST pidlRoot = NULL;
        SHGetSpecialFolderLocation(Handle, CSIDL_DRIVES, &pidlRoot);

        BROWSEINFO bi = {0};
        bi.hwndOwner = Handle;
        bi.pidlRoot = pidlRoot;
        bi.pszDisplayName = buffer;
        bi.lpszTitle = TEXT("Select a removable drive/folder");
        bi.ulFlags = BIF_NEWDIALOGSTYLE | BIF_RETURNONLYFSDIRS;

        if( (Win32Platform != VER_PLATFORM_WIN32_NT) ||
(Win32MajorVersion < 5) || ((Win32MajorVersion == 5) &&
(Win32MinorVersion < 1)) )
        {
            bi.lpfn = &FolderCallbackProc;
            bi.ulFlags |= BIF_STATUSTEXT;
        }
        else
            bi.lpfn = &FilterCallbackProc;

        LPITEMIDLIST pidl = SHBrowseForFolder(&bi);
        if( pidlRoot ) CoTaskMemFree(pidlRoot);

        if( pidl )
        {
            //...
            CoTaskMemFree(pidl);
        }
    }


Gambit

Cheers bob, i had looked at the MSDN references that you so kindly posted 
below and they scare the s&%t out of me - was naively hoping that someone 
would tell me that it was all that complicated - but alas.

I actual ended up doing it as remy suggested by processing the users 
selection on the fly and then disallowing the OK button and setting the 
status text

Thanks again - might brave it when i'm not so busy.

Mike

"Bob Gonder" <notbg@notmindspring.invalid> wrote in message 
news:6f0ks2166gv2qvl1v7oq0kofrmitcu4mio@4ax.com...
> Mike Collins wrote:
>
>>Hi all, can anyone point me in the right direction with this -not sure if 
>>it
>>is possible though.
>
> Sounds COMplicated but doable.
> (I haven't done it, just reading the docs...)
>
>>I 'm using the SHBrowseForFolder api to display a browser dialog. 
>>However,
>>i want to control what is displayed, and thus selected within this dialog.
>>I want to limit the users display to only removale drives, CD / DVD drives
>>and folders within these drives.  I've coded a custome callback for the
>>browser but i'm not sure what messages to look for and how to process 
>>then.
>
> The remarks section here
> http://msdn2.microsoft.com/en-us/library/ms647664.aspx
> mentions  Custom Filtering (with 6 steps)
>
> Step3
> You will be catching BFFM_IUNKNOWN message in your callback
> http://msdn2.microsoft.com/en-us/library/ms649522.aspx
>
>    case BFFM_IUNKNOWN:
> IFolderFilterSite* FFS;
> ((IUnknown*)lParam)->QueryInterface( Unsure, &FFS );
>
> Step 5
> Then making your COM filter interface available to the dialog.
> http://msdn2.microsoft.com/en-us/library/ms645491.aspx
>
> FFS->SetFilter( MyIUnknownCOMInterfaceThatHasAnIFolderFilter);
> Step 6
> FFS->Release();
>
> Step 4
> You would then need a COM Interface
> (MyIUnknownCOMInterfaceThatHasAnIFolderFilter) that returns a pointer
> to an IFolderFilter which implements your 2 filtering procs.
> http://msdn2.microsoft.com/en-us/library/ms645494.aspx
>
> In particular your  IFolderFilter::ShouldShow() method returns S_OK to
> show and S_FALSE to hide.
> http://msdn2.microsoft.com/en-us/library/ms645496.aspx
>
> Apparently after all that, the dialog automatically calls your COM
> filters for each item.
>
> COM interfaces are currently beyond my knowledge base.
> Perhaps you have ventured there?
>
> 

Bingo - exactly how i did it in then end - thats for the suggestion though - 
com filters were too scarey


"Remy Lebeau (TeamB)" <no.spam@no.spam.com> wrote in message 
news:45ca1a14$1@newsgroups.borland.com...
>
> "Mike Collins" <its@TheBottomOfThePost.com> wrote in message
> news:45c9eb0a@newsgroups.borland.com...
>
>> I want to limit the users display to only removale drives, CD / DVD
>> drives and folders within these drives.