Re: How to make CFileDialog, MessageBox etc ..Layered ?

From:

Scot T Brennecke <ScotB@Spamhater.MVPs.org>

Newsgroups:

microsoft.public.vc.mfc

Date:

Sat, 10 Oct 2009 01:11:56 -0500

Message-ID:

<uy0rSCXSKHA.764@TK2MSFTNGP02.phx.gbl>

Matrixinline wrote:

On Oct 7, 11:27 pm, Mikel <mikel.l...@gmail.com> wrote:

On Oct 8, 7:33 am, Matrixinline <anup.kata...@gmail.com> wrote:

Hi All,
Can you please tell me how to make CFileDialog, MessageBox, Tooltips
layered.
I tried to extend the CFileDialog and in the OnInitDialogMethod I have
written following line but it did not changed anything for it.
BOOL bTrue = ModifyStyleEx(0, WS_EX_LAYERED);
SetLayeredWindowAttributes(0,20,LWA_ALPHA);
Please let me know how to make the dialog layered.
Thanks
Anup

Well, I've never done this, but inhttp://msdn.microsoft.com/en-us/library/ms997507.aspx
you can read:
"For any layering to take place, the WS_EX_LAYERED bit needs to be
set, either at window creation time or by calling SetWindowLong with
GWL_EXSTYLE"
And gives an example:

// Set WS_EX_LAYERED on this window
SetWindowLong(hwnd, GWL_EXSTYLE,
GetWindowLong(hwnd, GWL_EXSTYLE) | WS_EX_LAYERED);
// Make this window 70% alpha
SetLayeredWindowAttributes(hwnd, 0, (255 * 70) / 100, LWA_ALPHA);

So it seems that you have to use SetWindowLong, not ModifyStyleEx, or
create it as layered. But as I said at the start, I've never done this.

No even it did not helped me.

Please let me know if I am doing wrong
Here is the code

class CMySaveAsDialog : public CFileDialog
{
public:
    CMySaveAsDialog(BOOL bOpenFileDialog,
   LPCTSTR lpszDefExt = NULL,
   LPCTSTR lpszFileName = NULL,
   DWORD dwFlags = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT,
   LPCTSTR lpszFilter = NULL,
   CWnd* pParentWnd = NULL,
   DWORD dwSize = 0
   ):CFileDialog(bOpenFileDialog,
   lpszDefExt,
   lpszFileName ,
   dwFlags ,
   lpszFilter ,
   pParentWnd ,
   dwSize )

    {};

    virtual BOOL OnInitDialog()
    {
        CFileDialog::OnInitDialog();
        BOOL bTrue = ModifyStyleEx(WS_EX_TRANSPARENT, WS_EX_LAYERED);
        SetLayeredWindowAttributes(0,20,LWA_ALPHA);

        SetWindowLong(this->m_hWnd, GWL_EXSTYLE, GetWindowLong(this->m_hWnd,
GWL_EXSTYLE) | WS_EX_LAYERED);
        // Make this window 70% alpha
        SetLayeredWindowAttributes( 0, 10, LWA_ALPHA);
        RedrawWindow( NULL, NULL, RDW_ERASE | RDW_INVALIDATE | RDW_FRAME |
RDW_ALLCHILDREN);

        return TRUE;
    };
};

Two things are important to know about CFileDialog:
1) It doesn't wrap the entire window as most dialog classes do. The common dialogs, especially the common file dialog, require
special handling, and the behavior will vary based on the OS you are targeting. http://msdn.microsoft.com/en-us/library/5fcd0hw9.aspx
http://msdn.microsoft.com/en-us/library/dk77e5e7.aspx

2) Changing things in OnInitDialog for any CDialog class (especially after the base class call) is too late to be changing such
things. You would need to hook into the window creation methods. However, in CFileDialog, because it is "special", even then it is
unlikely to be effective. Customizing the common file dialog is a very difficult thing to accomplish, and requires lots of research
and experimentation.