C / C++ / MFC

22-Jun-02 21:30

Hi.

In both windows and dialog boxes, there are buttons on the upper right corner of the frame to minimize, maximize, and/or close window. Is it possible to enable or disable one or more of those buttons? For example, I would like to disable the maximize option during a certain time and then reenable it.

Thanks,
Kuphryn

Nish Nishant22-Jun-02 22:12

Nish Nishant

22-Jun-02 22:12

SetWindowLong(this->m_hWnd,GWL_STYLE,
    GetWindowLong(m_hWnd,GWL_STYLE) & ~WS_MAXIMIZEBOX);

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

valikac23-Jun-02 6:39

23-Jun-02 6:39

Nice! Thanks.

How about the close window, big "X" icon? Is there a way to disable it too and/or catches it because the program closes or the dialog closes?

Kuphryn

Sonu Kapoor23-Jun-02 7:30

Sonu Kapoor

23-Jun-02 7:30

hi,

hm....sorry cound find how to disable the "X" button, but it think you can catch, whether the dialog closes or not. Put the WM_CLOSE handler to your Dialog class and put the code in that you need. This will always tell you when the dialog is closing!

for example:
void CCloseDDlg::OnClose()
{
MessageBox("Closing the app");
CDialog::OnClose();
}

Regards, Sonu

valikac23-Jun-02 7:38

23-Jun-02 7:38

Thanks.

Perfect! That solution is exactly what I will implement if it is not possible t disable the "X" in the window frame and/or dialog box frame.

Kuphryn

Nish Nishant23-Jun-02 15:25

Nish Nishant

23-Jun-02 15:25

Hello

As Sonu has said you can override OnClose(), but if you actually want to disable the close button, use this code

GetSystemMenu(FALSE)->RemoveMenu(SC_CLOSE,MF_BYCOMMAND);

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

valikac23-Jun-02 16:16

Problem with GetDIBits under XP/NT

23-Jun-02 16:16

Nice!!! Thanks!

I tried our solution. I was able to disable the "X," but could not recover it. Through looking up some other functions via help, I found another solution.

-----
// Disable the "X"
GetSystemMenu(FALSE)->EnableMenuItem(SC_CLOSE,MF_DISABLED);

// Enable the "X"
GetSystemMenu(FALSE)->EnableMenuItem(SC_CLOSE,MF_ENABLED);
-----

Furthermore, SC_CLOSE is just one of a series of menu items that can be used.

GetSystemMenu() is very powerful. Thanks!

Kuphryn

yarp22-Jun-02 21:00

22-Jun-02 21:00

I've been using the ::GetDIBits function to convert from HBitmap to DIB in a thumbnailer I'm writing. The idea is to use GetDIBits to convert from any bitmap format to a 32 bpp DIB. I then render the DIB to the screen with ::StrechDiBits.
The code below works fine with W98/WMe but under W2k/XP it sometimes - very often - render transparent bitmaps. I wonder if this a bug from me or a bug from the driver of my video card (ATI Radeon DDR 64), but I got the same problem on another XP machine.
Can anybody tell me if there's something wrong in the code below ? Personnaly I give up, I tried so many things I've no more idea.
1/ We get a HBitmap from Disk
2/ Prepare for our final DIB header (pBMI)
3/ Get bitmaps bits (GetDiBits)
4/ Save the bits in a buffer from our Image class (m_pBits)

void __fastcall CP3dOBmp::CreateFromHBitmap(HBITMAP hBitmap, int Width, int Height)
{
HANDLE hDib;
BITMAPINFO* pBMI;
HDC hDC = ::GetDC(NULL);

// Get bitmap format
//::GetDIBits(hDC, hBitmap, 0, 0, NULL, pBMI, DIB_RGB_COLORS);

Create(Width, Height, 32);

int nMem = sizeof(BITMAPINFOHEADER) +
(((((Width * 32) + 31) & ~31) >> 3) * Height);
hDib = GlobalAlloc(GHND, nMem);
if (!hDib) return;

pBMI = (BITMAPINFO *)GlobalLock(hDib);
BITMAPINFOHEADER* pBIH = (BITMAPINFOHEADER *)pBMI;
pBIH->biSize = sizeof(BITMAPINFOHEADER);
pBIH->biWidth = Width;
pBIH->biHeight = Height;
pBIH->biPlanes = 1;
pBIH->biBitCount = 32;
pBIH->biCompression = BI_RGB;
pBIH->biSizeImage = ((((Width * 32) + 31) & ~31) >> 3) * Height;
pBIH->biXPelsPerMeter = 0;
pBIH->biYPelsPerMeter = 0;
pBIH->biClrUsed = 0;
pBIH->biClrImportant = 0;

// Get hBitmap data
if (::GetDIBits(hDC, hBitmap, 0, Height,
(LPBYTE)pBMI->bmiColors, // Pointer to the bits
pBMI,
DIB_RGB_COLORS)) {
memcpy(m_pBits, (LPBYTE)pBMI->bmiColors, (32/8)*Width*Height);
}

GlobalUnlock(hDib);
GlobalFree(hDib);

::ReleaseDC(NULL, hDC);
}

The GetDiBits function obviously returns a blank buffer as I don't initialize the m_pBits one and I get a transaprent bitmap.
Good luck Wink | ;)

)

Yarp

Joel Lucsy23-Jun-02 16:26

Joel Lucsy

23-Jun-02 16:26

Try using a BITMAPV4HEADER instead of a BITMAPINFOHEADER. I had the reverse problem. I had code working under XP, but failed under 95/98. If nothing else it's worth a shot.

Joel Lucsy (jjlucsy@ameritech.net)

yarp23-Jun-02 18:59

23-Jun-02 18:59

I can try this, I tried nearly hundrer solutions this weekend.

I think the problem comes from a memory management difference between XP and W98. I should probably lock something somewhere.

I'll tell you here, if I got the fix.

Yarp

yarp24-Jun-02 8:03

24-Jun-02 8:03

I found - at last - that the reason why it doesn't work is that the bitmap (HBITMAP) must not be selected in a device context before to proceed. Otherwise the code is good.
I tried with a BITMAPV4HEADER but I couldn't find the way to call GetDiBits properly and gave up, so I don't know if it would have solve the problem but I guess not.
Tonight I am happy Wink | ;)

Cheers,

Yarp

Mike Nordell23-Jun-02 17:22

Mike Nordell

23-Jun-02 17:22

The idea is to use GetDIBits to convert from any bitmap format to a 32 bpp DIB.

That seems like a very slow way of creating a 32-bpp DIB compared to using CreateDibSection() and just blitting the source to the created bitmap. Just call GetObject to get the bits later on.

yarp23-Jun-02 18:56