C / C++ / MFC

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

3-Nov-08 15:15

as the subject.

Why do the HBITMAP be changed to black?I dont think my code have problems.
my code is as below:
app start,laod the HBITMAP from resource and store to a global HBITMAP.

then paint it on sever windows in the same process.
I found sometimes the HBITMAP was changed to black.

Could anybody meet the same issue?

Hamid_RT3-Nov-08 19:42

Hamid_RT

3-Nov-08 19:42

Did you use of WM_ERASEBKGND and can you show your code?

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

e_ilite3-Nov-08 20:44

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

3-Nov-08 20:44

BEGIN_MSG_MAP(CMyButton)
MESSAGE_HANDLER(WM_CREATE,OnCreate)
MESSAGE_HANDLER(WM_PAINT,OnPaint)
MESSAGE_HANDLER(WM_LBUTTONDOWN,OnLButtonDown)
MESSAGE_HANDLER(WM_LBUTTONUP,OnLButtonUp)
MESSAGE_HANDLER(WM_MOUSEMOVE ,OnMouseMove)
MESSAGE_HANDLER(WM_MOUSELEAVE ,OnMouseLeave)
MESSAGE_HANDLER(WM_KILLFOCUS, OnRefresh)
MESSAGE_HANDLER(WM_SETFOCUS, OnRefresh)
MESSAGE_HANDLER(BM_SETCHECK, OnStateChange)
MESSAGE_HANDLER(BM_SETSTATE, OnStateChange)
MESSAGE_HANDLER(WM_ENABLE, OnRefresh)
MESSAGE_HANDLER(WM_UPDATEUISTATE,OnRefresh)
END_MSG_MAP()

I did not use the WM_ERASEBKGND,and the system will do the default?
Need I to disable this msg?such as :
in handle WM_ERASEBKGND msg,return TRUE.

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Mark Salsbery4-Nov-08 4:42

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

4-Nov-08 4:42

Bitmaps don't just change to black by themselves.

You haven't provided anything for us to be able to help you.

How and where are you drawing the bitmap?
What is the format of the bitmap?

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

e_ilite4-Nov-08 14:01

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

4-Nov-08 14:01

Thanks your reply.Let me explain how I used the bitmap in my code.
I used WTL.
I just on WM_PAINT to draw the groupbox background use the bitmap.And I need to make the bitmap transparent.
In common ,the isssue do not duplicated.But sometimes it can be duplicated.
I posted the issue in detail here:
http://aisnote.spaces.live.com/blog/cns!5F43300FF5FC67C!161.entry[^]

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http://www.aisnote.com

Mark Salsbery5-Nov-08 4:30

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

5-Nov-08 4:30

Still no code showing how you render the bitmap... Smile | :)

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

e_ilite6-Nov-08 14:42

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

6-Nov-08 14:42

HBITMAP WINAPI ExtractSubBitmap(HBITMAP hSrcBitmap,CPoint ptStart,CPoint ptEnd)
{
HBITMAP hBitmap = NULL;

CDC srcMemDC,desMemDC;
HDC hDC = ::GetDC(0);
srcMemDC.CreateCompatibleDC(hDC);
desMemDC.CreateCompatibleDC(hDC);

srcMemDC.SelectBitmap(hSrcBitmap);
hBitmap = CreateCompatibleBitmap(hDC,ptEnd.x-ptStart.x,ptEnd.y-ptStart.y);
desMemDC.SelectBitmap(hBitmap);

desMemDC.BitBlt(0,0,ptEnd.x-ptStart.x,ptEnd.y-ptStart.y,srcMemDC,ptStart.x,ptStart.y,SRCCOPY);

ReleaseDC(0,hDC);
return hBitmap;
}

And I used the reurn hBitmap to draw.But sometimes I found the passed "HBITMAP hSrcBitmap" have been changed to black.why?

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http://www.aisnote.com

Mark Salsbery6-Nov-08 15:00

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

6-Nov-08 15:00

I've never used WTL, but generally you need to select bitmaps back out of a DC
(by restoring its previous bitmap) before using the bitmap.

Is hSrcBitmap a device dependent bitmap or a DIBSection?

Is hSrcBitmap always the same format (bits-per-pixel), and is the format compatible
with the screen?

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

e_ilite6-Nov-08 15:04

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

6-Nov-08 15:04

hSrcBitmap is just use LoadBitmap from resource and stored in
a global member so that it can be shared by some windows.

Great & Free windows software for you
http://www.aisnote.com

Mark Salsbery6-Nov-08 15:24

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

6-Nov-08 15:24

e_ilite wrote:
hSrcBitmap is just use LoadBitmap from resource

If hSrcBitmap is not a DIBSection:

hSrcBitmap has to be the same format as the screen or the SelectBitmap will fail.

What format is hSrcBitmap? 8bpp? 24bpp?

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

e_ilite6-Nov-08 15:38

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

6-Nov-08 15:38

The origin bitmap of hSrcBitmap is 24bpp.

Great & Free windows software for you
http://www.aisnote.com

Mark Salsbery6-Nov-08 16:17

Re: I loaded a bitmap from resource and share it with some windows to paint for background,but sometimes the bitmap will be changed to black?

6-Nov-08 16:17

Can you reproduce the problem consistently and debug it, like error checking
all the GDI cal return values?

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

e_ilite6-Nov-08 18:38

error C2022: '65279' : too big for character

6-Nov-08 18:38

I attached my code here:
http://www.aisnote.com/ainote/blackissue.rar[^]

Could you help to review it?
thanks in advance.

Great & Free windows software for you
http://www.aisnote.com

monsieur_jj3-Nov-08 14:51

monsieur_jj

3-Nov-08 14:51

Hi all,

I am getting an error C2022: '65279' : too big for character at the line in bold below, What should I change here? This code works if I use wsprintfW and wszBuffer is WCHAR however I need this for multibyte and must use "_T" not "L"
Any advise?

Thanks,
Jayjay

if( pRegInfo->uTaskRegID == 0 )
         {
            GUID AppGUID, TaskGUID;
            ::CoCreateGuid(&AppGUID);
            ::CoCreateGuid(&TaskGUID);
            WCHAR wszGUID[50], wszTaskGUID[50];
            ::StringFromGUID2(AppGUID, wszGUID, 50);
            ::StringFromGUID2(TaskGUID, wszTaskGUID, 50);
            TCHAR wszBuffer[1025] = { 0 };
            ::wsprintf(wszBuffer, 
               _T("\xfeff<?xml version=\"1.0\" encoding=\"UTF-16\" ?>\n")
               _T("<applications xmlns=\"http://schemas.microsoft.com/windows/cpltasks/v1\" xmlns:sh=\"http://schemas.microsoft.com/windows/tasks/v1\">")
               _T("<application id=\"%s\">")
               _T("<sh:task id=\"%s\" needsElevation=\"%s\">")
#ifdef _UNICODE
               L"<sh:name>@%s,-%ld</sh:name>"
               L"<sh:keywords>@%s,-%ld</sh:keywords>"
               L"<sh:command>%%systemroot%%\\system32\\control.exe /name %s</sh:command>"
#else
               _T("<sh:name>@%hs,-%ld</sh:name>")
               _T("<sh:keywords>@%hs,-%ld</sh:keywords>")
               _T("<sh:command>%%systemroot%%\\system32\\control.exe /name %hs</sh:command>")
#endif // _UNICODE
               _T("</sh:task>")
               _T("<category id=\"%ld\">")
               _T("<sh:task idref=\"%s\"/>")
               _T("</category>")
               _T("</application>")
               _T("</applications>"),
               wszGUID,
               wszTaskGUID,
               pRegInfo->dwRunLevel == 0 ? _T("false") : _T("true"),
               szDllName, Info.uTaskRes,
               szDllName, Info.uKeywordsRes,
               Info.pstrCanonicalName,
               pRegInfo->dwCategory,
               wszTaskGUID);
            ::wsprintf(szGUID, _T("%ws"), wszGUID);
            ::lstrcpy(szTaskFileUrl, szDllFile);
            ::wsprintf(_FindLastOf(szTaskFileUrl, '.'), _T("_cpl%d.xml"), pRegInfo->iIndex + 1);
            if( bRegister ) {
               HANDLE hFile = ::CreateFile(szTaskFileUrl, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
               if( hFile == INVALID_HANDLE_VALUE ) return HRESULT_FROM_WIN32(::GetLastError());
               DWORD dwWritten = 0;
               ::WriteFile(hFile, wszBuffer, ::lstrlen(wszBuffer) * sizeof(WCHAR), &dwWritten, NULL);
               ::CloseHandle(hFile);
            }
            else {
               ::DeleteFile(szTaskFileUrl);

Saurabh.Garg3-Nov-08 15:11

Saurabh.Garg

3-Nov-08 15:11

I don't see a bold line. Error C2022 in the documentation says, "The octal number following a backslash (\) in a character or string constant is too big to represent a character". So I am guess that you are trying to assign a number greater than 255 for a char variable.

-Saurabh

monsieur_jj3-Nov-08 15:17

monsieur_jj

3-Nov-08 15:17

Hi Saurabh,

It is this line

_T("\xfeff<?xml version=\"1.0\" encoding=\"UTF-16\" ?>\n")

Thanks,
Jayjay

Saurabh.Garg3-Nov-08 15:29

Saurabh.Garg

3-Nov-08 15:29

The first character is \xfeff which is 65279. This value cannot be stored in a char variable. I think you can split it into two characters for ANSI chars (\xfe\xff) and single char for wide-chars.

-Saurabh