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Re: Failed to initialize COM library error

CPallini14-Dec-09 1:38

14-Dec-09 1:38

You should check better the function return value (make your program reporting it). See the documentation for details [^].
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Re: Failed to initialize COM library error

Durga_Devi14-Dec-09 2:07

Durga_Devi

14-Dec-09 2:07

HI,

For the function CoInitializeEx(), dont check for the returned code.
Because if the COM has been initialized on the calling thread, the return code will be failed i.e S_FALSE.
Just call the CoInitializeEx() and proceed to next.

Re: Failed to initialize COM library error

CPallini14-Dec-09 2:17

CPallini

14-Dec-09 2:17

DurgaDevi_hr wrote:
For the function CoInitializeEx(), dont check for the returned code.
Because if the COM has been initialized on the calling thread, the return code will be failed i.e S_FALSE.

Your point is wrong.

In fact, CoInitializeEx() may return S_FALSE the way you depicted. However FAILED(S_FALSE) evaluates to false.
Smile | :)

Re: Failed to initialize COM library error

transoft14-Dec-09 3:59

transoft

14-Dec-09 3:59

Did you register COM in the new machine?

Using following function always successes for me.

hr = CoCreateInstance( CLSID_App, NULL, CLSCTX_INPROC_SERVER, IID_IUnknown, (void **) &pUnk );

DrawText

kumar sanghvi14-Dec-09 0:32

kumar sanghvi

14-Dec-09 0:32

Hi,
Im trying to draw text on a button which is placed on a Dialog...using the below code in Onpaint

CWnd* pWnd = GetDlgItem(IDC_BUTTON1);
CDC* pDC = pWnd->GetDC();
CRect rect1(3,5,8,10);
pDC->SetTextColor(::GetSysColor(COLOR_HIGHLIGHTTEXT));
pDC->SetBkColor(::GetSysColor(COLOR_HIGHLIGHT));
CBrush brush(RGB(0,0,64));
pDC->SelectObject(&brush);
pDC->DrawText(_T("Example"),&rect1,DT_LEFT|DT_SINGLELINE|DT_VCENTER);
CDialog::OnPaint();

but the above code doesn"t reflect the text...
pls correct me...

Re: DrawText

CPallini14-Dec-09 0:42

CPallini

14-Dec-09 0:42

Yout cannot do that, that way. See, for instance [^].
Smile | :)

Re: DrawText

kumar sanghvi14-Dec-09 0:54

kumar sanghvi

14-Dec-09 0:54

Thanks for ur Reply...but the button control is from Resource not a custom Control....
Is it not possible to draw text on a control which is created from resource..?

Re: DrawText

CPallini14-Dec-09 0:59

CPallini

14-Dec-09 0:59

Usually the button is loaded from resource (where is stored with BS_OWNERDRAW style).
Smile | :)

Re: DrawText

kumar sanghvi14-Dec-09 1:02

kumar sanghvi

14-Dec-09 1:02

If Possible can u explain in more detail..i didn"t get the point..

Re: DrawText

CPallini14-Dec-09 1:29

CPallini

14-Dec-09 1:29

If you're using MFC, this article [^] (from the competitors... Roll eyes | :rolleyes:

) may help.
Smile | :)

DSN Creation through SQLConfigDataSource() funciton

Durga_Devi14-Dec-09 0:17

Durga_Devi

14-Dec-09 0:17

Hi,

The following sample failed to create the DSN,
void main()
{
//As my DB path will change frequently i am using this method.
bool aDSNCreated = false;
char temp[MAX_PATH];
sprintf(temp,"DSN=SAMPLE\0DBQ=D:\\SAMPLE.mdb\0");

aDSNCreated = SQLConfigDataSource(NULL, ODBC_ADD_SYS_DSN, "Microsoft Access Driver (*.mdb)\0", temp);
printf("%d",aDSNCreated );
}

whereas when I execute the below code; it execute successfully.Can anyone help in this why its happening?

void main()
{
bool aDSNCreated = false;

aDSNCreated = SQLConfigDataSource(NULL, ODBC_ADD_SYS_DSN, "Microsoft Access Driver(*.mdb)\0","DSN=SAMPLE\0DBQ=D:\\SAMPLE.mdb\0");
printf("%d",aDSNCreated );
}

Re: DSN Creation through SQLConfigDataSource() funciton

Moak14-Dec-09 0:46

Moak

14-Dec-09 0:46

DurgaDevi_hr wrote:
"Microsoft Access Driver(*.mdb)\0","DSN=SAMPLE\0DBQ=D:\\SAMPLE.mdb\0"

Interesting string format with a double Null-Terminator[^], what were they thinking?

The extra Null-Terminator will cause problems with most C-Runtime string functions.
Have a look at SQLConfigDataSource attributes with variables[^], does this help?

/M

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Re: DSN Creation through SQLConfigDataSource() funciton

Durga_Devi14-Dec-09 1:14

Durga_Devi

14-Dec-09 1:14

Hi Moak,
I tried the logic as specified in the link.

It worked fine. Thanks for that.

But can u tell me, why SQLConfigDataSource() parameter alone is accepting the null terminator string?
Any idea about that? Smile | :)

Re: DSN Creation through SQLConfigDataSource() funciton [modified]

Moak14-Dec-09 1:47

Moak

14-Dec-09 1:47

DurgaDevi_hr wrote:
But can u tell me, why SQLConfigDataSource() parameter alone is accepting the null terminator string?

In a nutshell, the SQLConfigDataSource() uses a strange string format and with a literal text string this is fortunately not a problem (your second example code). But when you use string functions such as sprintf/strcpy/strlen they will stop at the first Null-Terminator. For example "bla\0fasel\0" would be copied only to the the first \0 and becomes "bla\0". You can try it in the debugger. Smile | :)

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modified on Monday, December 14, 2009 7:53 AM

Re: DSN Creation through SQLConfigDataSource() funciton

Durga_Devi14-Dec-09 1:59

Durga_Devi

14-Dec-09 1:59

Tanx for ur reply!!

Re: DSN Creation through SQLConfigDataSource() funciton

David Crow15-Dec-09 3:14

David Crow

15-Dec-09 3:14

DurgaDevi_hr wrote:
The following sample failed to create the DSN,

So then why aren't you calling SQLInstallerError() to find out why?

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Controls are erased when dragging a dialog

m_mun14-Dec-09 0:15

m_mun

14-Dec-09 0:15

Hi all,

I have developed a SDI. It is divided into two parts using a splitter i)simple view ii) another is a dialog(derived from CFormView).
My problem is, whenever i resizing the dialog, all static text and controls are erased and redrawing. How can i stop it?

Thanks to all

Re: Controls are erased when dragging a dialog

Sarath C14-Dec-09 2:30

Sarath C

14-Dec-09 2:30

can you try WS_CLIPCHILDREN[^] style?

-Sarath.

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Multiple Documents, CView class - Color change

Paulraj G13-Dec-09 22:36

Paulraj G

13-Dec-09 22:36

Hi...

I am doing a MFC Applicaton.
That is Multiple Document and Base class is CView Class. While i am running the program a white color window is opening. I need to change the white colour window to Block colour window.

Any one have idea, how to convert the window color?

Any help will be appreciated.

Thanks...

G.Paulraj

Re: Multiple Documents, CView class - Color change

Emilio Garavaglia13-Dec-09 22:53

Emilio Garavaglia

13-Dec-09 22:53

Create a "Black Brush" that leave like the window (for example, make it a member of your View class) and retun its handle responding to the WM_ERASEBKGND message.

2 bugs found.
> recompile ...
65534 bugs found.
D'Oh! | :doh:

Re: Multiple Documents, CView class - Color change

Paulraj G13-Dec-09 23:00

Paulraj G

13-Dec-09 23:00

where i have to erase? in OnDraw() method?

G.Paulraj

Re: Multiple Documents, CView class - Color change

Emilio Garavaglia15-Dec-09 5:03

Emilio Garavaglia

15-Dec-09 5:03

Paulraj G wrote:
where i have to erase?

Er ... no. You don't "have to": windows does this before calling WM_PAINT that's handled by MFC via OnDraw().
And does this using the brush that is returned by the WM_ERASEBKGD message, that - by default - is the brush of the WINDOWCLASSEXW structure registered by MFC when creating the very first window ... that is -in turn- the brush returned by GetSysColorBrush(COLOR_WINDOW) that's usually white.

Now, if you have another brush (whatever color or pattern you like) and you trap the WM_ERASEBKGD message (just add the appropriate ON_MESSAGE macro in the message map and define a congruent function) returning your brush, widows will erase with it, and than will call OnDraw().

2 bugs found.
> recompile ...
65534 bugs found.
D'Oh! | :doh:

Re: Multiple Documents, CView class - Color change

Richard MacCutchan13-Dec-09 23:11

Richard MacCutchan

13-Dec-09 23:11

I think you need to set this as the background brush either when your View class is registered (not sure how this is done in MFC but I guess you can find out) or perhaps in the OnCreate() override.

Bitmap

kumar sanghvi13-Dec-09 21:59

kumar sanghvi

13-Dec-09 21:59

Hi,
pls let me know how to create a bitmap dynamically..and need to draw a rect on the bitmap...

Re: Bitmap

Rajesh R Subramanian13-Dec-09 22:06

Rajesh R Subramanian

13-Dec-09 22:06

What are you using? MFC? WTL? Win32?

kumar sanghvi wrote:
need to draw a rect on the bitmap...

Please search the site: Drawing lines, shapes, or text on bitmaps[^]

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