C / C++ / MFC

Re: Send a program to another PC & execute it there .....

4-Apr-08 11:20

or virus

led mike

Eytukan5-Apr-08 7:52

Eytukan

5-Apr-08 7:52

or trojan.

OK,. what country just started work for the day ? The ASP.NET forum is flooded with retarded questions. -Christian Graus

Best wishes to Rexx[^]

Re: Send a program to another PC & execute it there .....

Hamid_RT7-Apr-08 20:54

Hamid_RT

7-Apr-08 20:54

See here[^] and here[^].

CStatic-Derived class: painting background

42884-Apr-08 6:53

4-Apr-08 6:53

Hi all,
I need to paint the background of a CStatic control created dynamically this way:

CUnknownCtrl* pUnknown;
pUnknown = new CUnknownCtrl;
pUnknown->Create("Text", SS_CENTER | WS_CHILD | WS_VISIBLE | WS_GROUP, CRect(11,35,360,526), this, 0x31);

Notice that CUnknownCtrl is a CStatic-derived mfc class.

I can't figure out how to set background color of the label created with this code, someone can help me?
Calling OnCtlColor inside CUnknownCtrl won't even be executed and OnPaint fails. Some idea?

Thanks for advance

---

Nitheesh George4-Apr-08 7:06

Nitheesh George

4-Apr-08 7:06

Hi,

Simply handle the WM_CTLCOLORSTATIC message in your class. The WM_CTLCOLORSTATIC is send to a static control when its background color need to drawn.

thanks.

Nitheesh

Gary R. Wheeler6-Apr-08 1:45

Gary R. Wheeler

6-Apr-08 1:45

WM_CTLCOLORSTATIC is sent to the parent window of the static control, not the static control itself.

Software Zen: delete this;
Fold With Us![^]

led mike4-Apr-08 7:09

4-Apr-08 7:09

4288 wrote:
and OnPaint fails

What does that mean?

led mike

42884-Apr-08 7:28

4-Apr-08 7:28

I used OnCtlColor handler, but because my label was created with a CStatic-derived class, the code provided into CMyClass::OnCtlColor won't be executed!

OnPaint seemed me a good solution but if I insert the OnPaint handler with Visual Studio, the control won't even show

---

led mike4-Apr-08 7:59

4-Apr-08 7:59

4288 wrote:
but if I insert the OnPaint handler with Visual Studio, the control won't even show

Did you subclass the control?[^]

led mike

42884-Apr-08 8:33

4-Apr-08 8:33

I thought I subclassed it, but my subclassing seems not to work.
Have you got please a link that show how to perform a subclassing with a dynamical control created like mine?

---

Hamid_RT7-Apr-08 20:52

Hamid_RT

7-Apr-08 20:52

See here[^].

42888-Apr-08 7:23

8-Apr-08 7:23

Problem solved, thanks!

---

A very basic question about ODBC

Hamid_RT8-Apr-08 8:00

Hamid_RT

8-Apr-08 8:00

Very good. Big Grin | :-D

Joseph Marzbani4-Apr-08 5:34

Joseph Marzbani

4-Apr-08 5:34

Hi every body!
From where can I get some information about "Connection Strings" used to connect to MS Access Database. For example I don't know what "MaxBufferSize" means and so on...

Don't laught at me! I know what U R thinking about... Laugh | :laugh:

Re: A very basic question about ODBC

David Crow4-Apr-08 6:04

David Crow

4-Apr-08 6:04

Usef Marzbani wrote:
For example I don't know what "MaxBufferSize" means and so on...

It refers to the amount of RAM Access sets aside for its use as an internal storage space. The larger the storage space, the higher are the odds that the data necessary for a request can be found in RAM and will not require physical disk access.

"Love people and use things, not love things and use people." - Unknown

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Re: A very basic question about ODBC

Mark Salsbery4-Apr-08 7:18

Mark Salsbery

4-Apr-08 7:18

connectionstrings.com[^]

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

Chump Is Stumped By VARIANT Problem

Eurosid4-Apr-08 4:34

4-Apr-08 4:34

So I have this COM object that's packing up an array floats for me.

Here's the loop where the VARIANT* array is getting stuffed:

for (i = 0; i < cElements; i++)
{
     VariantInit(&vDataValues[i]);
     V_VT(&vDataValues[i]) = VT_R4;

     //Works ok UNLESS float_data[i] == 0.0;
     V_R4(&vDataValues[i]) = float_data[i];

     if (!V_R4(&vDataValues[i]))
     {
          *pErrorCode = 1;
          m_strMessage.Format("V_R4 failed!");
          hr = E_FAIL;
          goto Error;
     }
}

The VT_R4() operation works unless the element in float_data
happens to be 0.0. When that happens, VT_R4 fails.

I know it fails only with 0.0, because I tried this:
if( float_data[i] != 0.0 )
     V_R4(&vDataValues[i]) = float_data[i];
else
     V_R4(&vDataValues[i]) = float_data[i] + 0.1;

Then, it never fails.

I can't figure out why.

led mike4-Apr-08 5:04

4-Apr-08 5:04

Well I have no idea what your float_data is or if it has been properly initialized but this works without error

    VARIANT DataValues[4];
    V_R4( &DataValues[0]) = 0.0;

led mike

Eurosid4-Apr-08 5:21

4-Apr-08 5:21

I'm new to using COM, so maybe I'm missing something obvious here.

The data I can verify is OK.

led mike wrote:
VARIANT DataValues[4];
V_R4( &DataValues[0]) = 0.0;

Those lines work for me, too.

The examples I'm looking show that you verify it's OK by doing this sort of thing:

if (!V_R4(&vDataValues[i]))
{
//Do some error stuff
}

And !V_R4(&vDataValues[i]) evaluates to false if the data is 0.0.

Why is that? Confused | :confused:

If I comment out that error check, everything seems to work fine. Is it not needed?

led mike4-Apr-08 5:32

4-Apr-08 5:32

Eurosid wrote:
The examples I'm looking show that you verify it's OK by doing this sort of thing:

I don't think that's correct. Where are you getting these examples?

V_R4 is just a macro that evaluates to the specified VARIANT member during pre-compile. It does not return an status indication value.

led mike

Eurosid4-Apr-08 5:49

4-Apr-08 5:49

You are exactly correct. I misunderstood what I was looking at.

The example was for packing up a BSTR, so they did such a check
to make sure the pointer wasn't NULL.

Doing the same thing on a float isn't needed, but will look OK unless the value happens to be 0, which will look like FALSE.

I told you I was a Chump!

Thank you for help!

Iain Clarke, Warrior Programmer

Iain Clarke, Warrior Programmer4-Apr-08 5:43

4-Apr-08 5:43

I'm slightly curious what you mean by "fails". Do you put the variant in a watch window, and see wrong numbers? From your later post, I think you think that V_R4 is a function which passes success / failure.

Looking in OLEAUTO.H,

#define V_UNION(X, Y)   ((X)->Y)
#define V_VT(X)         ((X)->vt)
#define V_R4(X)          V_UNION(X, fltVal)

So...

VARIANT var;
VariantInit (&var);
V_VT(&var) = VT_R4;
V_R4(&var) = 0.0;

becomes

V_UNION(&var,ftlVal) = 0.0;

becomes

(&var)->ftlVal = 0.0;

which looks fine to me.

BUT:

You are using this in an if statement.

Imagine the following:

if (1)
{
   //  pretty guaranteed to get here
} else {
   // not likely...
}

and

if (a=0)
{
   //  pretty unlikely to get here
} else {
   // 
}

The second if evaluates to 0, which will fail the if.

Cutting to the chase:

V_R4(&blah) = a number

evaluates to whatever the number is - and 0 is FALSE.

Here endeth the lesson.

Iain.

Iain Clarke appears because ^CPallini still cares.

Eurosid4-Apr-08 5:51