C / C++ / MFC Discussion Boards

How can set text of button at runtime?

Le@rner2-Jul-08 23:47

Le@rner

2-Jul-08 23:47

Hi all,

Can anyone tell me how can i set the text of any button at runtime.

Thanks in advance.

IN A DAY, WHEN YOU DON'T COME ACROSS ANY PROBLEMS - YOU CAN BE SURE THAT YOU ARE TRAVELLING IN A WRONG PATH

Re: How can set text of button at runtime?

Rajesh R Subramanian2-Jul-08 23:53

Rajesh R Subramanian

2-Jul-08 23:53

SetWindowText()[^] ?

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Visual C++ MVP

Re: How can set text of button at runtime?

_AnsHUMAN_ 2-Jul-08 23:54

_AnsHUMAN_

2-Jul-08 23:54

buttonObj.SetWindowText(/*parameter*/)

Somethings seem HARD to do, until we know how to do them.
Wink | ;-)

_AnShUmAn_

Re: How can set text of button at runtime?

Paresh Chitte2-Jul-08 23:54

Paresh Chitte

2-Jul-08 23:54

Use SetWindowText API.

Regards,
Paresh.

Re: How can set text of button at runtime?

Hamid_RT3-Jul-08 1:38

Hamid_RT

3-Jul-08 1:38

Or you can use of SetDlgItemText or WM_SETTEXT.

UAC in Vista

subramanyeswari2-Jul-08 23:35

subramanyeswari

2-Jul-08 23:35

Hi,

I read that if Vista sees an external manifest file if will enable prompt. That's why we have to embed manifest file in the exe to enable application for UAC. Is it right? If any one knows that link can u send me that link.
I am trying to find that link for couple of hours but i am not able to find it now.

Thanks

Re: UAC in Vista

Rajesh R Subramanian2-Jul-08 23:55

Rajesh R Subramanian

2-Jul-08 23:55

Which link? Confused | :confused:

If you have a query, may be someone can answer you, not that you have to go back to that link.

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Visual C++ MVP

Re: UAC in Vista

subramanyeswari3-Jul-08 2:17

subramanyeswari

3-Jul-08 2:17

My question is why should I embed manifest file in the exe to run in Vista.

Regards

Re: UAC in Vista

Nibu babu thomas3-Jul-08 3:35

Nibu babu thomas

3-Jul-08 3:35

subramanyeswari wrote:
My question is why should I embed manifest file in the exe to run in Vista.

Can you check this[^] video on channel 9.

Google search on this topic[^]

Nibu babu thomas
Microsoft MVP for VC++

Code must be written to be read, not by the compiler, but by another human being.

Programming Blog: http://nibuthomas.wordpress.com

How to Clear IE history under a limited account of VISTA

moye25012-Jul-08 22:26

moye2501

2-Jul-08 22:26

The code works under XP, both administrator or limited account.
But when I run it under Vista, it works under a administrator account, but doesn't work under limited account.
Sometimes, the history is cleared at first, but it appears again when I restart IE.

The code is shown as follow:

USES_CONVERSION;
CoInitialize(NULL);

TCHAR szSpecialFolderPath[MAX_PATH];
::SHGetSpecialFolderPath(::GetDesktopWindow(), szSpecialFolderPath, CSIDL_HISTORY, FALSE);

IUrlHistoryStg2* pUrlHistoryStg2 = NULL;
HRESULT hr = CoCreateInstance(CLSID_CUrlHistory, NULL, CLSCTX_ALL, IID_IUrlHistoryStg2, (void**)&pUrlHistoryStg2);
if(SUCCEEDED(hr))
{
    hr = pUrlHistoryStg2->ClearHistory();
    pUrlHistoryStg2->Release();
    CoUninitialize();
    return TRUE;
}
else
{
    CoUninitialize();
    return FALSE;
}

Thanks a lot!

The stack conventions are different in AfxBeginThread and CreateThread

followait2-Jul-08 21:37

followait

2-Jul-08 21:37

With AfxBeginThread, it is __cdecl,
with CreateThread, it is __stdcall.

Is there an safe API wait to create a thread in MFC?
CreateThread?
I'd like to the easier one, if there is.

Re: The stack conventions are different in AfxBeginThread and CreateThread

Iain Clarke, Warrior Programmer2-Jul-08 22:03

Iain Clarke, Warrior Programmer

2-Jul-08 22:03

followait wrote:

Is there an safe API wait to create a thread in MFC?

Err, AfxBeginThread is an MFC function...

Not sure what else you're after.

Iain.

Plz sir... ^CPallini ^CPallini abuz drugz, plz plz help urgent.

Re: The stack conventions are different in AfxBeginThread and CreateThread

Saurabh.Garg2-Jul-08 22:12

Saurabh.Garg

2-Jul-08 22:12

followait wrote:
I'd like to the easier one, if there is.

Nothing is easy in multi-threading.

-Saurabh

Re: The stack conventions are different in AfxBeginThread and CreateThread

CPallini2-Jul-08 22:22

CPallini

2-Jul-08 22:22

Philosophical mood this afternoon?
Big Grin | :-D

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Re: The stack conventions are different in AfxBeginThread and CreateThread

Saurabh.Garg2-Jul-08 22:27

Saurabh.Garg

2-Jul-08 22:27

Yes!! Trying to finish this boring piece of code before I call it day Sniff | :^)

But I guess that statement is pretty much always true for any non-trivial applications Poke tongue | ;-P

-Saurabh

Re: The stack conventions are different in AfxBeginThread and CreateThread

Roger Stoltz2-Jul-08 22:23

Roger Stoltz

2-Jul-08 22:23

When you're using MFC you have to use AfxBeginThread due to internal workings of the framework.

For more info:
http://www.flounder.com/badprogram.htm#beginthread[^]

The best starting point for multithreading can be found here[^].

"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown

How to hide a public function inherit from base class

Dracula Wang2-Jul-08 21:27

Dracula Wang

2-Jul-08 21:27

I have 2 classes, B inherit from A, but actually A have a function: fun should not present in B, so I code as blow,

class A{
public:
    virtual void fun(){cout << "a" << endl; };
};

class B : public A{
    virtual void fun(){};
};

But this take no effect, I can call the fun in class b,

int main()
{
    A a;
    B b;
    A *pa = new B;

    a.fun();
    b.A::fun();
    pa->fun();
}

the output is

a
a

How to decline the function call?
Thanks.

Re: How to hide a public function inherit from base class

CPallini2-Jul-08 21:36

CPallini

2-Jul-08 21:36

What is your point?
pa->fun() doesn't fit your needs?

Re: How to hide a public function inherit from base class

Dracula Wang2-Jul-08 21:50

Dracula Wang

2-Jul-08 21:50

yes,

the A::fun() is bad for the B, will case error,
so i want let A::fun to be public, but to B the fun must cannot be call

Re: How to hide a public function inherit from base class

CPallini2-Jul-08 21:56

CPallini

2-Jul-08 21:56

What about
(1) Writing A class without fun function.
(2) Writing a (say) AA class that inherits from A and provides fun function.
(3) Writing a B class that inherits from A class and therefore is not able to call fun function?

Of course A class consumers should become AA class ones.

Smile | :)

Re: How to hide a public function inherit from base class

Dracula Wang2-Jul-08 22:05

Dracula Wang

2-Jul-08 22:05

yeah, that's the better way to do,
but in this project others may dislike this implement, they didn't want their code update, @_@.

Thanks for all your help.

Re: How to hide a public function inherit from base class

BadKarma3-Jul-08 1:21

BadKarma

3-Jul-08 1:21

Hi,

I don't understand what you don't want to happen for the B class.

do you want to hide the functionaly from a b object or the declaration;

like this:

int main()
{
 A a;
 B b;

 a.fun();  //  outputs "a"
 b.fun();  //  compiles but doens't do something
 // or
 b.fun();  //  doens't compile

 A* p = &b;
 p->fun(); //  compiles but doens't do something

 b.A::fun();  // compiles but doens't do something
 
}

Maybe you could use the Facade pattern to hide the unwanted A functionaly.

Learn from the mistakes of others, you may not live long enough to make them all yourself.

Floating point assembler code [modified]

Tomerland2-Jul-08 20:56

Tomerland

2-Jul-08 20:56

Dear gurus,

I detected a runtime-bottleneck in my code at the following line

pY[j] = d1 * pY[j] + d2 * pX[j];

.

All variables are floating point. This line is excecuted millions of times.
Now I think about improving runtime by using inline-assembler.

Can somebody give me a hint how to start in the best way (e.g. using a library)

(by the way: I'm not a beginner at assembler-coding)

Kind regards

modified on Thursday, July 3, 2008 5:16 AM

Re: Floating point assembler code

Roger Stoltz3-Jul-08 2:09

Roger Stoltz

3-Jul-08 2:09

Tomerland wrote:
All variables are floating point. This line is excecuted millions of times.
Now I think about improving runtime by using inline-assembler.

I would recommend you to not use inline-asm for various reasons, but the primary reason is "there must be a better way".

A few things to reflect upon:

1. Floating point instructions are slow.
Does it have to be floating points or would integer values suffice?

2. Updating an array of floating points is rarely a "bottleneck" from a data administration point of view. You rarely take time critical actions based upon floating point calculation with e.g. 15-bit exponent and a 64-bit mantissa which is what you have when using long double.
If you're doing this from your GUI thread it will become unresponsive and the user will experience the UI as hung, but that's another problem.
Is it not possible to calculate the new values of the array in a worker thread and post a message to the GUI thread when the calculation has finished?

3. How about using integers that are multiplied by e.g. 100?
When you calculate with the values you have two "decimals", but when you present the value to the user, or store it, you can convert to a floating point value.
I used this technique in an embedded system that had no support for floating point values, but I multiplied with 16 instead which was a good enough approximation.

"It's supposed to be hard, otherwise anybody could do it!" - selfquote
"High speed never compensates for wrong direction!" - unknown

Re: Floating point assembler code

Alan Balkany3-Jul-08 4:57

Alan Balkany

3-Jul-08 4:57

A few ideas:

1. Since the line is executed millions of times, you may be able to speed it up with loop unrolling http://en.wikipedia.org/wiki/Loop_unrolling[^].

2. Every time you do pY[j], it requires a multiplication and an addition. If you're processing the array sequentially, it would be faster to start with a pointer to pY[0], then increment it to get the next array element.

If you show some more surrounding code, we may be able to see some other optimizations.

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