Help with multiple classes - C / C++ / MFC Discussion Boards

Re: newbie : why doesn't this work? plz plz plz

davun8-Apr-02 8:34

8-Apr-02 8:34

Thanks Ernest,

but can I ask, how would one
convert a string to long double?

Would I need to use atof(), then
use a static cast to ld? I would
think there is a direct method.

Thanks for your help.

David

Re: newbie : why doesn't this work? plz plz plz

lucy8-Apr-02 8:46

lucy

8-Apr-02 8:46

according to MS document, long double is equal to double. and atof() will convert a string to double. I think this is what you want for the assignment?

Re: newbie : why doesn't this work? plz plz plz

8-Apr-02 8:47

atof function does return a double value.

Try this ...

#include <stdlib.h>
#include <stdio.h>
#include <isostream.h>

using namespace std;

int main()
{
char str1[] = "123.21";

double d = atof(str1);

cout << d;

return 0;
}

Re: newbie : why doesn't this work? plz plz plz

davun8-Apr-02 9:24

davun

8-Apr-02 9:24

thanks all. Very much appreciated.

ScrollWindowEx Problem!

G.Richard8-Apr-02 5:43

G.Richard

8-Apr-02 5:43

does anyone knows how to use ScrollWindowEx?

c++ : my dream

Re: ScrollWindowEx Problem!

alex.barylski8-Apr-02 7:22

alex.barylski

8-Apr-02 7:22

Nope..no one uses ScrollWindowEx anymore... Poke tongue | ;-P

I'm afraid your going to have to be more specific than that...

Cheers

"An expert is someone who has made all the mistakes in his or her field" - Niels Bohr

Re: ScrollWindowEx Problem!

G.Richard9-Apr-02 3:36

G.Richard

9-Apr-02 3:36

I want to use the ScrollWindowEx to animate window, when scrolling.
i mean I can't use ScrollwindowEx do the same thing that scrollwindow do, if i change the last parameter to SW_SMOOTHSCROLL. it can't update the region scrolled.why not have a try? you can test the following code inyou application.

...
CRect rcClient;
GetClientRect(&rcClient);
ScrollwindowEx(100,0, &rcClient, &rcClient, NULL,NULL, SW_SMOOTHSCROLL);
...

c++ : my dream

Help with multiple classes

Xds8-Apr-02 5:32

Xds

8-Apr-02 5:32

Hi all,

This is my first post; I'm new to C++ so go easy on me.
I have two classes; and their functions include code that refer to the other:
i.e: Class X has code that uses a variable/function from Class Y and vice-versa. The classes are completely different, so it would not help to derive one off the other.

In Header.h:

------------------------------------------------------------
class X {
public:
	int  myint;
	void doit(void);
};

void X::doit(void) {
	printf("CY.myint = %i", CY.myint); // Print Class Y's myint
}


class Y {
public:
	int  myint;
	void doit(void);
};

void Y::doit(void) {
	printf("CX.myint = %i", CX.myint); // Print Class X's myint
}
------------------------------------------------------------

In Main.CPP:

------------------------------------------------------------
#include  "stdio.h"
#include "Header.h"

int main(void) {

	class X CX;
	class Y CY;

	CX.myint = 100;
	CY.myint = 200;
	CX.doit();
	CY.doit();

	return 1;

}
------------------------------------------------------------

How can I get these classes to work together?
I can't put an 'extern class Y' before the 'class X' declaration, so how can I let the compiler know that the other class exists and will be declared?

Thanks!

Mike

Re: Help with multiple classes

Rickard Andersson²⁰8-Apr-02 5:39

Rickard Andersson²⁰

8-Apr-02 5:39

Xds wrote:
int main(void)
{
class X CX;
class Y CY;

CX.myint = 100;
CY.myint = 200;

CX.doit();
CY.doit();

return 1;
}

I'm not sure about this but isn't it "wrong" to write 'class X CX'?
Isn't 'X CX' the right way!?

I can be wrong!!!!!!

------------------------------------
Rickard Andersson, Suza Computing
ICQ#: 50302279
I'm from the winter country SWEDEN!

------------------------------------

Re: Help with multiple classes

Xds8-Apr-02 5:49

Xds

8-Apr-02 5:49

Pretty sure it works either way, but in any case, that's not the problem.
Thanks!

Mike

Re: Help with multiple classes

Roger Allen8-Apr-02 6:09

Roger Allen

8-Apr-02 6:09

You need to use a forward declaration of the class.

class Y ; // forward class declaration

class X
{
 void DoIt(Y& y) ; // pass in a reference to a Y object
} ;

class Y
{
} ;

You also cannot print out the content of CY in CX unless you pass a reference / pointer / copy of the object you want to print in as a parameter. The CX in main does not know anything about the CY:

#include  "stdio.h"
#include "Header.h"
int main(void) 
{
	X CX;
	Y CY;
	CX.myint = 100;
	CY.myint = 200;
	CX.doit(CY); // see class declaration above
	CY.doit();
	return 1;
}

Roger Allen
Sonork 100.10016

If I'm not breathing, I'm either dead or holding my breath.
A fool jabbers, while a wise man listens. But is he so wise to listen to the fool?

Re: Help with multiple classes

Le centriste8-Apr-02 7:34

Le centriste

8-Apr-02 7:34

That code wont't compile because in your doit methods you reference hard-coded instances.
Michel

If I am wrong or said something stupid, I apologize in advance Wink | ;)

Need a control to show .gif files

Hans Ruck8-Apr-02 5:26

Hans Ruck

8-Apr-02 5:26

Do you know an activex control able to show .gif files?

rechi

Re: Need a control to show .gif files

C^hris L^osinger8-Apr-02 5:31

C^hris L^osinger

8-Apr-02 5:31

first, you need a GIF/LZW license. see www.unisys.com.

-c

   "What the hell are you getting so upset about? I thought you didn't believe in God".
   "I don't," she sobbed, bursting violently into tears, "but the God I don't believe in is a good God, a just God, a merciful God. He's not the mean and stupid God you make Him out to be".
   -- Joseph Heller

Smaller Animals Software, Inc.

Re: Need a control to show .gif files

Carlos Antollini8-Apr-02 5:39

Carlos Antollini

8-Apr-02 5:39

Use image.ocx...

Regards...

A couple of month agou in MSDN magazine, Paul Dilascia wrote a class for display those type of files....

Regards

Carlos Antollini.
Sonork ID 100.10529 cantollini

Re: Need a control to show .gif files

Rickard Andersson²⁰8-Apr-02 5:41

Rickard Andersson²⁰

8-Apr-02 5:41

I'm pretty sure there is an article here on CP about that!

------------------------------------
Rickard Andersson, Suza Computing
ICQ#: 50302279
I'm from the winter country SWEDEN!

------------------------------------

Re: Need a control to show .gif files

Hans Ruck8-Apr-02 8:27

Hans Ruck

8-Apr-02 8:27

Thank you all, the problem is now solved!
Thanks1

rechi

Using Arabic Character in the MFC

Mesut8-Apr-02 5:23

Mesut

8-Apr-02 5:23

hi,
I want the arabic character writing in the Edit Text and Static Text in the English Windows (No Arabic Windows) . Arabic fonts is best writing but it is wrong connect the arabic character.. (in the MFC od Embedded VC++)..
I'm not good speak englih.. Sorry all!
Please help me.

best regads..

Mesut
mgencer99@hotmail.com

MFC

Re: Using Arabic Character in the MFC

Carlos Antollini8-Apr-02 5:43

Carlos Antollini

8-Apr-02 5:43

You need to use Unicode Strings, and need to work in a PC with that language. Never but never save the project in a pc, with another idiom.
I worked in a multy language project, And I nedded to save same parts of the project in OS that supports that languajes, like Arabic, Hebrew and Russian...

Carlos Antollini.
Sonork ID 100.10529 cantollini

Re: Using Arabic Character in the MFC

Carlos Antollini8-Apr-02 5:44

Carlos Antollini

8-Apr-02 5:44

You need to set the RTL proprti in the Edit and in the static controls, the same for the combo boxes

Carlos Antollini.
Sonork ID 100.10529 cantollini

help

8-Apr-02 3:41

Dose anybody know where I can find demonstration packages programmed in Visual c++, which show you the encryption of eg transposition cipher. I can find alot of help in Java but sadly none in Visual c++

Any suggestions? urls? Or people I can e-mail?

thanks

Problems with accessing a control from another class

James P8-Apr-02 3:22

James P

8-Apr-02 3:22

I am well and truely stumped. I have created a progress bar within a formview and I am trying to access it via a totally different class and getting all sort of errors.

Here is the code: -
percentage=int(((float)i/(float)(mrecords*4))*100.0);
str.Format("Mailsort is %d%% complete (Coding - %s)", percentage, currentmailsortfile);
m_progress.SetWindowText(str);
m_progress.SetPos(percentage);

and the progress control is created in the IYIView.h header file as follows: -

//{{AFX_DATA(CIYIView) enum { IDD = IDD_IYI_FORM };
CTextProgressCtrl m_progress;
//}}AFX_DATA

I am trying to access the view header file (IYIView.h) in order to create an instance of the class and access the progress control (m_progress) but I am getting the following errors on compliation but don't know how to get round it without effecting the rest of the program.

d:\my projects\iyi\iyiview.h(23) : error C2065: 'IDD_IYI_FORM' : undeclared identifierd:\my projects\iyi\iyiview.h(23) : error C2057: expected constant expression
d:\my projects\iyi\iyiview.h(115) : error C2143: syntax error : missing ';' before '*'
d:\my projects\iyi\iyiview.h(115) : error C2501: 'CIYIDoc' : missing storage-class or type specifiers
d:\my projects\iyi\iyiview.h(115) : error C2501: 'GetDocument' : missing storage-class or type specifiers

MSDN is no help, so do you have any ideas?!?

Re: Problems with accessing a control from another class

Mazdak8-Apr-02 4:06

Mazdak

8-Apr-02 4:06

Check this.

Mazy

"The path you tread is narrow and the drop is shear and very high,
The ravens all are watching from a vantage point near by,
Apprehension creeping like a choo-train uo your spine,
Will the tightrope reach the end;will the final cuplet rhyme?"Cymbaline-Pink Floyd

Re: Problems with accessing a control from another class

James P8-Apr-02 5:31

James P

8-Apr-02 5:31

I don't need to access the whole view but simply the progress bar to update from a different class. Is it really necessary to do all of this code just to pass a value to a control?

Re: Problems with accessing a control from another class

Mazdak8-Apr-02 6:02

Mazdak

8-Apr-02 6:02

James P wrote:
Is it really necessary to do all of this code just to pass a value to a control?

If you wanna use your view you have to do something like that.There are another way exist but I didn't test.Read the messages at the bottom of that article,they are easier. Smile | :)

Mazy

"The path you tread is narrow and the drop is shear and very high,
The ravens all are watching from a vantage point near by,
Apprehension creeping like a choo-train uo your spine,
Will the tightrope reach the end;will the final cuplet rhyme?"Cymbaline-Pink Floyd

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