GUI Calculator in C language

Its becoz i come across this visopsys OS. then i want to use this platform and do a GUI calculator.

Hope u can advice me.

I looked around, and could find nothing to indicate how to write anything at all for visopsys. I think your best bet is to download it, find the source for a few appplications, and use that as a template for your own apps.

Yes, it is possible.  Yes, it is difficult.

Can you help find the source for me and how i can use it. I not quite sure how can i start.....

The source for visopsys is here:

http://visopsys.org/files/visopsys/visopsys-0.63-src.zip

The sketchy window system documentation is here:

http://visopsys.org/developers/window_library.html

This is not sufficient to write an application that works.  You will have to study the source code to figure how to code an application.

It will be easier to develop a calculator with a GUI for a more established, better documented platform.

Can guild me how to start. i am quite lost

Is this a simple calculator like what you would buy at dollar store or a scientific calculator? What operators will it support? Will it support variables?

Aron

How about starting very very simple?

Use the GUI tool of you choice. then add one output media. Add a few button representing the numbers, add one command  button like + and then see that this stuff works. Over time you simply can add more and more stuff and maybe you can look into sources of existing "calculators".

You can get some calculator (Windows GUI) at:
http://www.johnfindlay.plus.com/lcc-win32/sci_math/Numero.zip it's just about 17K.. So not that big really

Regards
Friedrich

Hi AronRubin , i would be just a simple GUI cal with simple operation like add,minus,mutiple and divide. My problem is the window API of visopsys OS.

Hope you u can advice

Visopsys seems to be an own operating system. If you do not have it, GUI libraries targeting this platform are definitly not what you can use. With high likliness you are either on Linux or Windows the for Windows you should visit the page I mentioned because this is calculator is written for Windows.

Regards
Friedrich

How can i use the Numero.zip and change the window Gui to least visopsys Gui first?

If it can be run in visopsy then will try to add in button etc for the caluculation.

I was wondering visopsys uses it own windows Api. Does this works?

i think no right?

yes I bothered to read the source.

Yes u mean visopsys can works?

it uses the visopsys API. I cannot claim that it will run because I could not compile, debug, or test.

Ic
Thanks

I will try to figure out how to complie in visipsys.

I cant seem to figure out how i can complie the calc.c  in visopsys which AronRubin  posted.

Can someone teach me how to compile, debug and test.

i try to complie and get this error

calc.c: In function `eventHandler':
calc.c:19: warning: unused parameter `event'  
calc.c: In function `main':
calc.c:79: warning: unused parameter `argc'
calc.c:79: warning: unused parameter `argv'


line 19 -> static void eventHandler( objectKey obj, windowEvent *event )
line 79 -> int main( int argc, char *argv[] )

Those are not errors, they are warnings.

babypink,
  I imagine some people could. They have whole courses on this stuff ;) What problems are you having that need improvement?

Hi AronRubin

then how can i run it?

persumably by double clicking on the executable produced. If you did not give it a name, traditionally it would be called a.out

In i am using Bloodshed Dev-C++

Are u refering to linux platform?

Hi AronRubin,

I try in Fedora core 5 using GCC and windowa using Bloodshed Dev-C++.

Cant get it fix

Can u tell me ur detail step in compiling. like what platform, what software etc?....

Thanks

I did not compile for visopsys because I do not run that software. If you were looking for a easy gui api on Linux you could try http://otk.sf.net or if you are looking for a main stream gui api you could try gtk+.

for otk
windowNewTextLabel above becomes OtkMakeTextLabel
windowNewButton above becomes OtkMakeButton
etc.

for gtk+
windowNewTextLabel becomes gtk_label_new and gtk_container_add
windowNewButton becomes gtk_button_new_with_label and gtk_container_add
etc.

Hi AronRubin ,

sorry to trouble u
Can u try to compile visopsys.
And tell me what the step to do it
I seem cant to get in work...

nope, I have negative time for such things.

anyone out there can help?

i try to compile and get this warning...

I think need to solve this warning in order to to compile properly in visopsys

Experts pls help to solve

Thank in advance

calc.c: In function `eventHandler':
calc.c:19: warning: unused parameter `event'  
calc.c: In function `main':
calc.c:79: warning: unused parameter `argc'
calc.c:79: warning: unused parameter `argv'


line 19 -> static void eventHandler( objectKey obj, windowEvent *event )
line 79 -> int main( int argc, char *argv[] )

is there any kind soul out there?

MS Style solution:
#define UNREFERENCED_PARAMETER(P) {(P)=(P);}

then later:
UNREFERENCED_PARAMETER(event);
etc.

i am using fedora 5..............

Hi i manage to get it into Visopsys
However some problem with the program. pls refer to the image link
http://img131.imageshack.us/my.php?image=calczf6.jpg

below is the source code...
===================================

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/api.h>
#include <sys/window.h>

objectKey answerLabel = NULL;
objectKey btnCE = NULL;
objectKey btnC = NULL;
objectKey btnBS = NULL;
objectKey btneq = NULL;
objectKey btnnum[10] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL };
objectKey btnadd = NULL;
objectKey btnsub = NULL;
objectKey btnmul = NULL;
objectKey btndiv = NULL;
objectKey btnsgn = NULL;
objectKey btndot = NULL;



static void eventHandler( objectKey obj, windowEvent *event ) {
      
      static objectKey window = NULL;
 
  window =0;
  event =0;
 
 
 
  static float value = 0, lastval = 0;
  static char answer[128];
  static int operands = 0;
  static int operation;
  static int i;
  /*static int dot = 0;*/

  if(obj == btnCE ) {
    value = 0;
    lastval = 0;
    operands = 0;
  } else if( obj == btnC ) {
    if( operands > 0 )
      operands--;
    if( operands > 1 )
      value = lastval;
  } else if( obj == btnBS ) {
  } else if( obj == btneq  || obj == btnadd || obj == btnsub ||
          obj == btnmul || obj == btndiv ) {
    if( operands > 1 ) {
      switch( operation ) {
      case 0: lastval = value = lastval + value; break;
      case 1: lastval = value = lastval - value; break;
      case 2: lastval = value = lastval * value; break;
      case 3: lastval = value = lastval / value; break;
      }
      operands = 1;
      if( obj != btneq ) {
      }
    }
    if( operands > 0 ) {
      if( obj == btnadd ) {
     lastval = value;
     operands++;
     operation = 0;
      } else if( obj == btnsub ) {
     lastval = value;
     operands++;
     operation = 1;
      } else if( obj == btnmul ) {
     lastval = value;
     operands++;
     operation = 2;
      } else if( obj == btndiv ) {
     lastval = value;
     operands++;
     operation = 3;
      }
    }
  } else {
    for( i = 0; i < 10; i++ )
      if( obj == btnnum[i] )
     value = value*10.0 + (float)i;
  }

  sprintf( answer, "%g", value );
  windowComponentSetData( answerLabel, answer, strlen( answer ) );
}

void main(int argc, char *argv[]) {
 
 
argc = 0;
argv =0;      
 
  /*int status = 0;*/
  componentParameters params;
  static objectKey top = NULL;

  /*int count;*/

  // Create a new window
  top = windowNew(multitaskerGetCurrentProcessId(), "Calc");
 
   

  bzero(&params, sizeof(componentParameters));
  params.gridWidth = 4;
  params.gridHeight = 1;
  params.padLeft = 5;
  params.padRight = 5;
  params.padTop = 5;
  params.padBottom = 5;
  params.orientationX = orient_left;
  params.orientationY = orient_middle;
  /*params.flags |= WINDOW_COMPFLAG_FIXEDWIDTH;*/
  answerLabel = windowNewTextLabel( top, "0", &params );

  params.gridWidth = 1;
  params.gridY = 1;
  params.orientationX = orient_center;

  btnCE = windowNewButton( top, "CE", NULL, &params );
  params.gridX++;
  btnC = windowNewButton( top, "C", NULL, &params );
  params.gridX++;
  btnBS = windowNewButton( top, "BS", NULL, &params );
  params.gridX++;
  btneq = windowNewButton( top, "=", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[7] = windowNewButton( top, "7", NULL, &params );
  params.gridX++;
  btnnum[6] = windowNewButton( top, "8", NULL, &params );
  params.gridX++;
  btnnum[5] = windowNewButton( top, "9", NULL, &params );
  params.gridX++;
  btndiv = windowNewButton( top, "/", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[4] = windowNewButton( top, "4", NULL, &params );
  params.gridX++;
  btnnum[5] = windowNewButton( top, "5", NULL, &params );
  params.gridX++;
  btnnum[6] = windowNewButton( top, "6", NULL, &params );
  params.gridX++;
  btnmul = windowNewButton( top, "*", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[1] = windowNewButton( top, "1", NULL, &params );
  params.gridX++;
  btnnum[2] = windowNewButton( top, "2", NULL, &params );
  params.gridX++;
  btnnum[3] = windowNewButton( top, "3", NULL, &params );
  params.gridX++;
  btnsub = windowNewButton( top, "-", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[0] = windowNewButton( top, "0", NULL, &params );
  params.gridX++;
  btnsgn = windowNewButton( top, "-+", NULL, &params );
  params.gridX++;
  btndot = windowNewButton( top, ".", NULL, &params );
  params.gridX++;
  btnadd = windowNewButton( top, "+", NULL, &params );

  windowRegisterEventHandler( top, &eventHandler);

  windowGuiRun();
}





 
 

AronRubin once again will need your help...

Thanks in advance

Hi AronRubin

i have manage to solve the above program...

however when i click the number... the screen will not change the value.

meaning whatever i click the value remain at "0"

is it this part of code have the problem?

  printf( answer, "%c", value );
  windowComponentSetData( answerLabel, answer, strlen( answer ) );

Somehow it does not show anything in the answerLabel

You altered the sprintf line, was that intentional?

you could try two things
1. change the above line to:
windowComponentSetData( answerLabel, answer, strlen( answer ) + 1 );
2. you could try forcing a redraw after the value change:
windowComponentDraw( answerLabel );

It still cant work. I copy n paste all the code here. Please help me to solve the problem. Thanks

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/api.h>
#include <sys/window.h>

static objectKey answerLabel = NULL;
static objectKey btnCE = NULL;
static objectKey btnC = NULL;
static objectKey btnBS = NULL;
static objectKey btneq = NULL;
static objectKey btnnum[10] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL };
static objectKey btnadd = NULL;
static objectKey btnsub = NULL;
static objectKey btnmul = NULL;
static objectKey btndiv = NULL;
static objectKey btnsgn = NULL;
static objectKey btndot = NULL;
static objectKey top = NULL;

static void eventHandler( objectKey obj, windowEvent *event ) {
 
  static float value = 0, lastval = 0;
  static char answer[128];
  static int operands = 0;
  static int operation;
 
  int i;
  event=0;

  if( obj == btnCE ) {
    value = 0;
    lastval = 0;
    operands = 0;
  } else if( obj == btnC ) {
    if( operands > 0 )
      operands--;
    if( operands > 1 )
      value = lastval;
  } else if( obj == btnBS ) {
  } else if( obj == btneq  || obj == btnadd || obj == btnsub ||
          obj == btnmul || obj == btndiv ) {
    if( operands > 1 ) {
      switch( operation ) {
      case 0: lastval = value = lastval + value; break;
      case 1: lastval = value = lastval - value; break;
      case 2: lastval = value = lastval * value; break;
      case 3: lastval = value = lastval / value; break;
      }
      operands = 1;
      if( obj != btneq ) {
      }
    }
    if( operands > 0 ) {
      if( obj == btnadd ) {
     lastval = value;
     operands++;
     operation = 0;
      } else if( obj == btnsub ) {
     lastval = value;
     operands++;
     operation = 1;
      } else if( obj == btnmul ) {
     lastval = value;
     operands++;
     operation = 2;
      } else if( obj == btndiv ) {
     lastval = value;
     operands++;
     operation = 3;
      }
    }
  } else {
    for( i = 0; i < 10; i++ )
      if( obj == btnnum[i] )
     value = value*10.0 + (float)i;
  }
   
  sprintf( answer, "%g", value );  
  windowComponentSetData( answerLabel, answer, strlen( answer ) + 1 );
  windowComponentDraw( answerLabel );
 



}



int main( int argc, char *argv[] ) {
  argc =0;
  argv =0;
 
 
  componentParameters params;

 

  // Create a new window
  top = windowNew(multitaskerGetCurrentProcessId(), "Calc");
  if( !top )
    exit( ERR_NOTINITIALIZED );

  bzero(&params, sizeof(componentParameters));
  params.gridWidth = 4;
  params.gridHeight = 1;
  params.padLeft = 5;
  params.padRight = 5;
  params.padTop = 5;
  params.padBottom = 5;
  params.orientationX = orient_left;
  params.orientationY = orient_middle;
  params.useDefaultForeground = 1;
  params.useDefaultBackground = 1;
 
  answerLabel = windowNewTextLabel( top, "0", &params );

  params.gridWidth = 1;
  params.gridY = 1;
  params.orientationX = orient_center;

  btnCE = windowNewButton( top, "CE", NULL, &params );
  params.gridX++;
  btnC = windowNewButton( top, "C", NULL, &params );
  params.gridX++;
  btnBS = windowNewButton( top, "BS", NULL, &params );
  params.gridX++;
  btneq = windowNewButton( top, "=", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[7] = windowNewButton( top, "7", NULL, &params );
  params.gridX++;
  btnnum[6] = windowNewButton( top, "8", NULL, &params );
  params.gridX++;
  btnnum[5] = windowNewButton( top, "9", NULL, &params );
  params.gridX++;
  btndiv = windowNewButton( top, "/", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[4] = windowNewButton( top, "4", NULL, &params );
  params.gridX++;
  btnnum[5] = windowNewButton( top, "5", NULL, &params );
  params.gridX++;
  btnnum[6] = windowNewButton( top, "6", NULL, &params );
  params.gridX++;
  btnmul = windowNewButton( top, "*", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[1] = windowNewButton( top, "1", NULL, &params );
  params.gridX++;
  btnnum[2] = windowNewButton( top, "2", NULL, &params );
  params.gridX++;
  btnnum[3] = windowNewButton( top, "3", NULL, &params );
  params.gridX++;
  btnsub = windowNewButton( top, "-", NULL, &params );

  params.gridY++;
  params.gridX = 0;

  btnnum[0] = windowNewButton( top, "0", NULL, &params );
  params.gridX++;
  btnsgn = windowNewButton( top, "-+", NULL, &params );
  params.gridX++;
  btndot = windowNewButton( top, ".", NULL, &params );
  params.gridX++;
  btnadd = windowNewButton( top, "+", NULL, &params );

  windowRegisterEventHandler( top, &eventHandler);

  windowGuiRun();
  return 1;
}

Hi AronRubin ,

Are u able to solve the problem?

The code is already pasted above.

Thanks in advance

Hi AronRubin,

u r not around?

I have tried by hard code the variable

value = 7.045;
    sprintf( answer, "%f", value );
    windowComponentSetData( textArea, answer, strlen( answer ) );

Somehow i think the sprintf doesnt work

How?

Does the following work?

//sprintf( answer, "%f", value );
answer = "7.045";
windowComponentSetData( textArea, answer, strlen( answer ) );

At first there is a compile error
incompatible type
answer = "7.045" - > this line

then i tried strcpy(answer, "7.045");

strcpy(answer, "7.045");
windowComponentSetData( textArea, answer, strlen( answer ) );
This works.. the textArea will be replace

But
sprintf(answer, "%g", value);
windowComponentSetData( textArea, answer, strlen( answer ) );
doesnt work

Wat wrong with the sprintf?

maybe that sprintf is broken. try including this function and using it instead:
char *gcvt(double number, size_t ndigit, char *buf)
{
      int sign, decpt;
      register char *p1, *p2;
      register i;

      p1 = ecvt(number, ndigit, &decpt, &sign);
      p2 = buf;
      if (sign)
            *p2++ = '-';
      for (i=ndigit-1; i>0 && p1[i]=='0'; i--)
            ndigit--;
      if ((decpt >= 0 && decpt-ndigit > 4)
       || (decpt < 0 && decpt < -3)) { /* use E-style */
            decpt--;
            *p2++ = *p1++;
            *p2++ = '.';
            for (i=1; i<ndigit; i++)
                  *p2++ = *p1++;
            *p2++ = 'e';
            if (decpt<0) {
                  decpt = -decpt;
                  *p2++ = '-';
            } else
                  *p2++ = '+';
            if (decpt/100 > 0)
              *p2++ = decpt/100 + '0';
            if (decpt/10 > 0)
              *p2++ = (decpt%100)/10 + '0';
            *p2++ = decpt%10 + '0';
      } else {
            if (decpt<=0) {
                  if (*p1!='0')
                        *p2++ = '.';
                  while (decpt<0) {
                        decpt++;
                        *p2++ = '0';
                  }
            }
            for (i=1; i<=ndigit; i++) {
                  *p2++ = *p1++;
                  if (i==decpt)
                        *p2++ = '.';
            }
            if (ndigit<decpt) {
                  while (ndigit++<decpt)
                        *p2++ = '0';
                  *p2++ = '.';
            }
      }
      if (p2[-1]=='.')
            p2--;
      *p2 = '\0';
      return(buf);
}

Sorry you need this too:
/*
 * $Id: cvt.c,v 1.2 1995/06/01 01:19:05 chuck Exp $
 *
 * cvt.c - IEEE floating point formatting routines for FreeBSD
 * from GNU libc-4.6.27
 */

#include <stdlib.h>
#include <math.h>

#undef      IEEE

/*
 *      ecvt converts to decimal
 *      the number of digits is specified by ndigit
 *      decpt is set to the position of the decimal point
 *      sign is set to 0 for positive, 1 for negative
 */

#ifdef IEEE

static inline int __isspecial(double f, char *bp)
{
      union ieee754_double *ip = (union ieee754_double *) &f;

      if ((ip->ieee.exponent & 0x7ff) != 0x7ff)
            return(0);
      if (ip->ieee.mantissa0 || ip->ieee.mantissa1)
            strcpy(bp, "NaN");
      else if (ip->ieee.negative)
            strcpy(bp, "-Infinity");
      else
            strcpy(bp, "Infinity");
      return(1);
}

#define      NDIG      512
#else
#define      NDIG      80
#endif

static char *cvt(double arg, size_t ndigits, int *decpt, int *sign, int eflag) {
      register int r2;
      double fi, fj;
      register char *p, *p1;
      static char buf[NDIG];

#ifdef IEEE
      /* XXX */
      if (__isspecial(arg, buf))
            return(buf);
#endif
      if (ndigits>=NDIG-1)
            ndigits = NDIG-2;
      r2 = 0;
      *sign = 0;
      p = &buf[0];
      if (arg<0) {
            *sign = 1;
            arg = -arg;
      }
      arg = modf(arg, &fi);
      p1 = &buf[NDIG];
      /*
       * Do integer part
       */
      if (fi != 0) {
            p1 = &buf[NDIG];
            while (fi != 0) {
                  fj = modf(fi/10, &fi);
                  *--p1 = (int)((fj+.03)*10) + '0';
                  r2++;
            }
            while (p1 < &buf[NDIG])
                  *p++ = *p1++;
      } else if (arg > 0) {
            while ((fj = arg*10) < 1) {
                  arg = fj;
                  r2--;
            }
      }
      p1 = &buf[ndigits];
      if (eflag==0)
            p1 += r2;
      *decpt = r2;
      if (p1 < &buf[0]) {
            buf[0] = '\0';
            return(buf);
      }
      while (p<=p1 && p<&buf[NDIG]) {
            arg *= 10;
            arg = modf(arg, &fj);
            *p++ = (int)fj + '0';
      }
      if (p1 >= &buf[NDIG]) {
            buf[NDIG-1] = '\0';
            return(buf);
      }
      p = p1;
      *p1 += 5;
      while (*p1 > '9') {
            *p1 = '0';
            if (p1>buf)
                  ++*--p1;
            else {
                  *p1 = '1';
                  (*decpt)++;
                  if (eflag==0) {
                        if (p>buf)
                              *p = '0';
                        p++;
                  }
            }
      }
      *p = '\0';
      return(buf);
}

char *ecvt(double arg, size_t ndigits, int *decpt, int *sign) {
      return(cvt(arg, ndigits, decpt, sign, 1));
}

char *fcvt(double arg, size_t ndigits, int *decpt, int *sign) {
      return(cvt(arg, ndigits, decpt, sign, 0));
}

So i include all above code to my calc.c?

how to use the gcvt? can give me an example?

There is a error in function 'gcvt'

warning : comparison between signed and unsigned.

in visopsys i cannot ignore the warning, else i cannot compile.

This is the sprintf of visospsy. i think it dont support %g. I use %d and it can be display.

Can we edit the sorintf function to support %g?

// This is the standard "sprintf" function, as found in standard C libraries

#include <stdio.h>
#include <stdarg.h>
#include <sys/cdefs.h>


int sprintf(char *output, const char *format, ...)
{
  // This function will construct a single string out of the format
  // string and arguments that are passed.  Returns the number of
  // characters copied to the output string.

  va_list list;
  int outputLen = 0;

  // Initialize the argument list
  va_start(list, format);

  // Fill out the output line based on
  outputLen = _expandFormatString(output, format, list);

  va_end(list);

  // Return the number of characters we wrote to the string
  return (outputLen);
}