Category : C Source Code
Archive   : WTWG12B.ZIP
Filename : WBUTTON.C

/* wbutton.c
*--------------------- 'BUTTON' functions -----------------------------*
*
* buttons are selectable choices onscreen
* associated with either mouse or keyboard action.
*
*
* wbutton_add () - add a button to the list.
* install button handler if not yet done
* add new button to linked list
* draws the button onscreen.
*
* OPTIONS:
* WBTN_BOX = draw a box around button
*
* wbutton_frame () and
* wbutton_draw () - draw the button onscreen, draw box
* internal utilities.
* also called by
* wbutton_mark, _inactivate(), etc...
*
* event_handler () - keyboard trap routine.
*
* METHOD:
* see definition of WBUTTON above.
*
*
* these routines keep linked lists list of currently active buttons
*
* one list is maintianed for each window.
*
* when a button is added, wbutton_add()
* allocates memory for WBUTTON struct and adds to linked list.
* draws button onscreen.
*
*/
#include "wsys.h"


void wbutton_add (char *utext, int ux, int uy, int ulen,
int uval,
unsigned char ustyle )
{
WBUTTON *Bptr;


/* allocate storage and place new button in linked list
*/
Bptr = wmalloc ( sizeof (WBUTTON), "wbutton_add" );
Bptr->Bchain = w0->winbutton;
w0->winbutton = Bptr;


Bptr-> Btext = utext;
_NORMALIZE ( Bptr-> Btext );

Bptr-> Bval = uval;
Bptr-> Bstyle= ustyle;

Bptr-> Bx = ux;
Bptr-> By = uy;


Bptr->Blen = ulen;

/* compute location of end of button
* note that ulen includes terminal NULL.
* but stored value in WBUTTON strutcure is just the displayed bytes.
*
* so subtract 1 for terminal NULL .
*/
Bptr-> Bxend = ux + ulen -1;
Bptr-> Byend = uy;


wbutton_draw ( Bptr, wbuttonattr );

if ( ustyle & WBTN_BOX )
{
/* draw a box around button
*/
--(Bptr->Bx);
--(Bptr->By);
++(Bptr->Bxend);
++(Bptr->Byend);

wbutton_frame ( Bptr, SINGLE_BORDER, wreverseattr(wbuttonattr) );

}



Bptr-> Bstyle |= WBTN_ACTIVE + WBTN_BUTTON;


return; /* wbutton_add */
}




void wbutton_draw ( WBUTTON *Bptr, unsigned char new_attr )
{


unsigned char user_attr, user_x, user_y;

int len;

user_attr = wgetattr(); /* save attribute & position */
user_x = wherex();
user_y = wherey();

wsetattr ( new_attr );

/* number of onscreen bytes,
* which doesn;t count terminal NULL
*
*
*/
len = (Bptr-> Bxend) - (Bptr-> Bx);

wgoto ( Bptr->Bx, Bptr->By );

wputfl ( Bptr->Btext, len ); /* fixed len put */

wsetattr ( user_attr ); /* restore ol attribute */
wgoto ( user_x, user_y );


return; /* wbutton_draw */
}



void wbutton_frame
( WBUTTON *Bptr, unsigned char type, unsigned char color )
{
int l, t, r, b;

l = (w0-> winleft) + (Bptr->Bx);
t = (w0-> wintop ) + (Bptr->By);
r = (w0-> winleft) + (Bptr->Bxend) -1;
b = (w0-> wintop) + (Bptr->Byend);

wframe (l, t, r, b, type, color );
}


/*---------------- end of WBUTTON.C ----------------------*/