Example 1.3 of the tutorial : Controling events
[Tutorial]

More events, best terminaison. More... In some case, EvntAdd() is better than EvntAttach()

/*
 * WinDom: a high level GEM library
 * Copyright (c) 1997-2006 windom authors (see AUTHORS file)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 * $Source: /cvsroot/windom/htdocs/doc/html/group__tut1__3.html,v $
 *
 * CVS info:
 *   $Author: bercegeay $
 *   $Date: 2006/06/22 11:58:28 $
 *   $Revision: 1.5 $
 */


#include <stdlib.h>
#include <windom.h>

struct circle {
  short color;
  short interior;
  short style;
};

static
void __CDECL evnt_destroy_circle( WINDOW *win, short buff[8], void *C) {
        free( win->info);
        free( C);  /* free memory */
}

static
void __CDECL evnt_draw_circle( WINDOW *win, short buff[8], void *data) {
    short x, y, w, h;
    struct circle *circ = (struct circle *) data;

    /* Get the workspace coordinates */
    WindGet( win, WF_WORKXYWH, &x, &y, &w, &h);

    /* Set some VDI attributes */
    vsf_color( win->graf->handle, circ->color);
    vsf_interior( win->graf->handle, circ->interior);
    vsf_style( win->graf->handle, circ->style);

    /* Drawing the circle */
    v_circle( win->graf->handle, x+w/2-1, y+h/2-1, MIN( w, h)/3);
}

static void update_info( WINDOW *win, struct circle *circ) {
    sprintf( win->info, "color:%d interior:%d style:%d", circ->color, circ->interior, circ->style);
    WindSetStr( win, WF_INFO, win->info);
}

static
void __CDECL evnt_keybd_circle( WINDOW *win, short buff[8], void *data) {
    /* Get the real ascii code of a key using its scancode */
    int key = keybd2ascii( evnt.keybd, evnt.mkstate & (K_LSHIFT|K_RSHIFT));
    struct circle *circ = (struct circle *) data;
    switch( key) {
    case 'q':
    case 'Q':
         /* Quit application */
         if( FormAlert( 1, FA_QUESTION "[Really quit ?][Yes|No]") == 1)
             ApplWrite( _AESapid, AP_TERM, 0, 0, 0, 0, 0);
         break;
    case 'u':
    case 'U':
         /* close window */
         ApplWrite( _AESapid, WM_CLOSED, win->handle, 0, 0, 0, 0);
         break;
    case 'w':
    case 'W':
         /* cycle window */
         WindSet( win, WF_BOTTOM, win->handle,0,0,0);
         break;
         /* change color */
    case '-':
         circ->color = (--circ->color+16)%16;
         update_info(win,circ);
         snd_rdw( win);
         break;
    case '+':
         circ->color = ++circ->color%16;
         update_info(win,circ);
         snd_rdw( win);
         break;
    }
}

WINDOW *WindCircle( int attr, int color, int interior, int style) {
    struct circle *C;
    WINDOW *win;
    char *info;

    /* Create a circle data */
    C = (struct circle *) malloc( sizeof( struct circle));
    C->color = color;
    C->interior = interior;
    C->style = style;

    /* Create the window */
    win = WindCreate( WAT_ALL, app.x, app.y, app.w, app.h);

    /* Declare new event message */
    EvntDataAdd( win, WM_REDRAW, evnt_draw_circle, C, EV_BOT);
    EvntDataAdd( win, WM_DESTROY, evnt_destroy_circle, C, EV_TOP);
    EvntDataAttach( win, WM_XKEYBD, evnt_keybd_circle, C);

    WindSetStr( win, WF_NAME, "WinDom tutorial 1-3 : drawing a circle" );
    info = (char*)malloc( 128);
    strcpy( info, "---");
    WindSetStr( win, WF_INFO, info);
    update_info(win,C);
    
    return win;
}

static
void __CDECL evnt_apterm( ) {
    while( wglb.first) {
        ApplWrite( _AESapid, WM_DESTROY, wglb.first->handle, 0, 0, 0, 0);
        EvntWindom( MU_MESAG);
    }
}

int main( void) {
    WINDOW *win;

    /* Init WinDom */
    ApplInit();

    FormAlert( 1, FA_INFO "["
           "q: quit, u: close window|"
           "w: cycle window|"
           "+/-: cycle circle color][OK]");

    /* Display a red circle ... */
    win = WindCircle( WAT_ALL, RED, FIS_SOLID, 0);
    WindOpen( win, app.x, app.y, app.w/2, app.h/2);

    /* ... and a yellow one with a nice pattern */
    win = WindCircle( WAT_ALL, YELLOW, FIS_PATTERN, 9);
    WindOpen( win, app.x+10, app.y+10, app.w/2, app.h/2);

    /* Attach a global event */
    EvntAttach( NULL, AP_TERM, evnt_apterm);

    /* Handle GEM event */
    while( wglb.first) EvntWindom( MU_MESAG|MU_KEYBD);

    /* ok, it's finish */
    ApplExit();
    return EXIT_SUCCESS;;
}

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