SWI-Prolog has no provisions for graphical applications itself. The standard graphical environment to be used with SWI-Prolog is XPCE. XPCE/SWI-Prolog provides an interactive graphical develpment platform that is portable over many Unix/X11 implementations as well as MS-Windows (3.1) and Windows-NT (3.5).
XPCE is a licenced product. A fully functional free demo version for PC/Linux is available from ftp://swi.psy.uva.nl/pub/xpce/linux , for more information see URL
http://www.swi.psy.uva.nl/projects/xpce/home.htmlor contact xpce-request@swi.psy.uva.nl.