#include <stdio.h>
#include <stdlib.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xos.h>
#include <X11/Xatom.h>

int main(int argc, char *argv[])
{
    Display *dpy;
    int screen;
    Window win;
    Window childWin;
    XEvent event;

    /* Text declaration vars */
    Font fid;

    XFontStruct *font;
    XTextItem ti[1];

    dpy = XOpenDisplay(NULL);

    if(dpy == NULL)
    {
        fprintf(stderr, "Cannot open display\n");
        exit(1);
    }

    screen = DefaultScreen(dpy);

    /* parent window */
    win = XCreateSimpleWindow(dpy, RootWindow(dpy, screen),
            100, 100, 500, 300,
            1, BlackPixel(dpy, screen), WhitePixel(dpy, screen));

    XSelectInput(dpy, win, ExposureMask | KeyPressMask);
    XMapWindow(dpy, win);

    /* child window */
    childWin = XCreateSimpleWindow(dpy, win,
            20, 20, 200, 100,
            1, BlackPixel(dpy, screen), WhitePixel(dpy, screen));

    XSelectInput(dpy, childWin, ExposureMask | KeyPressMask);
    XMapWindow(dpy, childWin);

    while(1)
    {
        XNextEvent(dpy, &event);
        if(event.xany.window == childWin){

            if(event.type == Expose)
            {
                XDrawLine(dpy, childWin, DefaultGC(dpy,
                            screen), 10, 10, 60, 60);

                font = XLoadQueryFont(dpy, "-*-helvetica-*-r-*-*-14-*-*-*-*-*-*-*");
                ti[0].chars = "Press Me!";
                ti[0].nchars = 9;
                ti[0].delta = 0;
                ti[0].font = font->fid;
                XDrawText(dpy, childWin, DefaultGC(dpy, screen),
                        (200 - XTextWidth(font, ti[0].chars, ti[0].nchars))/2,
                        (100 - (font->ascent+font->descent))/2+font->ascent,
                        ti, 1);
                XUnloadFont(dpy, font->fid);


            }

        }
    }


    return 0;
}