Source Code for Xlib Program Example
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#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xos.h>
#include <stdio.h>
#include "bitmaps/icon_bitmap"
#define BITMAPDEPTH 1
Display *display;
int screen;
/* values for window_size in main */
#define SMALL 1
#define OK 0
void main(argc, argv)
int argc;
char **argv;
{
Window win;
unsigned int width, height, display_width, display_height;
int x = 0, y = 0;
unsigned int border_width = 4;
char *window_name = "Basic Window Program";
char *icon_name = "basicwin";
Pixmap icon_pixmap;
XSizeHints size_hints;
XEvent report;
GC gc;
XFontStruct *font_info;
char *display_name = NULL;
int window_size = 0;
if ((display=XOpenDisplay(display_name)) == NULL)
{
fprintf(stderr,"basicwin: cannot connect to X server %s\n",
XDisplayName(display_name));
exit(-1);
}
screen = DefaultScreen(display);
display_width = DisplayWidth(display,screen);
display_height = DisplayHeight(display,screen);
width = display_width/3;
height = display_height/4;
win = XCreateSimpleWindow(display, RootWindow(display,screen),
x, y, width, height, border_width,
BlackPixel(display,screen),
WhitePixel(display,screen));
icon_pixmap = XCreateBitmapFromData(display, win, icon_bitmap_bits,
icon_bitmap_width, icon_bitmap_height);
size_hints.flags = PPosition | PSize | PMinSize;
size_hints.x = x;
size_hints.y = y;
size_hints.width = width;
size_hints.height = height;
size_hints.min_width = 350;
size_hints.min_height = 250;
XSetStandardProperties(display, win, window_name, icon_name, icon_pixmap,
argv, argc, &size_hints);
XSelectInput(display, win, ExposureMask |
KeyPressMask |
ButtonPressMask |
StructureNotifyMask);
load_font(&font_info);
get_GC(win, &gc, font_info);
XMapWindow(display, win);
while (1)
{
XNextEvent(display, &report);
switch (report.type)
{
case Expose:
while (XCheckTypedEvent(display, Expose, &report))
;
if (window_size == SMALL)
TooSmall(win, gc, font_info);
else
{
draw_text(win, gc, font_info, width, height);
draw_graphics(win, gc, width, height);
}
break;
case ConfigureNotify:
width = report.xconfigure.width;
height = report.xconfigure.height;
if (width < size_hints.min_width || height < size_hints.min_height)
window_size = SMALL;
else
window_size = OK;
break;
case ButtonPress:
case KeyPress:
XUnloadFont(display, font_info->fid);
XFreeGC(display, gc);
XCloseDisplay(display);
exit(1);
break;
default:
break;
}
}
}
get_GC(win, gc, font_info)
Window win;
GC *gc;
XFontStruct *font_info;
{
unsigned long valuemask = 0;
XGCValues values;
unsigned int line_width = 1;
int line_style = LineSolid; /*LineOnOffDash;*/
int cap_style = CapButt;
int join_style = JoinMiter;
int dash_offset = 0;
static char dash_list[] = {20, 40};
int list_length = sizeof(dash_list);
*gc = XCreateGC(display, win, valuemask, &values);
XSetFont(display, *gc, font_info->fid);
XSetForeground(display, *gc, BlackPixel(display,screen));
XSetLineAttributes(display, *gc, line_width, line_style, cap_style, join_style);
XSetDashes(display, *gc, dash_offset, dash_list, list_length);
}
load_font(font_info)
XFontStruct **font_info;
{
char *fontname = "9x15";
if ((*font_info=XLoadQueryFont(display,fontname)) == NULL)
{
printf("stderr, basicwin: cannot open 9x15 font\n");
exit(-1);
}
}
draw_text(win, gc, font_info, win_width, win_height)
Window win;
GC gc;
XFontStruct *font_info;
unsigned int win_width, win_height;
{
int y = 20;
char *string1 = "Hi! I'm a window, who are you?";
char *string2 = "To terminate program; Press any key";
char *string3 = "or button while in this window.";
char *string4 = "Screen Dimensions:";
int len1, len2, len3, len4;
int width1, width2, width3;
char cd_height[50], cd_width[50], cd_depth[50];
int font_height;
int y_offset, x_offset;
len1 = strlen(string1);
len2 = strlen(string2);
len3 = strlen(string3);
width1 = XTextWidth(font_info, string1, len1);
width2 = XTextWidth(font_info, string2, len2);
width3 = XTextWidth(font_info, string3, len3);
XDrawString(display, win, gc, (win_width-width1)/2, y, string1, len1);
XDrawString(display, win, gc, (win_width-width2)/2, (int)(win_height-35), string2, len2);
XDrawString(display, win, gc, (win_width-width3)/2, (int)(win_height-15), string3, len3);
sprintf(cd_height,"Height - %d pixels", DisplayHeight(display,screen));
sprintf(cd_width,"Width - %d pixels", DisplayWidth(display,screen));
sprintf(cd_depth,"Depth - %d plane(s)", DefaultDepth(display,screen));
len4 = strlen(string4);
len1 = strlen(cd_height);
len2 = strlen(cd_width);
len3 = strlen(cd_depth);
font_height = font_info->max_bounds.ascent +
font_info->max_bounds.descent;
y_offset = win_height/2 - font_height - font_info->max_bounds.descent;
x_offset = (int) win_width/4;
XDrawString(display, win, gc, x_offset, y_offset, string4, len4);
y_offset += font_height;
XDrawString(display, win, gc, x_offset, y_offset, cd_height, len1);
y_offset += font_height;
XDrawString(display, win, gc, x_offset, y_offset, cd_width, len2);
y_offset += font_height;
XDrawString(display, win, gc, x_offset, y_offset, cd_depth, len3);
}
draw_graphics(win, gc, window_width, window_height)
Window win;
GC gc;
unsigned int window_width, window_height;
{
int x,y;
unsigned int width, height;
height = window_height/2;
width = 3 * window_width/4;
x = window_width/2 - width/2;
y = window_height/2 - height/2;
XDrawRectangle(display, win, gc, x, y, width, height);
}
TooSmall(win, gc, font_info)
Window win;
GC gc;
XFontStruct *font_info;
{
char *string1 = "Too Small";
int x,y;
y = font_info->max_bounds.ascent + 2;
x = 2;
XDrawString(display, win, gc, x, y, string1, strlen(string1));
}
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