以下是xlib第一个完比较完整基本窗口例子，语句多，还有好多个警告和错误，本人初学xlib，不知道语句间层次关系，用法，怎样修改才能改正确
向高人求教了
//basicwin -- in its entirety
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xos.h>
#include <X11/Xatom.h>
#include <stdio.h>
#include "bitmaps/icon_bitmap"
#define BITMAPDEPTH 1
#define TOO_SMALL 0
#define BIG_ENOUGH 1
/* These are used as arguments to nearly every Xlib routine, so it
* saves routine arguments to declare them global; if there were
* additional source files, they would be declared extern there */
Display *display;
int screen_num;
/* progname is the string by which this program was invoked; this
* is global because it is needed in most application functions */
static char *progname;
void main(argc, argv)
int argc;
char **argv;
{
Window win;
unsigned int width, height; /* Window size */
int x, y; /* Window position */
unsigned int border_width = 4; /* Four pixels */
unsigned int display_width, display_height;
unsigned int icon_width, icon_height;
char *window_name = "Basic Window Program";
char *icon_name = "basicwin";
Pixmap icon_pixmap;
XSizeHints *size_hints;
XIconSize *size_list;
XWMHints *wm_hints;
XClassHint *class_hints;
XTextProperty windowName, iconName;
int count;
XEvent report;
GC gc;
XFontStruct *font_info;
char *display_name = NULL;
int window_size = 0; /* BIG_ENOUGH or TOO_SMALL to
* display contents */
progname = argv[0];
if (!(size_hints = XAllocSizeHints())) {
fprintf(stderr, "%s: failure allocating memory, progname);
exit(0);
}
if (!(wm_hints = XAllocWMHints())) {
fprintf(stderr, "%s: failure allocating memory, progname);
exit(0);
}
if (!(class_hints = XAllocClassHint())) {
fprintf(stderr, "%s: failure allocating memory, progname);
exit(0);
}
/* Connect to X server */
if ( (display=XOpenDisplay(display_name)) == NULL )
{
(void) fprintf( stderr, "%s: cannot connect to X server %s\n",
progname, XDisplayName(display_name));
exit( -1 );
}
/* Get screen size from display structure macro */
screen_num = DefaultScreen(display);
display_width = DisplayWidth(display, screen_num);
display_height = DisplayHeight(display, screen_num);
/* Note that in a real application, x and y would default
* to 0 but would be settable from the command line or
* resource database */
x = y = 0;
/* Size window with enough room for text */
width = display_width/3, height = display_height/4;
/* Create opaque window */
win = XCreateSimpleWindow(display, RootWindow(display,screen_num),
x, y, width, height, border_width, BlackPixel(display,
screen_num), WhitePixel(display,screen_num));
/* Get available icon sizes from window manager */
if (XGetIconSizes(display, RootWindow(display,screen_num),
&size_list, &count) == 0)
(void) fprintf( stderr, "%s: Window manager didn't set \
icon sizes - using default.\n", progname);
else {
;
/* A real application would search through size_list
* here to find an acceptable icon size and then
* create a pixmap of that size; this requires that
* the application have data for several sizes of icons */
}
/* Create pixmap of depth 1 (bitmap) for icon */
icon_pixmap = XCreateBitmapFromData(display, win,
icon_bitmap_bits, icon_bitmap_width,
icon_bitmap_height);
/* Set size hints for window manager; the window manager
* may override these settings */
/* Note that in a real application, if size or position
* were set by the user, the flags would be USPosition
* and USSize and these would override the window manager's
* preferences for this window */
/* x, y, width, and height hints are now taken from
* the actual settings of the window when mapped; note
* that PPosition and PSize must be specified anyway */
size_hints->flags = PPosition | PSize | PMinSize;
size_hints->min_width = 300;
size_hints->min_height = 200;
/* These calls store window_name and icon_name into
* XTextProperty structures and set their other fields
* properly */
if (XStringListToTextProperty(&window_name, 1, &windowName) == 0) {
(void) fprintf( stderr, "%s: structure allocation for \
windowName failed.\n", progname);
exit(-1);
}
if (XStringListToTextProperty(&icon_name, 1, &iconName) == 0) {
(void) fprintf( stderr, "%s: structure allocation for \
iconName failed.\n", progname);
exit(-1);
}
wm_hints->initial_state = NormalState;
wm_hints->input = True;
wm_hints->icon_pixmap = icon_pixmap;
wm_hints->flags = StateHint | IconPixmapHint | InputHint;
class_hints->res_name = progname;
class_hints->res_class = "Basicwin";
XSetWMProperties(display, win, &windowName, &iconName,
argv, argc, size_hints, wm_hints,
class_hints);
}
/* Select event types wanted */
XSelectInput(display, win, ExposureMask | KeyPressMask |
ButtonPressMask | StructureNotifyMask);
load_font(&font_info);
/* Create GC for text and drawing */
getGC(win, &gc, font_info);
/* Display window */
XMapWindow(display, win);
/* Get events, use first to display text and graphics */
while (1) {
XNextEvent(display, &report);
switch (report.type) {
case Expose:
/* Unless this is the last contiguous expose,
* don't draw the window */
if (report.xexpose.count != 0)
break;
/* If window too small to use */
if (window_size == TOO_SMALL)
TooSmall(win, gc, font_info);
else {
/* Place text in window */
place_text(win, gc, font_info, width, height);
/* Place graphics in window */
place_graphics(win, gc, width, height);
}
break;
case ConfigureNotify:
/* Window has been resized; change width
* and height to send to place_text and
* place_graphics in next Expose */
width = report.xconfigure.width;
height = report.xconfigure.height;
if ((width < size_hints->min_width) ||
(height < size_hints->min_height))
window_size = TOO_SMALL;
else
window_size = BIG_ENOUGH;
break;
case ButtonPress:
/* Trickle down into KeyPress (no break) */
case KeyPress:
XUnloadFont(display, font_info->fid);
XFreeGC(display, gc);
XCloseDisplay(display);
exit(1);
default:
/* All events selected by StructureNotifyMask
* except ConfigureNotify are thrown away here,
* since nothing is done with them */
break;
} /* End switch */
} /* End while */
}
getGC(win, gc, font_info)
Window win;
GC *gc;
XFontStruct *font_info;
{
unsigned long valuemask = 0; /* Ignore XGCvalues and
* use defaults */
XGCValues values;
unsigned int line_width = 6;
int line_style = LineOnOffDash;
int cap_style = CapRound;
int join_style = JoinRound;
int dash_offset = 0;
static char dash_list[] = {12, 24};
int list_length = 2;
/* Create default Graphics Context */
*gc = XCreateGC(display, win, valuemask, &values);
/* Specify font */
XSetFont(display, *gc, font_info->fid);
/* Specify black foreground since default window background
* is white and default foreground is undefined */
XSetForeground(display, *gc, BlackPixel(display,screen_num));
/* Set line attributes */
XSetLineAttributes(display, *gc, line_width, line_style,
cap_style, join_style);
/* Set dashes */
XSetDashes(display, *gc, dash_offset, dash_list, list_length);
}
load_font(font_info)
XFontStruct **font_info;
{
char *fontname = "9x15";
/* Load font and get font information structure */
if ((*font_info = XLoadQueryFont(display,fontname)) == NULL)
{
(void) fprintf( stderr, "%s: Cannot open 9x15 font\n",
progname);
exit( -1 );
}
}
place_text(win, gc, font_info, win_width, win_height)
Window win;
GC gc;
XFontStruct *font_info;
unsigned int win_width, win_height;
{
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 initial_y_offset, x_offset;
/* Need length for both XTextWidth and XDrawString */
len1 = strlen(string1);
len2 = strlen(string2);
len3 = strlen(string3);
/* Get string widths for centering */
width1 = XTextWidth(font_info, string1, len1);
width2 = XTextWidth(font_info, string2, len2);
width3 = XTextWidth(font_info, string3, len3);
font_height = font_info->ascent + font_info->descent;
/* Output text, centered on each line */
XDrawString(display, win, gc, (win_width - width1)/2,
font_height,
string1, len1);
XDrawString(display, win, gc, (win_width - width2)/2,
(int)(win_height - (2 * font_height)),
string2, len2);
XDrawString(display, win, gc, (win_width - width3)/2,
(int)(win_height - font_height),
string3, len3);
/* Copy numbers into string variables */
(void) sprintf(cd_height, " Height - %d pixels",
DisplayHeight(display,screen_num));
(void) sprintf(cd_width, " Width - %d pixels",
DisplayWidth(display,screen_num));
(void) sprintf(cd_depth, " Depth - %d plane(s)",
DefaultDepth(display, screen_num));
/* Reuse these for same purpose */
len4 = strlen(string4);
len1 = strlen(cd_height);
len2 = strlen(cd_width);
len3 = strlen(cd_depth);
/* To center strings vertically, we place the first string
* so that the top of it is two font_heights above the center
* of the window; since the baseline of the string is what
* we need to locate for XDrawString and the baseline is
* one font_info -> ascent below the top of the character,
* the final offset of the origin up from the center of
* the window is one font_height + one descent */
initial_y_offset = win_height/2 - font_height -
font_info->descent;
x_offset = (int) win_width/4;
XDrawString(display, win, gc, x_offset, (int) initial_y_offset,
string4,len4);
XDrawString(display, win, gc, x_offset, (int) initial_y_offset +
font_height,cd_height,len1);
XDrawString(display, win, gc, x_offset, (int) initial_y_offset +
2 * font_height,cd_width,len2);
XDrawString(display, win, gc, x_offset, (int) initial_y_offset +
3 * font_height,cd_depth,len3);
}
place_graphics(win, gc, window_width, window_height)
Window win;
GC gc;
unsigned int window_width, window_height;
{
int x, y;
int width, height;
height = window_height/2;
width = 3 * window_width/4;
x = window_width/2 - width/2; /* Center */
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 y_offset, x_offset;
y_offset = font_info->ascent + 2;
x_offset = 2;
/* Output text, centered on each line */
XDrawString(display, win, gc, x_offset, y_offset, string1,
strlen(string1));
}
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