参考资料：
http://blog.csdn.net/kaku_you/archiv.../31/15437.aspx
http://users.actcom.co.il/~choo/lupg...ogramming.html
例程我考过来在下面了，也可以看参考资料的最后。
主要有两点疑问：
1、为什么替换了字体名字输出显示就不行了（中英文都不行）？
2、想要输出中文需要怎么样稍稍改改？
这里我替换了变量"font_name"，如果我直接给他指定一个字体的完整信息的话窗口会什么都画不出来，用这样的 " * " 来代替话英文字符串是可以画出来的，中文字符串是乱码，想要输出中文好像还要稍稍处理一下，但是我不知道如何做，请大家指教
109 XFontStruct* font_info; /* Font structure, used for drawing text. */
110 char* font_name = "*-helvetica-*-12-*"; /* font to use for drawing text. */
111 //char* font_name = "-adobe-helvetica-medium-o-normal--12-120-75-75-p-67-iso10646-1";
。。。
145 font_info = XLoadQueryFont(display, font_name);
146 if (!font_info) {
147 fprintf(stderr, "XLoadQueryFont: failed loading font '%s'\n", font_name);
148 exit(-1);
149 }
例程：
代码： 全选
/*
* simple-text.c - demonstrate drawing of text strings on a window. All
* drawings are done in black color over a white background.
*/
#include <X11/Xlib.h>
#include <stdio.h>
#include <stdlib.h> /* getenv(), etc. */
#include <string.h>
#include <unistd.h> /* sleep(), etc. */
/*
* function: create_simple_window. Creates a window with a white background
* in the given size.
* input: display, size of the window (in pixels), and location of the window
* (in pixels).
* output: the window's ID.
* notes: window is created with a black border, 2 pixels wide.
* the window is automatically mapped after its creation.
*/
Window create_simple_window(Display* display, int width, int height, int x, int y)
{
int screen_num = DefaultScreen(display);
int win_border_width = 2;
Window win;
/* create a simple window, as a direct child of the screen's */
/* root window. Use the screen's black and white colors as */
/* the foreground and background colors of the window, */
/* respectively. Place the new window's top-left corner at */
/* the given 'x,y' coordinates. */
win = XCreateSimpleWindow(display, RootWindow(display, screen_num),
x, y, width, height, win_border_width,
BlackPixel(display, screen_num),
WhitePixel(display, screen_num));
/* make the window actually appear on the screen. */
XMapWindow(display, win);
/* flush all pending requests to the X server. */
XFlush(display);
return win;
}
GC create_gc(Display* display, Window win, int reverse_video)
{
GC gc; /* handle of newly created GC. */
unsigned long valuemask = 0; /* which values in 'values' to */
/* check when creating the GC. */
XGCValues values; /* initial values for the GC. */
unsigned int line_width = 2; /* line width for the GC. */
int line_style = LineSolid; /* style for lines drawing and */
int cap_style = CapButt; /* style of the line's edje and */
int join_style = JoinBevel; /* joined lines. */
int screen_num = DefaultScreen(display);
gc = XCreateGC(display, win, valuemask, &values);
if (gc < 0) {
fprintf(stderr, "XCreateGC: \n");
}
/* allocate foreground and background colors for this GC. */
if (reverse_video) {
XSetForeground(display, gc, WhitePixel(display, screen_num));
XSetBackground(display, gc, BlackPixel(display, screen_num));
}
else {
XSetForeground(display, gc, BlackPixel(display, screen_num));
XSetBackground(display, gc, WhitePixel(display, screen_num));
}
/* define the style of lines that will be drawn using this GC. */
XSetLineAttributes(display, gc,
line_width, line_style, cap_style, join_style);
/* define the fill style for the GC. to be 'solid filling'. */
XSetFillStyle(display, gc, FillSolid);
return gc;
}
void list_fonts(Display *display)
{
int font_count, i;
char **fonts;
//列出所有GB2312
printf("All fonts on this server:\n");
fonts = XListFonts(display, "*-helvetica-*-12-*", 1000, &font_count);
for(i=0; i<font_count; i++)
printf("%s\n", fonts[i]);
XFreeFontNames(fonts);
}
int main(int argc, char* argv[])
{
Display* display; /* pointer to X Display structure. */
int screen_num; /* number of screen to place the window on. */
Window win; /* pointer to the newly created window. */
unsigned int display_width,
display_height; /* height and width of the X display. */
unsigned int win_width,
win_height; /* height and width for the new window. */
char* display_name = getenv("DISPLAY"); /* address of the X display. */
GC gc; /* GC (graphics context) used for drawing */
/* in our window. */
XFontStruct* font_info; /* Font structure, used for drawing text. */
char* font_name = "*-helvetica-*-12-*"; /* font to use for drawing text. */
//char* font_name = "-adobe-helvetica-medium-o-normal--12-120-75-75-p-67-iso10646-1";
/* open connection with the X server. */
display = XOpenDisplay(display_name);
if (display == NULL) {
fprintf(stderr, "%s: cannot connect to X server '%s'\n",
argv[0], display_name);
exit(1);
}
/* list all fonts */
list_fonts(display);
/* get the geometry of the default screen for our display. */
screen_num = DefaultScreen(display);
display_width = DisplayWidth(display, screen_num);
display_height = DisplayHeight(display, screen_num);
/* make the new window occupy 1/9 of the screen's size. */
win_width = (display_width / 3);
win_height = (display_height / 3);
//printf("window width - '%d'; height - '%d'\n", win_width, win_height);
/* create a simple window, as a direct child of the screen's */
/* root window. Use the screen's white color as the background */
/* color of the window. Place the new window's top-left corner */
/* at the given 'x,y' coordinates. */
win = create_simple_window(display, win_width, win_height, 0, 0);
/* allocate a new GC (graphics context) for drawing in the window. */
gc = create_gc(display, win, 0);
XSync(display, False);
/* try to load the given font. */
font_info = XLoadQueryFont(display, font_name);
if (!font_info) {
fprintf(stderr, "XLoadQueryFont: failed loading font '%s'\n", font_name);
exit(-1);
}
/* assign the given font to our GC. */
XSetFont(display, gc, font_info->fid);
{
/* variables used for drawing the text strings. */
int x, y;
char* text_string;
int string_width;
int font_height;
/* find the height of the characters drawn using this font. */
font_height = font_info->ascent + font_info->descent;
//setlocale("LANG", "");
/* draw a "hello world" string on the top-left side of our window. */
text_string = "hello world";
x = 0;
y = font_height;
XDrawString(display, win, gc, x, y, text_string, strlen(text_string));
/* draw a "middle of the road" string in the middle of our window. */
//text_string = "middle of the road";
text_string = "中间是中文";
/* find the width, in pixels, of the text that will be drawn using */
/* the given font. */
string_width = XTextWidth(font_info, text_string, strlen(text_string));
x = (win_width - string_width) / 2;
y = (win_height + font_height) / 2;
XDrawString(display, win, gc, x, y, text_string, strlen(text_string));
}
/* flush all pending requests to the X server. */
XFlush(display);
/* make a delay for a short period. */
sleep(3);
/* close the connection to the X server. */
XCloseDisplay(display);
return 0;
}