通过X11显示器获取UTF-8输入 [英] Get UTF-8 input with X11 Display
问题描述
我一直在尝试和阅读Internet上的大量资源，试图找到一种从X显示器获取UTF-8键盘(组合)输入的方法.但是我无法使其正常工作.
I've been trying and reading lots of resources on the internet, trying to find a way to get an UTF-8 keyboard (composed) input from a X Display. But I could not make it work.
I have tried the example code from this link (exaple 11-4), but no success.
我还写了一个简单的示例(如下)，试图使其工作.我的简单测试用例是打印é"，这是通过先键入"a"然后再键入e来实现的.
I also have written a simple example (below) to try to make it work. My simple test case is to print an "é", which happens by typing the acute and then the e.
怎么了?
谢谢
这是我的例子:
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xresource.h>
#include <X11/Xlocale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(int argc, char ** argv)
{
int screen_num, width, height;
unsigned long background, border;
Window win;
XEvent ev;
Display *dpy;
XIM im;
XIC ic;
char *failed_arg;
XIMStyles *styles;
XIMStyle xim_requested_style;
/* First connect to the display server, as specified in the DISPLAY
environment variable. */
if (setlocale(LC_ALL, "") == NULL) {
return 9;
}
if (!XSupportsLocale()) {
return 10;
}
if (XSetLocaleModifiers("") == NULL) {
return 11;
}
dpy = XOpenDisplay(NULL);
if (!dpy) {
fprintf(stderr, "unable to connect to display");
return 7;
}
/* these are macros that pull useful data out of the display object */
/* we use these bits of info enough to want them in their own variables */
screen_num = DefaultScreen(dpy);
background = BlackPixel(dpy, screen_num);
border = WhitePixel(dpy, screen_num);
width = 400; /* start with a small window */
height = 200;
win = XCreateSimpleWindow(dpy, DefaultRootWindow(dpy), /* display, parent */
0,0, /* x, y: the window manager will place the window elsewhere */
width, height, /* width, height */
2, border, /* border width & colour, unless you have a window manager */
background); /* background colour */
/* tell the display server what kind of events we would like to see */
XSelectInput(dpy, win, ButtonPressMask|StructureNotifyMask|KeyPressMask|KeyReleaseMask|KeymapStateMask);
/* okay, put the window on the screen, please */
XMapWindow(dpy, win);
im = XOpenIM(dpy, NULL, NULL, NULL);
if (im == NULL) {
fputs("Could not open input method\n", stdout);
return 2;
}
failed_arg = XGetIMValues(im, XNQueryInputStyle, &styles, NULL);
if (failed_arg != NULL) {
fputs("XIM Can't get styles\n", stdout);
return 3;
}
int i;
for (i = 0; i < styles->count_styles; i++) {
printf("style %d\n", styles->supported_styles[i]);
}
ic = XCreateIC(im, XNInputStyle, XIMPreeditNothing | XIMStatusNothing, XNClientWindow, win, NULL);
if (ic == NULL) {
printf("Could not open IC\n");
return 4;
}
XSetICFocus(ic);
/* as each event that we asked about occurs, we respond. In this
* case we note if the window's shape changed, and exit if a button
* is pressed inside the window */
while(1) {
XNextEvent(dpy, &ev);
switch(ev.type){
case KeymapNotify:
XRefreshKeyboardMapping(&ev.xmapping);
break;
case KeyPress:
{
int count = 0;
KeySym keysym = 0;
char buf[20];
Status status = 0;
count = Xutf8LookupString(ic, (XKeyPressedEvent*)&ev, buf, 20, &keysym, &status);
printf("count: %d\n", count);
if (status==XBufferOverflow)
printf("BufferOverflow\n");
if (count)
printf("buffer: %s\n", buf);
if (status == XLookupKeySym || status == XLookupBoth) {
printf("status: %d\n", status);
}
printf("pressed KEY: %d\n", keysym);
}
break;
case KeyRelease:
{
int count = 0;
KeySym keysym = 0;
char buf[20];
Status status = 0;
count = XLookupString((XKeyEvent*)&ev, buf, 20, &keysym, NULL);
if (count)
printf("in release buffer: %s\n", buf);
printf("released KEY: %d\n", keysym);
}
break;
case ConfigureNotify:
if (width != ev.xconfigure.width
|| height != ev.xconfigure.height) {
width = ev.xconfigure.width;
height = ev.xconfigure.height;
printf("Size changed to: %d by %d", width, height);
}
break;
case ButtonPress:
XCloseDisplay(dpy);
return 0;
}
fflush(stdout);
}
}
推荐答案
您必须执行以下操作:
if (XFilterEvent(&ev, win))
continue;
在您的事件循环中.这将运行输入法机制，如果没有它，您将获得原始X事件.例如，当您按下一个重音符号后跟一个字母键，并且不调用XFilterEvent时，您将照常获得两个KeyPress事件.但是，如果您拨打电话，将会收到三个事件.有两个原始事件，XFilterEvent(&ev, win)为此返回True.然后，通过输入法合成了一个事件，对于该事件，XFilterEvent(&ev, win)返回False.这是第三个包含重音符号的事件.
in your event loop. This runs the input method machinery, without it you will get raw X events. For example, when you press a dead accent key followed by a letter key, and do not call XFilterEvent, you will get two KeyPress events as usual. But if you do the call, you will get three events. There are two raw events, for which XFilterEvent(&ev, win) returns True. And then there is one event synthesized by the input method, for which XFilterEvent(&ev, win) returns False. It is this third event that contains the accented character.
如果既需要原始事件又需要通过输入法合成的原始事件，则当然可以代替continue来进行自己的原始事件处理.
If you want both raw events and those synthesized by the input method, you can of course do your own raw event processing instead of continue.
请注意，您需要buf[count] = 0;才能正确打印buf(或显式使用长度)，Xutf8LookupString不会以空值终止其输出.
Note you will need buf[count] = 0; in order to print buf correctly (or explicitly use a length), Xutf8LookupString doesn't null-terminate its output.
最后，如注释中所述，对于X11的最新版本，您将需要指定对XSetLocaleModifiers的修改，例如XSetLocaleModifiers("@im=none")，否则将不会生成额外的事件.
Finally, as mentioned in the comments, with recent versions of X11 you will need to specify a modify to XSetLocaleModifiers such as XSetLocaleModifiers("@im=none"), otherwise the extra events won't be generated.
这是该代码的更正版本:
Here is a corrected version of the code:
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/Xresource.h>
#include <X11/Xlocale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(int argc, char ** argv)
{
int screen_num, width, height;
unsigned long background, border;
Window win;
XEvent ev;
Display *dpy;
XIM im;
XIC ic;
char *failed_arg;
XIMStyles *styles;
XIMStyle xim_requested_style;
/* First connect to the display server, as specified in the DISPLAY
environment variable. */
if (setlocale(LC_ALL, "") == NULL) {
return 9;
}
if (!XSupportsLocale()) {
return 10;
}
if (XSetLocaleModifiers("@im=none") == NULL) {
return 11;
}
dpy = XOpenDisplay(NULL);
if (!dpy) {
fprintf(stderr, "unable to connect to display");
return 7;
}
/* these are macros that pull useful data out of the display object */
/* we use these bits of info enough to want them in their own variables */
screen_num = DefaultScreen(dpy);
background = BlackPixel(dpy, screen_num);
border = WhitePixel(dpy, screen_num);
width = 400; /* start with a small window */
height = 200;
win = XCreateSimpleWindow(dpy, DefaultRootWindow(dpy), /* display, parent */
0,0, /* x, y: the window manager will place the window elsewhere */
width, height, /* width, height */
2, border, /* border width & colour, unless you have a window manager */
background); /* background colour */
/* tell the display server what kind of events we would like to see */
XSelectInput(dpy, win, ButtonPressMask|StructureNotifyMask|KeyPressMask|KeyReleaseMask);
/* okay, put the window on the screen, please */
XMapWindow(dpy, win);
im = XOpenIM(dpy, NULL, NULL, NULL);
if (im == NULL) {
fputs("Could not open input method\n", stdout);
return 2;
}
failed_arg = XGetIMValues(im, XNQueryInputStyle, &styles, NULL);
if (failed_arg != NULL) {
fputs("XIM Can't get styles\n", stdout);
return 3;
}
int i;
for (i = 0; i < styles->count_styles; i++) {
printf("style %d\n", (int)styles->supported_styles[i]);
}
ic = XCreateIC(im, XNInputStyle, XIMPreeditNothing | XIMStatusNothing, XNClientWindow, win, NULL);
if (ic == NULL) {
printf("Could not open IC\n");
return 4;
}
XSetICFocus(ic);
/* as each event that we asked about occurs, we respond. In this
* case we note if the window's shape changed, and exit if a button
* is pressed inside the window */
while(1) {
XNextEvent(dpy, &ev);
if (XFilterEvent(&ev, win))
continue;
switch(ev.type){
case MappingNotify:
XRefreshKeyboardMapping(&ev.xmapping);
break;
case KeyPress:
{
int count = 0;
KeySym keysym = 0;
char buf[20];
Status status = 0;
count = Xutf8LookupString(ic, (XKeyPressedEvent*)&ev, buf, 20, &keysym, &status);
printf("count: %d\n", count);
if (status==XBufferOverflow)
printf("BufferOverflow\n");
if (count)
printf("buffer: %.*s\n", count, buf);
if (status == XLookupKeySym || status == XLookupBoth) {
printf("status: %d\n", status);
}
printf("pressed KEY: %d\n", (int)keysym);
}
break;
case KeyRelease:
{
int count = 0;
KeySym keysym = 0;
char buf[20];
Status status = 0;
count = XLookupString((XKeyEvent*)&ev, buf, 20, &keysym, NULL);
if (count)
printf("in release buffer: %.*s\n", count, buf);
printf("released KEY: %d\n", (int)keysym);
}
break;
case ConfigureNotify:
if (width != ev.xconfigure.width
|| height != ev.xconfigure.height) {
width = ev.xconfigure.width;
height = ev.xconfigure.height;
printf("Size changed to: %d by %d", width, height);
}
break;
case ButtonPress:
XCloseDisplay(dpy);
return 0;
}
fflush(stdout);
}
}
这篇关于通过X11显示器获取UTF-8输入的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
