我正在使用带有Ranger文件管理器之类的UI用C编写ncurses文件管理器。 到目前为止，这是我的代码：
#include <stdio.h>
#include <dirent.h>
#include <curses.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <pwd.h>
/*
Creates a new window with dimensions `height` and `width` starting at `starty` and `startx`
*/
WINDOW *create_newwin(int height, int width, int starty, int startx)
{
WINDOW *local_win;
local_win = newwin(height, width, starty, startx);
return local_win;
}
/*
Returns number of files in `char* directory`
*/
int getNumberofFiles(char* directory)
{
int len=0;
DIR *pDir;
struct dirent *pDirent;
pDir = opendir (directory);
if (pDir == NULL) {
printf ("Cannot open directory '%s'\n", directory);
exit(0);
}
while ((pDirent = readdir(pDir)) != NULL) {
// Skip hidden files
if(pDirent->d_name[0] != '.' )
len++;
}
return len;
}
/*
Stores all the file names in `char* directory` to `char *target[]`
*/
void getFiles(char* directory, char* target[])
{
int i = 0;
DIR *pDir;
struct dirent *pDirent;
pDir = opendir (directory);
if (pDir == NULL) {
printf ("Cannot open directory '%s'\n", directory);
exit(0);
}
while ((pDirent = readdir(pDir)) != NULL) {
// Skip hidden files
if(pDirent->d_name[0] != '.')
target[i++] = strdup(pDirent->d_name);
}
closedir (pDir);
}
int main(int argc, char* argv[])
{
// To store number of files in directory
int len=0;
// Counter variable
int i = 0;
// Direcotry to be opened
char* dir;
// Get UID of user
uid_t uid = getuid();
// Get home directory of user from UID
struct passwd *info = getpwuid(uid);
// No Path is given in arguments
// Set Path as $HOME
if(argc == 1)
{
dir = info->pw_dir;
}
// Path is given in arguments
// Set Path as the argument
else if(argc == 2)
{
dir = argv[1];
// Relative Path Given
if(dir[0] != '/')
{
// Add path of $HOME before the Relative Path
char temp[250] = "";
strcat(temp,info->pw_dir);
strcat(temp,"/");
strcat(temp,dir);
dir = temp;
}
}
// Incorrect Useage
else
{
printf("Incorrect Useage\n");
exit(0);
}
// Get number of files in the home directory
len = getNumberofFiles(dir);
// ncurses initialization
initscr();
raw();
noecho();
curs_set(0);
// Shows current directory
WINDOW *current_win;
// Shows child directory preview
WINDOW *preview_win;
int startx, starty, midx, midy, maxx, maxy;
// Index of currently selected item in `char* directories`
int selection = 0;
char ch;
do
{
len = getNumberofFiles(dir);
char* directories[len];
getFiles(dir, directories);
getmaxyx(stdscr, maxy, maxx);
// Make the two windows side-by-side
current_win = create_newwin(maxy, maxx/2+3, 0, 0);
preview_win = create_newwin(maxy, maxx/2 -1, 0, maxx/2 + 1);
// Print all the elements and highlight the selection
for( i=0; i<len; i++ )
{
if(i==selection)
wattron(current_win, A_STANDOUT);
else
wattroff(current_win, A_STANDOUT);
wmove(current_win,i+1,2);
wprintw(current_win, "%s\n", directories[i]);
}
char* selected_file = directories[selection];
char next_dir[250] = "";
char prev_dir[250] = "";
char *p;
// Get path of parent directory
strcat(prev_dir, dir);
p = strrchr(dir,'/');
prev_dir[p-dir] = '\0';
// Parent directory is root
if(prev_dir[0] != '/')
prev_dir[0] = '/';
// Get path of child directory
strcat(next_dir, dir);
strcat(next_dir, "/");
strcat(next_dir, directories[selection]);
int len_preview = getNumberofFiles(next_dir);
char* next_directories[len_preview];
getFiles(next_dir, next_directories);
for( i=0; i<len_preview; i++ )
{
wmove(preview_win,i+1,2);
wprintw(preview_win, "%s\n", next_directories[i]);
}
wattroff(current_win, A_STANDOUT);
box(current_win,0,0);
box(preview_win,0,0);
wrefresh(current_win);
wrefresh(preview_win);
// Keybindings
switch( ch = getch() ) {
case 'k':
selection--;
selection = ( selection < 0 ) ? len-1 : selection;
break;
case 'j':
selection++;
selection = ( selection > len-1 ) ? 0 : selection;
break;
case 'l':
strcpy(dir, next_dir);
selection = 0;
break;
case 'h':
strcpy(dir, prev_dir);
selection = 0;
break;
case 'g':
selection = 0;
break;
case 'G':
selection = len-1;
break;
}
// Free Memory
for( i=0; i<len_preview; i++ )
{
free(next_directories[i]);
}
for( i=0; i<len; i++ )
{
free(directories[i]);
}
} while( ch != 'q');
endwin();
return 0;
}
基本上，有两个并排渲染的窗口。一个是current_win，它显示当前目录中的所有文件，另一个是preview_win，它显示所选目录的子目录中的所有文件。
问题是，当当前目录中有很多文件时，当选择超出窗口范围时，窗口将不会滚动。我试过了
scrollok(current_win, TRUE);，但它会自动滚动到右下角并保持这种状态。
如何使其起作用？
（也是出于某种原因，在打开编译的二进制文件后，直到按下某个键，shell仍为空白）
答案 0 :(得分：0)
使用在窗口中滚动非常简单。当您写完末尾时，它将在底部插入空白行。而已。顶部的线消失了吗？它消失了。没有保留在某些屏幕外缓冲区中。一去不复返。这不是某种交互式双向滚动。它不知道您的“选择”在哪里，也无法对这些信息做任何事情。
要进行反向滚动，可以使用scrollok。像向前滚动一样，它只是在顶部添加一个空白行。重绘该行中的信息是您的责任。
诅咒pad可能会更容易使用更高级别的界面。
创建一个足以容纳整个列表的垫，然后用wscrl绘制顶部。当选择内容移出可见区域时，请使用更新的坐标再次调用prefresh，以告诉它显示包括新选择内容的打击垫的一部分。
答案 1 :(得分：0)
在阅读示例时，该块存在问题：
for( i=0; i<len; i++ )
{
if(i==selection)
wattron(current_win, A_STANDOUT);
else
wattroff(current_win, A_STANDOUT);
wmove(current_win,i+1,2);
wprintw(current_win, "%s\n", directories[i]);
}
如果 len 值大于窗口中的行数，则 wmove 调用将失败-将光标留在 wprintw 调用将其放置。如果不启用scrollok，它将位于窗口的右下方。但这（启用了scrollok）仍然是 current_win 的最后一行（在这种情况下为左下）。如果您拨出wmove个电话并启用scrollok，则结果将比您预期的还要多。
preview_win 的循环中存在相同的问题。
最后一个问题问一个空白的屏幕：那是因为在这一块中
wrefresh(current_win);
wrefresh(preview_win);
// Keybindings
switch( ch = getch() ) {
getch 呼叫执行
wrefresh(stdscr);
将覆盖刚刚绘制的窗口。您可以将wgetch更改为
switch ( ch = wgetch(current_win) ) {
和 stdscr 不会碍事。