代码有点长，但这仅仅是因为我评论了所有内容，因此它非常容易阅读。基本上这是一个简单的基于文本的选择菜单，我正在研究。 你需要在Linux上并拥有一个C ++ 11编译器来正确运行它。这是代码（完整的功能示例，可以编译）：
#include <string>
#include <vector>
#include <iostream>
#include <unistd.h>
#include <sys/ioctl.h>
#include "raw_terminal.h" // for setting the terminal to raw mode
using namespace std;
/* Simple escape sequences to control the cursor and colors on the screen */
#define CLI_HIDE_CUR "\033[?25l"
#define CLI_SHOW_CUR "\033[?25h"
#define CLI_SAVE_CUR_POS "\033[s"
#define CLI_REST_CUR_POS "\033[u"
#define CLI_CLR_LAST_LINE "\033[A\033[2K"
#define CLI_MV_CUR_UP "\033[A"
#define CLI_MV_CUR_DN "\033[B"
#define CLI_DEFAULT_COLOR "\033[0m"
#define CLI_FGROUND_BLACK "\033[0;30m"
#define CLI_FGROUND_RED "\033[0;31m"
#define CLI_FGROUND_GREEN "\033[0;32m"
#define CLI_FGROUND_BROWN "\033[0;33m"
#define CLI_FGROUND_BLUE "\033[0;34m"
#define CLI_FGROUND_MAGENTA "\033[0;35m"
#define CLI_FGROUND_CYAN "\033[0;36m"
#define CLI_FGROUND_LIGHTGREY "\033[0;37m"
#define CLI_BOLD "\033[0;1m"
#define CLI_BGROUND_BLACK "\033[7;30m"
#define CLI_BGROUND_RED "\033[7;31m"
#define CLI_BGROUND_GREEN "\033[7;32m"
#define CLI_BGROUND_BROWN "\033[7;33m"
#define CLI_BGROUND_BLUE "\033[7;34m"
#define CLI_BGROUND_MAGENTA "\033[7;35m"
#define CLI_BGROUND_CYAN "\033[7;36m"
#define CLI_BGROUND_LIGHTGREY "\033[7;37m"
/* Centers a string in a 'width' character wide terminal
by appending spaces before and after the string */
auto centerText(string& text, int width) -> void;
/* Creates a selection menu on the screen */
auto selectionMenu(std::vector<std::string> items) -> int;
int main() {
std::vector<string> items;
items.push_back("Menu item one");
items.push_back("Menu item two");
items.push_back("Menu item three");
int selection = selectionMenu(items);
if (selection == -1) return 0;
cout << "You selected: " << items[selection] << endl;
cin.get();
return 0;
}
auto centerText(string& text, int width) -> void {
size_t len = text.length();
if (width <= len+1) return;
for (int i=0; i<(width - len)/2; i++) text.insert(text.begin(), ' ');
for (int i=0; i<(width - len)/2+len%2; i++) text.push_back(' ');
return;
}
auto selectionMenu(std::vector<std::string> items) -> int {
/* This stuff is required to get the width of the terminal
in order to center the text on the screen with centerText() */
struct winsize w;
ioctl(0, TIOCGWINSZ, &w);
/* Hide the cursor, initialize some variables */
cout << CLI_HIDE_CUR << CLI_DEFAULT_COLOR << endl;
int selection = 0, prevSelection, key;
/* Center the menu items on the screen */
for (const auto& s : items) centerText(s, w.ws_col);
/* Print out the menu items */
for (const auto& s : items) cout << s << endl;
/* Highlight the first item */
for (int i=0; i<items.size(); i++) cout << CLI_MV_CUR_UP;
cout << CLI_BGROUND_BROWN << items[selection] << endl;
/* Configure stuff so that we're able to retrieve raw keystrokes from stdin */
raw_terminal::setRawTerminal();
/* If the enter key is down, wait until it's released.
This prevents the user from accidentally selecting
an item after hitting enter in a previous menu. */
while (getchar() == '\n') { usleep(1000); }
/* Main loop */
while (1) {
key = getchar();
/* We're only interested in escape sequences (starting with '\033') */
if (key == '\033') {
/* If nothing comes after the escape character, then esc was pressed, so we quit. */
if (getchar() == -1) {
selection = -1;
goto MENU_END;
}
/* Get the next character in the received sequence */
key = getchar();
/* up arrow */
if (key == 65) {
prevSelection = selection;
selection--;
}
/* down arrow */
else if (key == 66) {
prevSelection = selection;
selection++;
}
/* If (first item - 1) or (last item + 1) is selected, loop around */
if (selection < 0) selection = items.size()+selection;
if (selection > items.size()-1) selection -= items.size();
/* Draw the previously selected line with the default colors */
cout << CLI_MV_CUR_UP << CLI_DEFAULT_COLOR << items[prevSelection] << endl;
cout << CLI_MV_CUR_UP;
/* Move the cursor to the new selection */
if (selection < prevSelection) for (int i=0; i<(prevSelection-selection); i++) cout << CLI_MV_CUR_UP;
if (selection > prevSelection) for (int i=0; i<(selection-prevSelection); i++) cout << CLI_MV_CUR_DN;
/* Draw the newly selected line with the highlighting color */
cout << CLI_BGROUND_BROWN << items[selection] << endl;
}
/* If the retrieved key is not an escape sequence, check whether it's the enter key.
If so, break the main loop and return the selected item's number. */
else if (key == '\n') break;
}
MENU_END:
cout << CLI_DEFAULT_COLOR;
/* Position the cursor below the menu to continue */
for (int i=0; i<items.size()-selection; i++) cout << CLI_MV_CUR_DN;
/* Unhide the cursor, and set the terminal back to normal mode */
cout << CLI_SHOW_CUR << endl;
raw_terminal::restoreTerminal();
/* Return selected item's number */
return selection;
}
这是raw_terminal.h：
#ifndef _RAW_TERMINAL_H_
#define _RAW_TERMINAL_H_
#include <cstring>
#include <iostream>
#include <termios.h>
class raw_terminal {
public:
static void setRawTerminal() {
/* set the terminal to raw mode */
if (isRaw) return;
tcgetattr(fileno(stdin), &orig_term_attr);
memcpy(&new_term_attr, &orig_term_attr, sizeof(struct termios));
new_term_attr.c_lflag &= ~(ECHO|ICANON);
new_term_attr.c_cc[VTIME] = 0;
new_term_attr.c_cc[VMIN] = 0;
tcsetattr(fileno(stdin), TCSANOW, &new_term_attr);
isRaw = true;
}
static void restoreTerminal() {
tcsetattr(fileno(stdin), TCSANOW, &orig_term_attr);
isRaw = false;
}
private:
static struct termios orig_term_attr;
static struct termios new_term_attr;
static bool isRaw;
};
struct termios raw_terminal::orig_term_attr;
struct termios raw_terminal::new_term_attr;
bool raw_terminal::isRaw = false;
#endif
如果你只使用向上/向下箭头，它就可以了。但是如果你向左或向右按（它不应该做任何事情）它会完全弄乱屏幕，重复菜单项和东西。 问题不在我猜的代码中，因为它完全忽略了左右键。我想这是按下那些东西的终端。那么我怎么能阻止这种情况发生呢？
任何帮助将不胜感激。谢谢！
答案 0 :(得分：1)
if (key == 65 || key == 68) // ...
if (key == 66 || key == 67) // ...
这样，左右键可以正常改变选择。 我原本想忽略这些键，只使用向上/向下，但这仍然比屏幕变得疯狂更好。