c ++上pdcurses的控制台菜单

Question

我想用pdcurses创建一个菜单，我无法在菜单中的第三项上移动的问题，我可以选择第一个或第二个，如何通过箭头移动到菜单中的第三个项目，通过“滚动菜单功能”，我们​​可以在菜单中导航。代码

#include <curses.h>
#include <stdlib.h>

#define ENTER 10
#define ESCAPE 27

void init_curses()
{
    initscr();
    start_color();
    init_pair(1,COLOR_WHITE,COLOR_BLUE);
    init_pair(2,COLOR_BLUE,COLOR_WHITE);
    init_pair(3,COLOR_RED,COLOR_WHITE);
    curs_set(0);
    noecho();
    keypad(stdscr,TRUE);
}

void draw_menubar(WINDOW *menubar)
{
    wbkgd(menubar,COLOR_PAIR(2));
    waddstr(menubar,"Menu1");
    wattron(menubar,COLOR_PAIR(3));
    waddstr(menubar,"(F1)");
    wattroff(menubar,COLOR_PAIR(3));
    wmove(menubar,0,20);
    waddstr(menubar,"Menu2");
    wattron(menubar,COLOR_PAIR(3));
    waddstr(menubar,"(F2)");
    wattroff(menubar,COLOR_PAIR(3));
    wmove(menubar,0,40);
    waddstr(menubar,"Menu3");
    wattron(menubar,COLOR_PAIR(3));
    waddstr(menubar,"(F3)");
    wattroff(menubar,COLOR_PAIR(3));
}

WINDOW **draw_menu(int start_col)
{
    int i;
    WINDOW **items;
    items=(WINDOW **)malloc(9*sizeof(WINDOW *));

    items[0]=newwin(10,19,1,start_col);
    wbkgd(items[0],COLOR_PAIR(2));
    box(items[0],ACS_VLINE,ACS_HLINE);
    items[1]=subwin(items[0],1,17,2,start_col+1);
    items[2]=subwin(items[0],1,17,3,start_col+1);
    items[3]=subwin(items[0],1,17,4,start_col+1);
    items[4]=subwin(items[0],1,17,5,start_col+1);
    items[5]=subwin(items[0],1,17,6,start_col+1);
    items[6]=subwin(items[0],1,17,7,start_col+1);
    items[7]=subwin(items[0],1,17,8,start_col+1);
    items[8]=subwin(items[0],1,17,9,start_col+1);
    for (i=1;i<9;i++)
        wprintw(items[i],"Item%d",i);
    wbkgd(items[1],COLOR_PAIR(1));
    wrefresh(items[0]);
    return items;
}

void delete_menu(WINDOW **items,int count)
{
    int i;
    for (i=0;i<count;i++)
    delwin(items[i]);
    free(items);
}

int scroll_menu(WINDOW **items,int count,int menu_start_col)
{
    int key;
    int selected=0;
    while (1) {
        key=getch();
        if (key==KEY_DOWN || key==KEY_UP) {
            wbkgd(items[selected+1],COLOR_PAIR(2));
            wnoutrefresh(items[selected+1]);
            if (key==KEY_DOWN) {
            selected=(selected+1) % count;
            } else {
                selected=(selected+count-1) % count;
            }
            wbkgd(items[selected+1],COLOR_PAIR(1));
            wnoutrefresh(items[selected+1]);
            doupdate();
        } else if (key==KEY_LEFT || key==KEY_RIGHT) {
            delete_menu(items,count+1);
            touchwin(stdscr);
            refresh();
            items=draw_menu(20-menu_start_col);//
            return scroll_menu(items,8,20-menu_start_col);
        } else if (key==ESCAPE) {
            return -1;
        } else if (key==ENTER) {
            return selected;
        }
    }
}

int main()
{
    int key;
    WINDOW *menubar,*messagebar;

    init_curses();

    bkgd(COLOR_PAIR(1));
    menubar=subwin(stdscr,1,80,0,0);
    messagebar=subwin(stdscr,1,79,23,1);
    draw_menubar(menubar);
    move(2,1);
    printw("Press F1 or F2 to open the menus. ");
    printw("ESC quits.");
    refresh();

    do {
        int selected_item;
        WINDOW **menu_items;
        key=getch();
        werase(messagebar);
        wrefresh(messagebar);
        if (key==KEY_F(1)) {
            menu_items=draw_menu(0);
            selected_item=scroll_menu(menu_items,8,0);
            delete_menu(menu_items,9);
            if (selected_item<0)
                wprintw(messagebar,"You haven't selected any item.");
            else
                wprintw(messagebar,
                "You have selected menu item %d.",selected_item+1);
            touchwin(stdscr);
            refresh();
        } else if (key==KEY_F(2)) {
            menu_items=draw_menu(20);
            selected_item=scroll_menu(menu_items,8,20);
            delete_menu(menu_items,9);
            if (selected_item<0)
                wprintw(messagebar,"You haven't selected any item.");
            else
                wprintw(messagebar,
                "You have selected menu item %d.",selected_item+1);
            touchwin(stdscr);
            refresh();
        }else if (key==KEY_F(3)) {
            menu_items=draw_menu(40);
            selected_item=scroll_menu(menu_items,8,40);
            delete_menu(menu_items,9);
            if (selected_item<0)
                wprintw(messagebar,"You haven't selected any item.");
            else
                wprintw(messagebar,
                "You have selected menu item %d.",selected_item+1);
            touchwin(stdscr);
            refresh();
        }
    } while (key!=ESCAPE);

    delwin(menubar);
    delwin(messagebar);
    endwin();
    return 0;
}