如何在 python-curses 中制作滚动菜单

Question

有没有办法在 python-curses 中制作滚动菜单？ 我有一个从 sqlite3 中的查询中获得的记录列表，我必须将它们显示在一个框中，但它们超过了最大行数：我可以制作一个小菜单来显示它们，而不会使curses 崩溃吗？

Answer 1

此代码允许您从字符串列表的框中创建一个小菜单。
您还可以使用此代码从 sqlite 查询或 csv 文件中获取字符串列表。
要编辑菜单的最大行数，您只需编辑max_row 。
如果按 Enter，程序将打印选定的字符串值及其位置。

from __future__ import division  #You don't need this in Python3
import curses
from math import *



screen = curses.initscr()
curses.noecho()
curses.cbreak()
curses.start_color()
screen.keypad( 1 )
curses.init_pair(1,curses.COLOR_BLACK, curses.COLOR_CYAN)
highlightText = curses.color_pair( 1 )
normalText = curses.A_NORMAL
screen.border( 0 )
curses.curs_set( 0 )
max_row = 10 #max number of rows
box = curses.newwin( max_row + 2, 64, 1, 1 )
box.box()


strings = [ "a", "b", "c", "d", "e", "f", "g", "h", "i", "l", "m", "n" ] #list of strings
row_num = len( strings )

pages = int( ceil( row_num / max_row ) )
position = 1
page = 1
for i in range( 1, max_row + 1 ):
    if row_num == 0:
        box.addstr( 1, 1, "There aren't strings", highlightText )
    else:
        if (i == position):
            box.addstr( i, 2, str( i ) + " - " + strings[ i - 1 ], highlightText )
        else:
            box.addstr( i, 2, str( i ) + " - " + strings[ i - 1 ], normalText )
        if i == row_num:
            break

screen.refresh()
box.refresh()

x = screen.getch()
while x != 27:
    if x == curses.KEY_DOWN:
        if page == 1:
            if position < i:
                position = position + 1
            else:
                if pages > 1:
                    page = page + 1
                    position = 1 + ( max_row * ( page - 1 ) )
        elif page == pages:
            if position < row_num:
                position = position + 1
        else:
            if position < max_row + ( max_row * ( page - 1 ) ):
                position = position + 1
            else:
                page = page + 1
                position = 1 + ( max_row * ( page - 1 ) )
    if x == curses.KEY_UP:
        if page == 1:
            if position > 1:
                position = position - 1
        else:
            if position > ( 1 + ( max_row * ( page - 1 ) ) ):
                position = position - 1
            else:
                page = page - 1
                position = max_row + ( max_row * ( page - 1 ) )
    if x == curses.KEY_LEFT:
        if page > 1:
            page = page - 1
            position = 1 + ( max_row * ( page - 1 ) )

    if x == curses.KEY_RIGHT:
        if page < pages:
            page = page + 1
            position = ( 1 + ( max_row * ( page - 1 ) ) )
    if x == ord( "\n" ) and row_num != 0:
        screen.erase()
        screen.border( 0 )
        screen.addstr( 14, 3, "YOU HAVE PRESSED '" + strings[ position - 1 ] + "' ON POSITION " + str( position ) )

    box.erase()
    screen.border( 0 )
    box.border( 0 )

    for i in range( 1 + ( max_row * ( page - 1 ) ), max_row + 1 + ( max_row * ( page - 1 ) ) ):
        if row_num == 0:
            box.addstr( 1, 1, "There aren't strings",  highlightText )
        else:
            if ( i + ( max_row * ( page - 1 ) ) == position + ( max_row * ( page - 1 ) ) ):
                box.addstr( i - ( max_row * ( page - 1 ) ), 2, str( i ) + " - " + strings[ i - 1 ], highlightText )
            else:
                box.addstr( i - ( max_row * ( page - 1 ) ), 2, str( i ) + " - " + strings[ i - 1 ], normalText )
            if i == row_num:
                break



    screen.refresh()
    box.refresh()
    x = screen.getch()

curses.endwin()
exit()

Answer 2

要制作一个可以滚动大于一屏的文本的可滚动小部件，您需要使用curses.newpad

你可以在这里找到一个简单的例子： https : //stackoverflow.com/a/2523020/9205341
还有Python 3 / Python 2文档。

Answer 3

使用这个骨架，但添加 page-up / -down 以显示 10 组的条目。

在 python2 和 python3 中非常防撞！

---

#!/usr/bin/env python2
# -*- coding: UTF-8 -*-
#kate: syntax Python ;

# a skeleton menu with python2 & py3                  https://paste.cutelyst.org/

# https://0bin.net/paste/yauebNkDNbwgZqwy#a2YfWpSTHh0RV-0Yfz3FIypudIU6oi4DWvV9EGXo1Pv

'''function 1 on F1 1 and NUM-1'''
def funkt1():
    return 1

def funkt2():
    return 2

def funkt3():
    return 3

def funkt4():
    return 4

def funkt5():
    return 5

def funkt6():
    return 6

def funkt7():
    return 7

def funkt8():
    return 8

def funkt9():
    return 9




import sys,os
import curses

global menuE
global e
global noofmes
global keychar
e       = 0
menuE   = 1   # active entry
noofmes = 10  # number of menu entries +1
keychar = " " # like 1 or 2 ...

class switch(object):
    value = None
    def __new__(class_, value):
        class_.value = value
        return True

def case(*args):
    return any((arg == switch.value for arg in args))


def draw_menu(stdscr):
    global menuE
    global e
    global noofmes
    global keychar
    k        = 0
    cursor_x = 0
    cursor_y = 0

    # Clear and refresh the screen for a blank canvas
    stdscr.clear()
    stdscr.refresh()

    # Start colors in curses
    curses.start_color()
    curses.init_pair(1, curses.COLOR_CYAN,  curses.COLOR_BLACK)
    curses.init_pair(2, curses.COLOR_RED,   curses.COLOR_BLACK)
    curses.init_pair(3, curses.COLOR_BLACK, curses.COLOR_WHITE)

    # Loop where k is the last character pressed
    while (k != ord('q')):

        # Initialization
        stdscr.clear()
        height, width = stdscr.getmaxyx()

        ki              = int(k)
        try:    keychar = chr(k)
        except: keychar = 0
        callfunc        = False


        while switch(k):
            if case(49, 265, 360): # allows keys   1  or  NUM-1  or  F1     to be  Entry1    for  0..9
                menuE = 1
                break
            if case(50, 266     ): # 258   mouse u
                menuE = 2
                break
            if case(51, 267, 338):
                menuE = 3
                break
            if case(52, 268     ): #260
                menuE = 4
                break
            if case(53, 269, 69):
                menuE = 5
                break
            if case(54, 270     ): #261
                menuE = 6
                break
            if case(55, 271, 262):
                menuE = 7
                break
            if case(56, 272     ): #259   mouse d
                menuE = 8
                break
            if case(57, 273, 339):
                menuE = 9
                break
            if case(10, 32 , 83 ):   # SPACE  ,   ENTER  ,   83 mouse middle
                callfunc = True
                break
            pass
            break

        if callfunc:
            if   menuE == 1: e = funkt1()
            elif menuE == 2: e = funkt2()
            elif menuE == 3: e = funkt3()
            elif menuE == 4: e = funkt4()
            elif menuE == 5: e = funkt5()
            elif menuE == 6: e = funkt6()
            elif menuE == 7: e = funkt7()
            elif menuE == 8: e = funkt8()
            elif menuE == 9: e = funkt9()


        if k == curses.KEY_DOWN:
            cursor_y = cursor_y + 1
            menuE = (menuE + 1) % noofmes


        elif k == curses.KEY_UP:
            cursor_y = cursor_y - 1
            menuE = (menuE - 1) % noofmes

        elif k == curses.KEY_RIGHT:
            cursor_x = cursor_x + 1

        elif k == curses.KEY_LEFT:
            cursor_x = cursor_x - 1


        cursor_x = max(0, cursor_x)
        cursor_x = min(width-1, cursor_x)

        cursor_y = max(0, cursor_y)
        cursor_y = min(height-1, cursor_y)

        # Declaration of strings
        title        = "Python2 , py3  menu demo with lib ´curses´ "[:width-1]
        subtitle     = "because py2 will never die!"[:width-1]
        keystr       = str(e) + " <-- funkt  " + "Last key pressed: {}".format(k)[:width-1]
        statusbarstr = "Press 'q' to exit | STATUS BAR | Pos: {}, {}".format(cursor_x, cursor_y)
        if k == 0:
            keystr = "No key press detected..."[:width-1]

        # Centering calculations
        start_x_title    = int((  width // 2) - (len(title)    // 2) - len(title)    % 2)
        start_x_subtitle = int((  width // 2) - (len(subtitle) // 2) - len(subtitle) % 2)
        start_x_keystr   = int((  width // 2) - (len(keystr)   // 2) - len(keystr)   % 2)
        start_y          = int(( height // 2) -                   2)

        # Rendering some text
        whstr = "Width: {}, Height: {}".format(width, height)
        stdscr.addstr(0, 0, whstr, curses.color_pair(1))

        # Render status bar
        stdscr.attron(curses.color_pair(3))
        stdscr.addstr(height-1,  0, statusbarstr)
        stdscr.addstr(height-1, len(statusbarstr), " " * (width - len(statusbarstr) - 1))
        stdscr.attroff(curses.color_pair(3))

        # Turning on attributes for title
        stdscr.attron(curses.color_pair(2))
        stdscr.attron(curses.A_BOLD)

        # Rendering title
        stdscr.addstr(start_y -6, start_x_title, title)


        # Turning off attributes for title
        stdscr.attroff(curses.color_pair(2))
        stdscr.attroff(curses.A_BOLD)

        # Print rest of text
        stdscr.addstr( start_y - 4, start_x_subtitle, subtitle)

        #stdscr.addstr(start_y - 3, (width // 2) - 2, '-' * 4)
        stdscr.addstr( start_y - 2, start_x_keystr, keystr)


        # menu
        stdscr.addstr(start_y + 0,  start_x_subtitle, "~~~  Menu  ~~~")


        if menuE == 1 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 1,  start_x_subtitle, "1 Entry1")
        if menuE == 2 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 2,  start_x_subtitle, "2 Entry2")
        if menuE == 3 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 3 , start_x_subtitle, "3 Entry3")
        if menuE == 4 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 4 , start_x_subtitle, "4 Entry4")
        if menuE == 5 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 5 , start_x_subtitle, "5 Entry5")
        if menuE == 6 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 6 , start_x_subtitle, "6 Entry6")
        if menuE == 7 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 7 , start_x_subtitle, "7 Entry7")
        if menuE == 8 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 8 , start_x_subtitle, "8 Entry8")
        if menuE == 9 :
            stdscr.attron( curses.A_BOLD)
        else          :  stdscr.attroff(curses.A_BOLD)
        stdscr.addstr(start_y + 9 , start_x_subtitle, "9 Entry9")


        stdscr.move(cursor_y, cursor_x)

        # Refresh the screen
        stdscr.refresh()

        # Wait for next input
        k = stdscr.getch()

def main():
    curses.wrapper(draw_menu)

if __name__ == "__main__":
    main()

Answer 4

我用过https://github.com/wong2/pick

>>> title = 'Please choose your favorite programming language (press SPACE to mark, ENTER to continue): '
>>> options = ['Java', 'JavaScript', 'Python', 'PHP', 'C++', 'Erlang', 'Haskell']
>>> pick(options, title, multi_select=True, min_selection_count=1)

它创建了一个基于 ncurses 的选择器，占据整个终端窗口并让您选择多个选项（如果选项不适合页面，它将滚动选项）。 选择内容后，它会返回值及其索引：

[('Java', 0), ('C++', 4)]