【发布时间】：2017-08-06 20:18:17
【问题描述】：
我想学习 Ruby，所以我想我会尝试同时学习它和 Curses。我正在创建一个导航菜单，允许用户选择将运行系统命令的选项。
我已经创建了导航菜单，我可以使用箭头键循环浏览选项。
现在我正在尝试将 Enter 键读取为输入，并在按下 Enter 时运行系统命令。示例：
input = menu.getch
if input == ENTER
在
position = 3 if position < 0
position = 0 if position > 3
draw_menu(menu, position)
if position == 0
draw_info menu, 'You selected option 0'
input = menu.getch
if input == ENTER
menu.clear
menu.refresh
puts (system 'ls')
end
当按下 Enter 键时，系统命令确实有效（有点），但我遇到了一个问题，即如果刚刚选择或突出显示该选项，系统命令也会运行。我只希望它在按下 Enter 键时工作。
如果我把它改成
if input == 'k'
系统命令仅在按下 Enter 键时运行。突出显示或选择时不会运行。这就是我希望它工作的方式。
关于如何让 Enter 键与“k”键功能相同的任何想法？
这是我的代码。
require 'curses'
include Curses
# Top Lie
SCREEN_WIDTH = 90
HEADER_HEIGHT = 4
HEADER_WIDTH = SCREEN_WIDTH
# Bottom Line
SCREEN_WIDTH2 = 90
HEADER_HEIGHT2 = 1
HEADER_WIDTH2 = SCREEN_WIDTH2
Curses.init_screen
Curses.curs_set(0) # Invisible cursor
Curses.start_color
Curses.noecho # echo or noecho to display user input
Curses.nonl
Curses.raw
Curses.stdscr.nodelay = 1
Curses.init_pair(1, Curses::COLOR_WHITE, Curses::COLOR_BLUE)
Curses.init_pair(2, Curses::COLOR_WHITE, Curses::COLOR_BLUE)
begin
# Top Line
header_window = Curses::Window.new(HEADER_HEIGHT, HEADER_WIDTH, 0, 0) # (height, width, top, left)
header_window.color_set(1)
header_window << "Curses example".center(HEADER_WIDTH)
header_window.refresh
# Bottom Line
header2_window = Curses::Window.new(HEADER_HEIGHT, HEADER_WIDTH, 23, 0)
header2_window.color_set(2)
header2_window << "Curses example".center(HEADER_WIDTH)
header2_window.refresh
# Building a static window
def draw_menu(menu, active_index=nil)
["This is option 0.", "This is option 1.", "This is option 2.", "This is option 3."].each_with_index do |element, index|
# "w" for word array
# It's a shortcut for arrays
menu.setpos(index + 1, 1)
menu.attrset(index == active_index ? A_STANDOUT : A_NORMAL)
menu.addstr("#{index} - %-10s" % element) # %-Xs makes sure array words line up evenly if you place index after element
# you can change 17 to another number
end
menu.setpos(5, 1)
end
def draw_info(menu, text)
menu.setpos(6, 1) # sets the position of move up and down
# for example, menu.setpos(1, 10) moves to another
# location
menu.attrset(A_NORMAL)
menu.addstr text
end
position = 0
menu = Window.new(20, 70, 2, 2) # (height, width, top, left)
menu.keypad = true # enable keypad which allows arrow keys
#menu.box('|', '-')
draw_menu(menu, position)
while ch = menu.getch
stdscr.keypad = true
case ch
when KEY_UP, 'w'
#draw_info menu, 'move up'
position -= 1
when KEY_DOWN, 's'
#draw_info menu, 'move down'
position += 1
when 'x'
exit
end
position = 3 if position < 0
position = 0 if position > 3
draw_menu(menu, position)
if position == 0
draw_info menu, 'You selected option 0'
input = menu.getch
if input == 'k' # I want this to be ENTER
menu.clear
menu.refresh
puts (system 'ls') # This does not work well. I need to fix it.
end
elsif position == 1
draw_info menu, 'You selected option 1'
elsif position == 2
draw_info menu, 'You selected option 2'
else position == 3
draw_info menu, 'You selected option 3'
end
end
rescue => ex
Curses.close_screen
end
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