Module: Amun::Helpers::Colors

Defined in:
lib/amun/helpers/colors.rb

Overview

Colors is responsible for registering new colors pairs (foreground and background) associate the pair with a name, then #use that pair for the next text printed on screen, also contains styles constants could be passed to #use to print bold or underline text for example

it’s important to understand that the number of pairs that coul’d be registered is limited to a number the current terminal specify, so registering, more color pairs than allowed will result in a RuntimeError.

color values could be taken from the xterm-256 color schema from here: upload.wikimedia.org/wikipedia/commons/1/15/Xterm_256color_chart.svg

Constant Summary collapse

ALTCHARSET = 
Curses::A_ALTCHARSET
COLOR = 
Curses::A_COLOR
LOW = 
Curses::A_LOW
STANDOUT = 
Curses::A_STANDOUT
DIM = 
Curses::A_DIM
NORMAL = 
Curses::A_NORMAL
TOP = 
Curses::A_TOP
Curses::A_BLINK
HORIZONTAL = 
Curses::A_HORIZONTAL
PROTECT = 
Curses::A_PROTECT
UNDERLINE = 
Curses::A_UNDERLINE
BOLD = 
Curses::A_BOLD
INVIS = 
Curses::A_INVIS
REVERSE = 
Curses::A_REVERSE
VERTICAL = 
Curses::A_VERTICAL
CHARTEXT = 
Curses::A_CHARTEXT
LEFT = 
Curses::A_LEFT
RIGHT = 
Curses::A_RIGHT
DEFAULT_COLOR = 
:default

Class Method Summary collapse

Class Method Details

print string in Curses window in the choosen color and style



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# File 'lib/amun/helpers/colors.rb', line 89

def print(curses_window, *strings)
  strings.each do |string|
    use(curses_window, string.color || DEFAULT_COLOR, string.style || NORMAL)
    curses_window << string
  end
end

.register(name, foreground, background) ⇒ Object

register or update a color pair with foreground and background colors, this method will raise RuntimeError if we exceeded the limit of color pairs allowed by the terminal

name(Symbol)

name of pair, could be used with the #use method

foreground(Number)

foreground color in current terminal color schema

background(Number)

background color in current terminal color schema



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# File 'lib/amun/helpers/colors.rb', line 55

def register(name, foreground, background)
  if !COLORS.key?(name) && COLORS.size >= Curses.color_pairs - 1
    raise ColorLimitExceeded, "Can't register color: #{name}, max: #{Curses.color_pairs}"
  end

  Curses.init_pair(COLORS[name], foreground, background)
end

.register_default(name, foreground, background) ⇒ Object

works like #register but doesn’t override your color if it’s already registered, this is a better method for any module to use to define colors #register should be used for redefining a color pair values



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# File 'lib/amun/helpers/colors.rb', line 72

def register_default(name, foreground, background)
  return if registered? name
  register(name, foreground, background)
end

.registered?(name) ⇒ Boolean

check if a color pair is registered or not, returns true if registered

Returns:

  • (Boolean) 


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# File 'lib/amun/helpers/colors.rb', line 64

def registered?(name)
  COLORS.key? name
end

.use(curses_window, name, type = NORMAL) ⇒ Object

use color pair for the next printed text

window(Curses Window)

that we need to change it’s colors

name(Symbol)

a color pair name registered before with #register

type(Colors::Constant)

a text style constant

defined in Colors, that manipulate the text style (Bold, Underline, Invert colors)



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# File 'lib/amun/helpers/colors.rb', line 83

def use(curses_window, name, type = NORMAL)
  index = COLORS.key?(name) ? COLORS[name] : 0
  curses_window.attron(Curses.color_pair(index) | type)
end