svn/view/modeline_element.rb

# modeline_element.rb: the class definition of Edmaru::ModeLineElement
#
# Copyright (C) 2007 Takashi Nakamoto
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301 USA.
#

module Edmaru

  #An instance of this element represents one element in a ModeLine bar.
  class ModeLineElement

    #Create a new ModeLine element.
    #
    #=== Arguments
    #_n_ :: The name of this element.
    #_w_ :: The width of this element excluding both of the left
    #border width and the right one.  A negative value for this
    #argument makes this element take variable width.
    #_l_ :: Left border width.
    #_r_ :: Right border width.
    #_t_ :: Default text.
    #
    #=== Return
    #An initialized element.
    def initialize(n, w = -1, l = 0, r = 0, t = "")
      @name = n
      @width = w
      @left_border = l
      @right_border = r
      @text = t
      @visible = false
    end

    #The name of this element.
    def name
      @name
    end

    #The actual width of this element including both the left border
    #width and the right one.
    def actual_width
      if @width < 0
        return @left_border + @text.size + @right_border
      else
        return @left_border + @width + @right_border
      end
    end

    #Set the text of this element.
    #
    #=== Warning
    #Do *NOT* use this assignment operator to change the surface text
    #of this element in the ModeLine that this element belongs
    #to. Call ModeLine#set_element_text to change the text.
    def text=(new_text)
      @text = new_text
    end

    #The text to be displayed.
    def text
      @text
    end

    #Set the visibility of this element.
    #
    #=== Warning
    #Do *NOT* use this assignment operator to show this element in the ModeLine
    #that this element belongs to. Call ModeLine#show_element or
    #ModeLine#hide_element to show or hide this element.
    def visible=(new_flag)
      @visible = new_flag
    end

    #Get the visibility of this element.
    def visible?
      @visible
    end

    #The surface string of this element for the ModeLine.
    #
    #=== Return
    #The surface string of this element.
    def surface
      #Return the empty string for any sake as long as the width is 0.
      if @width == 0
        return ""
      end

      ret = " " * @left_border
      if @width > 0
        #For the fixed width
        if @width <= @text.size
          #Cut the excessive tail characters.
          ret << @text[0, @width]
        else
          #Pad the text with space characters.
          ret << @text
          ret << " " * (@width - @text.size)
        end
      else
        #For the variable width.
        ret << @text
      end
      ret << " " * @right_border

      return ret
    end
  end
end