From: Hidetoshi NAGAI <nagai@...>
Date: 2005-12-07T11:40:38+09:00
Subject: Re: [tk] Equivalent to Perl's Tk::Tiler?

From: Forrest Chang <fkc_email-news@yahoo.com>
Subject: [tk] Equivalent to Perl's Tk::Tiler?
Date: Tue, 6 Dec 2005 02:17:33 +0900
Message-ID: <81lkyz79dm.fsf@yahoo.com>
>    I making arbitrarily large forms and in doing similar in Perl, I've
> used Tk::Tiler, a scrollable frame.  I'd just pack my various entries
> into the form, and set a max size, from which the form would
> automatically scroll if the contents were larger than the form size.
> 
>    I've found a scrollable canvas sample I could use, but worry about the 
> of resources it might take up.  Any pointers?

I don't know Perl's Tk::Tiler. Is it the one like the following?
---------------------------------------------------------------
#
#  scrframe.rb
#
require 'tk'

class Tk::ScrollFrame < TkFrame
  include TkComposite

  DEFAULT_WIDTH  = 200
  DEFAULT_HEIGHT = 200

  def initialize_composite(keys={})
    @frame.configure(:width=>DEFAULT_WIDTH, :height=>DEFAULT_HEIGHT)

    # create scrollbars
    @v_scroll = TkScrollbar.new(@frame, 'orient'=>'vertical')
    @h_scroll = TkScrollbar.new(@frame, 'orient'=>'horizontal')

    # create a canvas widget
    @canvas = TkCanvas.new(@frame)

    # allignment
    TkGrid.rowconfigure(@frame, 0, 'weight'=>1, 'minsize'=>0)
    TkGrid.columnconfigure(@frame, 0, 'weight'=>1, 'minsize'=>0)
    @canvas.grid('row'=>0, 'column'=>0, 'sticky'=>'news')
    @frame.grid_propagate(false)

    # assign scrollbars
    @canvas.xscrollbar(@h_scroll)
    @canvas.yscrollbar(@v_scroll)

    # scrollbars ON
    vscroll(keys.delete('vscroll'){true})
    hscroll(keys.delete('hscroll'){true})

    # create base frame
    @base = TkFrame.new(@canvas)

    # embed base frame
    @cwin = TkcWindow.new(@canvas, [0, 0], :window=>@base, :anchor=>'nw')
    @canvas.scrollregion(@cwin.bbox)

    # binding to reset scrollregion
    @base.bind('Configure'){ @canvas.scrollregion(@cwin.bbox) }

    # set default receiver of method calls
    @path = @base.path

    # please check the differences of the following definitions
    option_methods(
      :scrollbarwidth
    )

    # set receiver widgets for configure methods (with alias)
    delegate_alias('scrollbarrelief', 'relief', @h_scroll, @v_scroll)

    # set receiver widgets for configure methods
    delegate('DEFAULT', @base)
    delegate('background', @frame, @base, @canvas, @h_scroll, @v_scroll)
    delegate('width', @frame)
    delegate('height', @frame)
    delegate('activebackground', @h_scroll, @v_scroll)
    delegate('troughcolor', @h_scroll, @v_scroll)
    delegate('repeatdelay', @h_scroll, @v_scroll)
    delegate('repeatinterval', @h_scroll, @v_scroll)
    delegate('borderwidth', @frame)
    delegate('relief', @frame)

    # do configure
    configure keys unless keys.empty?
  end

  # forbid to change binding of @base frame
  def bind(*args)
    @frame.bind(*args)
  end
  def bind_append(*args)
    @frame.bind_append(*args)
  end
  def bind_remove(*args)
    @frame.bind_remove(*args)
  end
  def bindinfo(*args)
    @frame.bindinfo(*args)
  end

  # set width of scrollbar
  def scrollbarwidth(width = nil)
    if width
      @h_scroll.width(width)
      @v_scroll.width(width)
    else
      @h_scroll.width
    end
  end

  # vertical scrollbar : ON/OFF
  def vscroll(mode)
    st = TkGrid.info(@v_scroll)
    if mode && st.size == 0 then
      @v_scroll.grid('row'=>0, 'column'=>1, 'sticky'=>'ns')
    elsif !mode && st.size != 0 then
      @v_scroll.ungrid
    end
    self
  end

  # horizontal scrollbar : ON/OFF
  def hscroll(mode)
    st = TkGrid.info(@h_scroll)
    if mode && st.size == 0 then
      @h_scroll.grid('row'=>1, 'column'=>0, 'sticky'=>'ew')
    elsif !mode && st.size != 0 then
      @h_scroll.ungrid
    end
    self
  end
end

# test
if __FILE__ == $0
  f = Tk::ScrollFrame.new(:scrollbarwidth=>10, :width=>300, :height=>200)
  f.pack(:expand=>true, :fill=>:both)

  TkButton.new(f, :text=>'foo bar button', :command=>proc{puts 'foo bar'}).pack
  Tk.after(3000){TkText.new(f).pack(:expand=>true, :fill=>:both)}

  Tk.mainloop
end
---------------------------------------------------------------
-- 
Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)