From: nagai@...
Date: 2002-01-25T12:21:04+09:00
Subject: Re: Tk interface with Ruby

Hi, 

From: Bhagavatheeswaran Mahadevan <BMahadevan@NIIT.com>
Subject: Tk interface with Ruby
Date: Wed, 23 Jan 2002 22:24:06 +0900
Message-ID: <C4F9FF4A4CD3D511880500025558B3A01D2216@BOM-SFP-MSG1>
> I had one  question on the Tk interface with Ruby ................How do u
> place the widgets one below the another.......do u have any sample code for
> that.........maybe using the pack or grid feature .........

Pack and Grid arrange widgets *WITHOUT* overlapping. 
If you want to make a widget overlapping other widgets, 
please use Place geometry manager. 

# Or use two geometory managers on one Frame widget. :-)

And to change stacking order of such widgets, 
use raise or lower method. 

The following is a sample script; TkLabelFrame composite widget class. 
(And a sample of TkComposite module.)
In it, I use place geometory manager to arrange the label text on 
the relief of Frame widget. 

------------------------------------------------
class TkLabelFrame < TkFrame
  include TkComposite

  # default frame pad
  Default_FramePad = 10

  def initialize_composite(keys = {})
    keys = keys.dup

    # generate frames
    @relief_frame = TkFrame.new(@frame, 'relief'=>'groove', 
                                'borderwidth'=>2)
    @widget_frame = TkFrame.new(@relief_frame)
    @path = @widget_frame.path

    # generate label
    @box_label = TkLabel.new(@frame)

    # pack and place
    @widget_frame.pack('expand'=>true, 'fill'=>'both')
    @relief_frame.pack('ipadx'=>0, 'ipady'=>0, 'expand'=>true,
                       'fill'=>'both')

    # delegate
    delegate('DEFAULT', @frame, @relief_frame, @widget_frame)
    delegate('background', @frame, @relief_frame, 
             @widget_frame, @box_label)
    delegate('text', @box_label)
    delegate('font', @box_label)
    delegate('borderwidth', @relief_frame)
    delegate('relief', @relief_frame)

    # textforeground
    if color = keys.delete('textforeground')
      textforeground(color)
    end

    # framepad
    framepad(keys.delete('framepad'){Default_FramePad})

    # set property
    configure keys unless keys.empty?
  end

  def textforeground(color)
    @box_label.foreground(color)
  end

  def framepad(size)
    @widget_frame.pack('padx'=>size, 'pady'=>size)
    @relief_frame.pack('padx'=>size, 'pady'=>size)
    @box_label.place('x'=>size*2, 'y'=>size, 'anchor'=>'w')
  end
end
------------------------------------------------

And the next is a sample of usage. 

------------------------------------------------
fb = TkLabelFrame.new(nil, 'text'=>'BOX',
                      'background'=>'white',
                      'textforeground'=>'red',
                      'framepad'=>5).pack('expand'=>true, 
                                          'fill'=>'both')
TkButton.new(fb, 'text'=>'XXX').pack('fill'=>'x')
TkButton.new(fb, 'text'=>'EXIT', 
             'command'=>proc{exit}).pack('fill'=>'x')
------------------------------------------------
-- 
                                  Hidetoshi NAGAI (nagai@ai.kyutech.ac.jp)