From: Hidetoshi NAGAI <nagai@...>
Date: 2008-02-06T03:55:09+09:00
Subject: Re: Ruby/Tk/Iwidgets tabnotebook (and scrollbar)

Probably the following is better. Sorry.

> #!/usr/bin/env ruby
> require 'tk'
> require 'tkextlib/iwidgets'
> 
> # Create the tabnotebook widget and pack it.
> tn = Tk::Iwidgets::Tabnotebook.new(:width=>300, :height=>100)
> tn.pack(:anchor=>:nw, :fill=>:both, :expand=>true,
>         :side=>:top, :padx=>10, :pady=>0)
> 
> # Add twenty pages to the tabnotebook
> 1.upto(20) { |t|
>     txt = 'Page ' + t.to_s
>     tn.add(:label => txt)
> }

# Command to control the tabset
class Tk::Iwidgets::Tabnotebook
  def show_tab(idx)
    if (prev = @tabset.index(idx) - 1) < 0
      @tabset.start = 0
      return
    end
    case cget(:tabpos)
    when 's', 'n'
      poskey = :left
      szkey = :width
    when 'e', 'w'
      poskey = :top
      szkey = :height
    end
    if (hd = @tabset.tabcget(idx, poskey)) < 0
      @tabset.start -= hd
    elsif hd + (sz = @tabset.tabcget(idx, szkey)) > (tabs_sz = @tabset[szkey])
      @tabset.start -= hd - tabs_sz + 2*(hd - @tabset.tabcget(prev, poskey)) - sz + 1
    end
  end
end

tn.component_widget('tabset').command{|idx|
  tn.view(idx)
  tn.show_tab(idx)
}

> button = TkButton.new(tn.child_site(0),:text =>'Go to Page 20').pack
> button.command {
>     tn.select(19)       # tn.view etc have the same problem
> }
> 
> # Select the first page of the tabnotebook.
> tn.select(0)
> 
> # Create the scrollbar
> # and the notebook together, then pack the scrollbar
> tn.xscrollbar(TkScrollbar.new).pack(:fill=>:x,
>                                     :expand=>true, :padx=>10)
> 
> Tk.mainloop

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