Página oficial de documentación TK: http://www.tcl.tk/man/tcl8.5/contents.htm
Programa sacado de: http://www.tkdocs.com/tutorial/onepage.html
Es un programa que convierte de pies a metros usando de las librerías tk y tkextlib/tile
require 'tk'
require 'tkextlib/tile'
root = TkRoot.new {title "Pies a metros"}
content = Tk::Tile::Frame.new(root) {padding "3 3 12 12"}.grid( :sticky => 'nsew')
TkGrid.columnconfigure root, 0, :weight => 1; TkGrid.rowconfigure root, 0, :weight => 1
$feet = TkVariable.new; $meters = TkVariable.new
f = Tk::Tile::Entry.new(content) {width 7; textvariable $feet}.grid( :column => 2, :row => 1, :sticky => 'we' )
Tk::Tile::Label.new(content) {textvariable $meters}.grid( :column => 2, :row => 2, :sticky => 'we');
Tk::Tile::Button.new(content) {text 'Calcular'; command {calculate}}.grid( :column => 3, :row => 3, :sticky => 'w')
Tk::Tile::Label.new(content) {text 'Pies'}.grid( :column => 3, :row => 1, :sticky => 'w')
Tk::Tile::Label.new(content) {text 'Equivale a'}.grid( :column => 1, :row => 2, :sticky => 'e')
Tk::Tile::Label.new(content) {text 'Metros'}.grid( :column => 3, :row => 2, :sticky => 'w')
TkWinfo.children(content).each {|w| TkGrid.configure w, :padx => 5, :pady => 5}
f.focus
root.bind("Return") {calculate}
def calculate
begin
$meters.value = (0.3048*$feet*10000.0).round()/10000.0
rescue
$meters.value = ''
end
end
Tk.mainloop
