[ruby-talk:12814] Re: Tk Demo in Windows

"Ron Jeffries" <[e-mail]> wrote in message
news:[e-mail]...
> Hi Gang,
>
> I've been through the newsgroup and the web sites and could use some
> help with Tk in Windows. Does anyone have Conrad's widget demo running
> on Win 2000?
>
> When I run widget, I get a stack problem:
>
> from /cygdrive/c/ruby/lib/ruby/1.6/tk.rb:811:in `_invoke'
> ... 736 levels...
> from ./tkencoding.rb:25:in `_invoke'
> from /cygdrive/c/ruby/lib/ruby/1.6/tkafter.rb:14
> from C:\ruby\samples\tk\demos\widget:14:in `require'
> from C:\ruby\samples\tk\demos\widget:14
>
> This seems to be caused by requiring tkafter, if I remove that then I
> get the problem a little later, caused by tkencoding. If I remove
> that, I get
> command not found: cat ./button.rb
> which I suppose would be trivial to get around if I had a clue what
> "cat' is.
>
> So, anyway, is there a windows version of this stuff?
>
> Or am I on the wrong track entirely? What I'm trying to do, with Chet
> Hendrickson, is prepare for a demo we're doing at Software
> Development. We just need a fairly simple GUI, with a list box, a text
> box, some scrolling, simple menus, etc.
>
> I'm finding translating between the Perl/Tk and Ruby to be a bit hard
> for those first bites.
>
> Thanks,
>
> Ron
>
> Ronald E Jeffries
> http://www.XProgramming.com
> http://www.objectmentor.com

Hope this is what you are looking for, I translated the python example for
figure 2.5 in the book "Python and Tkinter  Programming" by John E. Grayson.
It is a direct translation avoiding any changes possible (save some minor
formatting).

It runs on my Windows 98 box.

I am using the install kit from Pragmatic Programmer's 1.6.2-3 (Custom
install, all features).

I commented out one line in the code since I did not know how to handle it
in Ruby and the menus (other than File->Exit) report a tcl script error
instead of doing nothing.

You should be able to run it from DOS using "ruby alltkwidgets.rb" (if you
saved it as alltkwidgets.rb that is). I also run it from inside Visual
SlickEdit without trouble (having set up VSE for Ruby).

First the code, then a file the code uses (the program looks for the support
file as matz.txt):

require "tk"

class AllTkWidgets

  def initialize(master)
    @frame = TkFrame.new(master)
    @frame.pack
  end

  mbar = TkFrame.new(@frame, "relief"=>"raised", "bd"=>2)
  mbar.pack("fill"=>"x")

  # Create File menu
  filebutton = TkMenubutton.new(mbar, "text"=>"File")
  filebutton.pack("side"=>"left")

  filemenu = TkMenu.new(filebutton, "tearoff"=>0)
  filebutton["menu"] = filemenu

  # Populate File menu
  filemenu.add("command", "label"=>"Exit", "command"=>"exit")

  # Create  object menu
  objectbutton = TkMenubutton.new(mbar, "text"=>"Object")
  objectbutton.pack("side"=>"left")

  objectmenu = TkMenu.new(objectbutton, "tearoff"=>0)
  objectbutton["menu"] = objectmenu

  # Populate object menu
  objectmenu.add("command", "label"=>"object", "command"=>"stub")

  # Create  edit menu
  editbutton = TkMenubutton.new(mbar, "text"=>"Edit")
  editbutton.pack("side"=>"left")

  editmenu = TkMenu.new(editbutton, "tearoff"=>0)
  editbutton["menu"] = editmenu

  # Populate edit menu
  editmenu.add("command", "label"=>"edit", "command"=>"stub")

  # Create  view menu
  viewbutton = TkMenubutton.new(mbar, "text"=>"View")
  viewbutton.pack("side"=>"left")

  viewmenu = TkMenu.new(viewbutton, "tearoff"=>0)
  viewbutton["menu"] = viewmenu

  # Populate view menu
  viewmenu.add("command", "label"=>"view", "command"=>"stub")

  # Create  tools menu
  toolsbutton = TkMenubutton.new(mbar, "text"=>"Tools")
  toolsbutton.pack("side"=>"left")

  toolsmenu = TkMenu.new(toolsbutton, "tearoff"=>0)
  toolsbutton["menu"] = toolsmenu

  # Populate tools menu
  toolsmenu.add("command", "label"=>"tools", "command"=>"stub")

  # Create  help menu
  helpbutton = TkMenubutton.new(mbar, "text"=>"Help")
  helpbutton.pack("side"=>"right")

  helpmenu = TkMenu.new(helpbutton, "tearoff"=>0)
  helpbutton["menu"] = helpmenu

  # Populate help menu
  helpmenu.add("command", "label"=>"help", "command"=>"stub")

  # Widgets
  iframe1 = TkFrame.new(@frame, "bd"=>2, "relief"=>"sunken")
  TkButton.new(iframe1, "text"=>"Button").pack("side"=>"left", "padx"=>5)
  TkCheckbutton.new(iframe1, "text"=>"CheckButton").pack("side"=>"left",
"padx"=>5)

  v=TkVariable.new
  TkRadiobutton.new(iframe1, "text"=>"Button", "variable"=>v,
    "value"=>3).pack("side"=>"right", "anchor"=>"w")
  TkRadiobutton.new(iframe1, "text"=>"Dio", "variable"=>v,
    "value"=>2).pack("side"=>"right", "anchor"=>"w")
  TkRadiobutton.new(iframe1, "text"=>"Ra", "variable"=>v,
    "value"=>1).pack("side"=>"right", "anchor"=>"w")
  iframe1.pack("expand"=>true, "fill"=>"x", "pady"=>10, "padx"=>5)

  iframe2 = TkFrame.new(@frame, "bd"=>2, "relief"=>"ridge")
  TkLabel.new(iframe2, "text"=>"Label widget:").pack("side"=>"left",
"padx"=>5)
  t = TkVariable.new
  e = TkEntry.new(iframe2, "textvariable"=>t,
"bg"=>"white").pack("side"=>"right", "padx"=>5)
  e.insert(0, "Entry widget")
  iframe2.pack("expand"=>true, "fill"=>"x", "pady"=>10, "padx"=>5)

  iframe3 = TkFrame.new(@frame, "bd"=>2, "relief"=>"groove")
  listbox = TkListbox.new(iframe3, "height"=>4)
  for line in ["Listbox Entry One","Entry Two","Entry Three","Entry Four"]
    listbox.insert("end", line)
  end
  listbox.pack("fill"=>"x", "padx"=>5)
  iframe3.pack("expand"=>true, "fill"=>"x", "pady"=>10, "padx"=>5)

  iframe4 = TkFrame.new(@frame, "bd"=>2, "relief"=>"sunken")
  text=TkText.new(iframe4, "height"=>10)
  fd = open("matz.txt")
  lines = fd.read
  fd.close
  text.insert("end", lines)
  text.pack("side"=>"left", "fill"=>"x", "padx"=>5)
  sb = TkScrollbar.new(iframe4, "orient"=>"vertical",
"command"=>proc{|*args| text.yview *args})
  sb.pack("side"=>"right", "fill"=>"y")
  text.yscrollcommand(proc {|first,last| sb.set(first,last)})
  iframe4.pack("expand"=>true, "fill"=>"x", "pady"=>10, "padx"=>5)

  iframe5 = TkFrame.new(@frame, "bd"=>2, "relief"=>"raised")
  TkScale.new(iframe5, "from"=>0.0, "to"=>50.0, "label"=>"Scale widget",
    "orient"=>"horizontal").pack("side"=>"left")
  c = TkCanvas.new(iframe5, "bg"=>"white", "width"=>340, "height"=>100)
  c.pack
  for i in (0..25)
    TkcOval.new(c, 5+(4*i),5+(3*i),(5*i)+60,(i)+60, "fill"=>"gray70")
  end
  TkcText.new(c, 260, 80, "text"=>"Canvas", "font"=>["verdana", 10, "bold"])
  iframe5.pack("expand"=>true, "fill"=>"x", "pady"=>10, "padx"=>5)

  iframen = TkFrame.new(@frame, "bd"=>2, "relief"=>"flat")
  TkMessage.new(iframen, "text"=>"This is a Message widget", "width"=>300,
    "relief"=>"sunken").pack("fill"=>"x", "padx"=>5)
  iframen.pack("expand"=>true, "fill"=>"x", "pady"=>10, "padx"=>5)

  def stub
  end

end

root = TkRoot.new
#root.option_add("*font", ["verdana", 10, "bold"])
all = AllTkWidgets.new(root)
root.title("Tk Widgets in Ruby")
root.mainloop

The matz.txt file:

What's Ruby

Ruby is the interpreted scripting language for quick and easy
object-oriented programming. It has many features to process text files and
to do system management tasks (as in Perl). It is simple, straight-forward,
extensible, and portable.

Oh, I need to mention, it's totally free, which means not only free of
charge, but also freedom to use, copy, modify, and distribute it.

Features of Ruby

Ruby has simple syntax, partially inspired by Eiffel and Ada.

Ruby has exception handling features, like Java or Python, to make it easy
to handle errors.

Ruby's operators are syntax sugar for the methods. You can redefine them
easily.

Ruby is a complete, full, pure object oriented language: OOL. This means all
data in Ruby is an object, not in the sense of Python or Perl, but in the
sense of Smalltalk: no exceptions. Example: In Ruby, the number 1 is an
instance of class Fixnum.

Ruby's OO is carefully designed to be both complete and open for
improvements. Example: Ruby has the ability to add methods to a class, or
even to an instance during runtime. So, if needed, an instance of one class
*can* behave differently from other instances of the same class.

Ruby features single inheritance only, *on purpose*. But Ruby knows the
concept of modules (called Categories in Objective-C). Modules are
collections of methods. Every class can import a module and so gets all its
methods for free. Some of us think that this is a much clearer way than
multiple inheritance, which is complex, and not used very often compared
with single inheritance (don't count C++ here, as it has often no other
choice due to strong type checking!).

Ruby features true closures. Not just unnamed function, but with present
variable bindings.

Ruby features blocks in its syntax (code surrounded by '{' ... '}' or 'do'
... 'end'). These blocks can be passed to methods, or converted into
closures.

Ruby features a true mark-and-sweep garbage collector. It works with all
Ruby objects. You don't have to care about maintaining reference counts in
extension libraries. This is better for your health. ;-)

Writing C extensions in Ruby is easier than in Perl or Python, due partly to
the garbage collector, and partly to the fine extension API. SWIG interface
is also available.

Integers in Ruby can (and should) be used without counting their internal
representation. There *are* small integers (instances of class Fixnum) and
large integers (Bignum), but you need not worry over which one is used
currently. If a value is small enough, an integer is a Fixnum, otherwise it
is a Bignum. Conversion occurs automatically.

Ruby needs no variable declarations. It uses simple naming conventions to
denote the scope of variables. Examples: simple 'var' = local variable,
'@var' = instance variable, '$var' = global variable. So it is also not
necessary to use a tiresome 'self.' prepended to every instance member.

Ruby can load extension libraries dynamically if an OS allows.

Ruby features OS independent threading. Thus, for all platforms on which
Ruby runs, you also have multithreading, regardless of if the OS supports it
or not, even on MS-DOS! ;-)

Ruby is highly portable: it is developed mostly on Linux, but works on many
types of UNIX, DOS, Windows 95/98/NT, Mac, BeOS, OS/2, etc.

The Creator of Ruby
Yukihiro Matsumoto, a.k.a Matz
[e-mail]