1#!/usr/bin/env ruby
2
3require "tk"
4
5TkMessage.new(:width=>360, :text=><<EOM).pack
6This sample shows how to use a binary sequence between Ruby and Tk. \
7This reads the image data from the file as the binary sequence.
8
9To treat the difference of encodings between on Ruby and on Tk seamlessly, \
10Ruby/Tk converts the encoding of string arguments automatically. \
11I think it is comfortable for users on almost all situations. \
12However, when treats a binary sequence, the convert process makes troubles.
13
14Tk::BinaryString class (subclass of Tk::EncodedString class) is the class \
15to avoid such troubles. Please see the source code of this sample. \
16A Tk::BinaryString instance is used to create the image for the center button.
17EOM
18
19ImgFile=[File.dirname(__FILE__), 'images','tcllogo.gif'].join(File::Separator)
20
21ph1 = TkPhotoImage.new(:file=>ImgFile)
22p ph1.configinfo
23
24b_str = Tk::BinaryString(IO.read(ImgFile))
25p [b_str, b_str.encoding]
26
27ph2 = TkPhotoImage.new(:data=>b_str)
28p ph2.configinfo
29p ph2.data(:grayscale=>true)
30
31ph3 = TkPhotoImage.new(:palette=>256)
32ph3.put(ph2.data)
33
34ph4 = TkPhotoImage.new()
35ph4.put(ph2.data(:grayscale=>true))
36
37#p [b_str.encoding, b_str.rb_encoding]
38
39f = TkFrame.new.pack
40TkButton.new(:parent=>f, :image=>ph1, :command=>proc{exit}).pack(:side=>:left)
41TkButton.new(:parent=>f, :image=>ph2, :command=>proc{exit}).pack(:side=>:left)
42TkButton.new(:parent=>f, :image=>ph3, :command=>proc{exit}).pack(:side=>:left)
43TkButton.new(:parent=>f, :image=>ph4, :command=>proc{exit}).pack(:side=>:left)
44
45Tk.mainloop
46