ruby-****@sourc*****
ruby-****@sourc*****
2009年 2月 7日 (土) 06:16:43 JST
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REMOTE_ADDR = 74.15.84.244
REMOTE_HOST =
URL = http://ruby-gnome2.sourceforge.jp/hiki.cgi?tut-gtk2-txtw-ttags
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@@ -124,3 +124,146 @@
window.add(hbox)
window.show_all
Gtk.main
+
+When you create a text tag, it is added to a Gtk::TextBuffer's tag table, an object that holds all the text buffer's tags. This happens behind the scene, when you execute Gtk::TextBuffer#create_tag command. This command has two arguments: ((*tag_name, properties.*)) The tag_name can be either a string or nil. If tag_name is nil, the tag is anonymous.
+
+--- create_tag(tag_name, properties)
+
+ Creates a tag and adds it to the tag table for buffer. If tag_name is non-nil, a tag called tag_name must not already exist in the tag table for this buffer.
+ * tag_name: name of the new tag, or nil
+ * properties: a hash of property names and values {name1 => value1, name2 => value2, ...}
+ * Returns: a new Gtk::TextTag
+
+The first argument ((*tag_name*)) is simple. It is an optional tag name. However, the second argument is more involved. It is a hash that may contain any number of name-value pairs representing tag properties. For example you may have a tag called "colors", and two properties "background" and "foreground" with their respective values:
+
+ buff.create_tag("colors",
+ { "foreground" => "#FFFFFF",
+ "background" => "#000000" }
+ )
+
+Once you created a tag with its properties you retrieve it from the text buffer's tag table by specifying its tag_name. At the same time you apply it to a segment or portion of the text bufer defined by star and end iterators. In the following snippet of code we create a an entry in tag table for the Gtk::TextBuffer object called buff. We create tag called "bold" and add for it a property name/value pair as hash {"weight" => Pango::WEIGHT_BOLD}. Subsequently (later in the program; in our case in a callback) we extract the property value pair for this tag:
+
+ buff.create_tag("bold", {"weight" => Pango::WEIGHT_BOLD})
+ ...
+ buff.apply_tag("bold", start_iter, end_iter)
+
+NOTE: in our example program we used a trick to obtain tag property names from button labels, where they are stored as Gtk::Stock items. If you need to store some new property such as a tag value in your widgets you could simply add it to the widget class as needed. For instance you could ezpand the Gtk::Button class to include a new property called ((*texttag*)). At the end of this session I will include a program that utilizes just mentioned skim.
+
+
+
+Following is the promised example program that modifies Gtk::Button class to include a new property to store a tag_name, used in Gtk::TextBuffer's tag table.
+
+((*texttags-button-texttag.rb*))
+
+ #!/usr/bin/env ruby
+ require 'gtk2'
+
+ # Retrieve the tag from the "tag" object data and apply it
+ # to the selection.
+ def format(b, txtvu)
+ s, e = txtvu.buffer.selection_bounds
+ txtvu.buffer.apply_tag(b.texttag, s, e)
+ end
+
+ # Apply the selected text size property as the tag.
+ def scale_changed(combo, txtvu)
+ return if combo.active == -1
+ s, e = txtvu.buffer.selection_bounds
+ txtvu.buffer.apply_tag(combo.active_text, s, e)
+ combo.active = -1
+ end
+
+ # Remove all of the tags from the selected text.
+ def clear_clicked(txtvu)
+ s, e = txtvu.buffer.selection_bounds
+ txtvu.buffer.remove_all_tags(s, e)
+ end
+
+ class TextToDouble
+ attr_accessor :str, :scale
+ def initialize(str, scale)
+ @str, @scale = str, scale
+ end
+ end
+
+ ts = Array.new
+ ts[0] = TextToDouble.new("Quarter Sized", 0.25)
+ ts[1] = TextToDouble.new("Double Extra Small", Pango::SCALE_XX_SMALL)
+ ts[2] = TextToDouble.new("Extra Small", Pango::SCALE_X_SMALL)
+ ts[3] = TextToDouble.new("Small", Pango::SCALE_SMALL)
+ ts[4] = TextToDouble.new("Medium", Pango::SCALE_MEDIUM)
+ ts[5] = TextToDouble.new("Large", Pango::SCALE_LARGE)
+ ts[6] = TextToDouble.new("Extra Large", Pango::SCALE_X_LARGE)
+ ts[7] = TextToDouble.new("Double Extra Large", Pango::SCALE_XX_LARGE)
+ ts[8] = TextToDouble.new("Double Sized", 2.0)
+
+ window = Gtk::Window.new(Gtk::Window::TOPLEVEL)
+ window.resizable = true
+ window.title = "Text Tags"
+ window.border_width = 10
+ window.signal_connect('delete_event') { Gtk.main_quit }
+ window.set_size_request(500, -1)
+
+ textview = Gtk::TextView.new
+
+ buffer = textview.buffer
+ buffer.create_tag("bold", {"weight" => Pango::WEIGHT_BOLD})
+ buffer.create_tag("italic", {"style" => Pango::STYLE_ITALIC})
+ buffer.create_tag("strikethrough", {"strikethrough" => true})
+ buffer.create_tag("underline", {"underline" => Pango::UNDERLINE_SINGLE})
+
+ bold = Gtk::Button.new(Gtk::Stock::BOLD);
+ italic = Gtk::Button.new(Gtk::Stock::ITALIC);
+ underline = Gtk::Button.new(Gtk::Stock::UNDERLINE);
+ strike = Gtk::Button.new(Gtk::Stock::STRIKETHROUGH);
+ clear = Gtk::Button.new(Gtk::Stock::CLEAR);
+
+ scale = Gtk::ComboBox.new # (text=true)
+ # scale.label = "eegg" # name, title ... ???
+
+ # Our little addition to the Button class, in order to
+ # save what usually is stored as label, however we use
+ # stock item rather than a label.
+ class Gtk::Button; attr_accessor :texttag; end
+
+ # Add the name of the text tag as a data parameter of the object.
+ bold.texttag = "bold"
+ italic.texttag = "italic"
+ underline.texttag = "underline"
+ strike.texttag = "strikethrough"
+
+ # Add choices to the GtkComboBox widget.
+ ts.each do |e|
+ scale.append_text(e.str)
+ buffer.create_tag(e.str, { "scale" => e.scale } )
+ end
+
+ # Connect each of the buttons and the combo box to the necessary signals.
+ bold.signal_connect("clicked") { |w| format(w, textview) }
+ italic.signal_connect("clicked") { |w| format(w, textview) }
+ underline.signal_connect("clicked") { |w| format(w, textview) }
+ strike.signal_connect("clicked") { |w| format(w, textview) }
+ scale.signal_connect("changed") { |w| scale_changed(w, textview) }
+ clear.signal_connect("clicked") { clear_clicked(textview) }
+
+ # Pack the widgets into a GtkVBox, GtkHBox, and then into the window. */
+ vbox = Gtk::VBox.new(true, 5)
+ vbox.pack_start(bold, false, false, 0)
+ vbox.pack_start(italic, false, false, 0)
+ vbox.pack_start(underline, false, false, 0)
+ vbox.pack_start(strike, false, false, 0)
+ vbox.pack_start(scale, false, false, 0)
+ vbox.pack_start(clear, false, false, 0)
+
+ scrolled_win = Gtk::ScrolledWindow.new
+ scrolled_win.border_width = 5
+ scrolled_win.add(textview)
+ scrolled_win.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_ALWAYS)
+
+ hbox = Gtk::HBox.new(false, 5)
+ hbox.pack_start(scrolled_win, true, true, 0)
+ hbox.pack_start(vbox, false, true, 0)
+
+ window.add(hbox)
+ window.show_all
+ Gtk.main