ask_for_hash_pair

# File ext/json/lib/json/editor.rb, line 831
      def ask_for_hash_pair(parent)
        key_input = type_input = value_input = nil

        dialog = Dialog.new("New (key, value) pair for Hash", nil, nil,
          [ Stock::OK, Dialog::RESPONSE_ACCEPT ],
          [ Stock::CANCEL, Dialog::RESPONSE_REJECT ]
        )
        dialog.width_request = 640

        hbox = HBox.new(false, 5)
        hbox.pack_start(Label.new("Key:"), false)
        hbox.pack_start(key_input = Entry.new)
        key_input.text = @key || ''
        dialog.vbox.pack_start(hbox, false)
        key_input.signal_connect(:activate) do
          if parent.any? { |c| c.content == key_input.text }
            toplevel.display_status('Key already exists in Hash!')
            key_input.text = ''
          else
            toplevel.display_status('Key has been changed.')
          end
        end

        hbox = HBox.new(false, 5)
        hbox.pack_start(Label.new("Type:"), false)
        hbox.pack_start(type_input = ComboBox.new(true))
        ALL_TYPES.each { |t| type_input.append_text(t) }
        type_input.active = @type || 0
        dialog.vbox.pack_start(hbox, false)

        type_input.signal_connect(:changed) do
          value_input.editable = false
          case ALL_TYPES[type_input.active]
          when 'Array', 'Hash'
            value_input.text = ''
          when 'TrueClass'
            value_input.text = 'true'
          when 'FalseClass'
            value_input.text = 'false'
          when 'NilClass'
            value_input.text = 'null'
          else
            value_input.text = ''
            value_input.editable = true
          end
        end

        hbox = HBox.new(false, 5)
        hbox.pack_start(Label.new("Value:"), false)
        hbox.pack_start(value_input = Entry.new)
        value_input.width_chars = 60
        value_input.text = @value || ''
        dialog.vbox.pack_start(hbox, false)

        dialog.signal_connect(:'key-press-event', &DEFAULT_DIALOG_KEY_PRESS_HANDLER)
        dialog.show_all
        self.focus = dialog
        dialog.run do |response| 
          if response == Dialog::RESPONSE_ACCEPT
            @key = key_input.text
            type = ALL_TYPES[@type = type_input.active]
            content = value_input.text
            return @key, type, content
          end
        end
        return
      ensure
        dialog.destroy
      end