radio-box%

A radio-box% control allows the user to select one of number of mutually exclusive items. The items are displayed as a vertical column or horizontal row of labelled radio buttons. Unlike a list-control<%>, the set of items in a radio-box% cannot be changed dynamically.

Whenever the user changes the selected radio button, the radio box's callback procedure is invoked. A callback procedure is provided as an initialization argument when each radio box is created.

• (make-object radio-box% label choices parent callback style) -> radio-box% object
      label : string or #f
      choices : list of strings or bitmap% objects
      parent : frame%, dialog%, panel%, or pane% object
      callback : procedure of two arguments: a radio-box% object and a control-event% object
      style = '(vertical) : list of symbols in '(horizontal vertical)

  Creates a radio button set with string or bitmap labels. The choices list specifies the radio button labels; the list of choices must be homogenous, either all strings or all bitmaps.

  If an ampersand (``&'') occurs in label, it is specially parsed; under Windows and X, the character following an ampersand is underlined in the displayed control to indicate a keyboard mnemonic. (Under MacOS, mnemonic underlines are not shown.) The underlined mnemonic character must be a letter or a digit. The user can move the keyboard focus to the radio box by typing the mnemonic when the control's top-level-window contains the keyboard focus. The user must also hold down the Meta or Alt key if the keyboard focus is currently in a control that handles normal alphanumeric input. The ampersand itself is removed from label before it is displayed for the control; a double-ampersand in label is converted to a single ampersand (with no mnemonic underlining). Mnemonic keyboard events are handled by on-traverse-char (but not under MacOS).

  Each string in choices can also contain an ampersand, which creates a mnemonic for clicking the corresponding radio button. As for label, a double ampersand is converted to a single ampersand.

  If choices is a list of bitmaps, then the bitmaps must be valid (see ok? in bitmap%) and not installed in a bitmap-dc% object; otherwise, an exn:application:mismatch exception is raised.

  If label is a string, it is used as the label for the radio box. Otherwise, the radio box does not display its label.

  The callback procedure is called (with the event type 'radio-box) when the user changes the radio button selection.

  The style argument must include either 'vertical for a collection of radio buttons vertically arranged, or 'horizontal for a horizontal arrangement.

  
  

• enable
• get-item-label
• get-item-plain-label
• get-number
• get-selection
• is-enabled?
• set-selection

• accept-drop-files from window<%>
• client->screen from window<%>
• command from control<%>
• enable from radio-box%
  overrides enable from window<%>
• focus from window<%>
• get-client-size from window<%>
• get-cursor from window<%>
• get-graphical-min-size from area<%>
• get-height from window<%>
• get-item-label from radio-box%
• get-item-plain-label from radio-box%
• get-label from window<%>
• get-number from radio-box%
• get-parent from area<%>
• get-plain-label from window<%>
• get-selection from radio-box%
• get-size from window<%>
• get-top-level-window from area<%>
• get-width from window<%>
• get-x from window<%>
• get-y from window<%>
• has-focus? from window<%>
• horiz-margin from subarea<%>
• is-enabled? from radio-box%
  overrides is-enabled? from window<%>
• is-shown? from window<%>
• min-height from area<%>
• min-width from area<%>
• on-drop-file from window<%>
• on-focus from window<%>
• on-move from window<%>
• on-size from window<%>
• on-subwindow-char from window<%>
• on-subwindow-event from window<%>
• refresh from window<%>
• screen->client from window<%>
• set-cursor from window<%>
• set-label from window<%>
• set-selection from radio-box%
• show from window<%>
• stretchable-height from area<%>
• stretchable-width from area<%>
• vert-margin from subarea<%>