button%

Whenever a button is clicked by the user, the buttons's callback procedure is invoked. A callback procedure is provided as an initialization argument when each button is created.

• (make-object button% label parent callback style) -> button% object
      label : string or bitmap% object
      parent : frame%, dialog%, panel%, or pane% object
      callback : procedure of two arguments: a button% object and a control-event% object
      style = null : list of symbols in '(border)

  Creates a button with a string or bitmap label. If label is a bitmap, then the bitmap must be valid (see ok? in bitmap%) and not installed in a bitmap-dc% object; otherwise, an exn:application:mismatch exception is raised.

  If an ampersand (``&'') occurs in label (when label is a string), 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 effectively click the button 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).

  The callback procedure is called (with the event type 'button) whenever the user clicks the button.

  If style includes 'border, the button is drawn with a special border that indicates to the user that it is the default action button (see on-traverse-char).

  
  

• set-label

• accept-drop-files from window<%>
• client->screen from window<%>
• command from control<%>
• 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-label from window<%>
• get-parent from area<%>
• get-plain-label from window<%>
• 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 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 button%
  overrides set-label from window<%>
• show from window<%>
• stretchable-height from area<%>
• stretchable-width from area<%>
• vert-margin from subarea<%>