Page 328	Table of Contents	Index	Page 330
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E

CHAPTER 30. GADGETS

=> toggle-button-indicator-type toggle-button [Generic Function]
Returns the indicator type for the toggle button. This will be either :one-of or :some-of. The
indicator type controls the appearance of the toggle button. For example, many toolkits present
a one-of-many choice differently from a some-of-many choice.

=> gadget-value (button toggle-button) [Method]
Returns true if the button is selected, otherwise returns false.

=> toggle-button-pane [Class]
The class that implements a portable toggle button; a subclass of toggle-button.

30.4.3 The menu-button Gadget

The menu-button gadget provides similar behavior to the toggle-button gadget, except that it
is intended for items in menus. The returned value is generally the item chosen from the menu.

arm-callback will be invoked when the menu button becomes armed (such as when the pointer
moves into it, or a pointer button is pressed over it). When the menu button is actually activated
(by releasing the pointer button over it), value-changed-callback will be invoked. Finally,
disarm-callback will be invoked after value-changed-callback, or when the pointer is moved
outside of the menu button.

=> menu-button [Class]
The class that implements an abstract menu button. It is a subclass of value-gadget and
labelled-gadget.

=> menu-button-pane [Class]
The class that implements a portable menu button; a subclass of menu-button.

30.4.4 The scroll-bar Gadget

The scroll-bar gadget corresponds to a scroll bar.

=> scroll-bar [Class]
The class that implements a scroll bar. This is a subclass of value-gadget, oriented-gadget,
and range-gadget-mixin.

=> :drag-callback [Init Arg]
=> :scroll-to-bottom-callback [Init Arg]
=> :scroll-to-top-callback [Init Arg]
=> :drag-down-line-callback [Init Arg]

Page 328	Table of Contents	Index	Page 330
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E