Page 327	Table of Contents	Index	Page 329
	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

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CHAPTER 30. GADGETS


30.4.1 The push-button Gadget

The push-button gadget provides press-to-activate switch behavior.

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

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

=> :show-as-default-p [Init Arg]
This is used to initialize the "show as default" property for the gadget, described below.

=> push-button-show-as-default-p push-button [Generic Function]
Returns the "show as default" property for the push button gadget. When true, the push button
will be drawn with a heavy border, which indicates that this button is the "default operation".

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

30.4.2 The toggle-button Gadget

The toggle-button gadget provides "on/off" switch behavior. This gadget typically appears as
a box that is optionally highlighted with a check-mark. If the check-mark is present, the gadget's
value is t, otherwise it is nil.

arm-callback will be invoked when the toggle button becomes armed (such as when the pointer
moves into it, or a pointer button is pressed over it). When the toggle 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 toggle button.

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

=> :indicator-type [Init Arg]
This is used to initialize the indicator type property for the gadget, described below.

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Page 327	Table of Contents	Index	Page 329
	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