Class

Summary

The class callbacks is used as a mixin by classes that provide callbacks.

Superclasses

capi-object

Subclasses

collection
item
menu-object

Initargs

:callback-type

The type of arguments for the callbacks.

:selection-callback

The callback for selecting an item.

:extend-callback

The callback for extending the selection.

:retract-callback

The callback for deselecting an item.

:action-callback

The callback for an action.

Accessors

callbacks-callback-type
callbacks-selection-callback
callbacks-extend-callback
callbacks-retract-callback
callbacks-action-callback

Description

Each callback function can be one of the following:

function

Call the function.

list

Apply the head of the list to the tail.

:redisplay-interface

Call redisplay-interface on the top-level interface.

:redisplay-menu-bar

Call redisplay-menu-bar on the top-level interface.

The slot value callback-type determines which arguments get passed to each of the callbacks. It can be any of the following values, and passes the corresponding data to the callback function:

:data

( item-data )

:data-interface

( item-data interface )

:interface-data

( interface item-data )

:item

( item )

:item-interface

( item interface )

:interface-item

( interface item )

:interface

( interface )

:full

( item-data item interface )

:none

()

nil

()

The item-data variable is the item's data if the item is of type item, otherwise it is the item itself, as for item. The item variable means the item itself. The interface is the interface of the element.

See also

choice
attach-interface-for-callback