All Manuals > CAPI User Guide and Reference Manual > 21 CAPI Reference Entries

item Class

Summary

The class item groups together a title, some data and some callbacks into a single object for use in collections and choices.

Package

capi

Superclasses

callbacks
capi-object

Subclasses

menu-item
button
item-pinboard-object
popup-menu-button
toolbar-button

Initargs
:collection
The collection in which item is displayed.
:data
The data associated with the item.
:text
The text to appear in the item (or nil).
:print-function
If text is nil, this is called to print the data.
:selected
If t the item is selected.
Accessors

item-collection
item-data
item-text
item-print-function
item-selected

Description

An item can provide its own callbacks to override those specified in its enclosing collection, and can also provide some data to get passed to those callbacks.

An item is printed in the collection by print-collection-item. By default this returns a string using the item's text if specified, or else calls a print function on the item's data. The print-function will either be the one specified in the item, or else the print-function for its parent collection.

The selected slot in an item is non-nil if the item is currently selected. The accessor item-selected is provided to access and to set this value.

Examples
(defun main-callback (data interface)
  (capi:display-message "Main callback: ~S"
                        data))
(defun item-callback (data interface)
  (capi:display-message "Item callback: ~S"
                        data))
(capi:contain (make-instance
                'capi:list-panel
                :items (list
                         (make-instance
                          'capi:item
                          :text "Item"
                          :data '(some data)
                          :selection-callback 
                           'item-callback)
                         "Non-Item 1"
                         "Non-Item 2")
                :selection-callback 'main-callback))
See also

itemp
collection
choice
print-collection-item
9 Adding Toolbars


CAPI User Guide and Reference Manual (Macintosh version) - 01 Dec 2021 19:31:27