This is only meaningful for radio buttons or checkboxes in a list.
@end defun
+@defun widget-choose title items &optional event
+Prompt the user to choose an item from a list of options.
+
+@var{title} is the name of the list of options. @var{items} should be
+a menu, with its items in the simple format or in the extended format.
+@xref{Defining Menus,, Defining Menus, elisp, the Emacs Lisp Reference
+Manual}. Independently of the format, you don't have to provide a
+title for the menu, just pass the desired title in @var{title}. The
+optional @var{event} is an input event. If @var{event} is a mouse
+event and the number of elements in @var{items} is less than the user
+option @code{widget-menu-max-size}, then @code{widget-choose} uses a
+popup menu to prompt the user. Otherwise, @code{widget-choose} uses
+the minibuffer.
+
+When @var{items} is a keymap menu, the returned value is the symbol in
+the key vector, as in the argument of @code{define-key}
+(@pxref{Changing Key Bindings,,,elisp, the Emacs Lisp Reference
+Manual}). When @var{items} is a list whose selectable items are of
+the form (@var{name} . @var{value}) (i.e., the simplified format),
+then the return value is the @var{value} of the chosen element.
+@end defun
+
@node Widget Wishlist
@chapter Wishlist
@cindex todo
:group 'widgets
:type 'boolean)
+(defun widget--simplify-menu (extended)
+ "Convert the EXTENDED menu into a menu composed of simple menu items.
+
+Each item in the simplified menu is of the form (ITEM-STRING . REAL-BINDING),
+where both elements are taken from the EXTENDED MENU. ITEM-STRING is the
+correspondent ITEM-NAME in the menu-item entry:
+ (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST), and REAL-BINDING is
+the symbol in the key vector, as in `define-key'.
+ (See `(elisp)Defining Menus' for more information.)
+
+Only visible, enabled and meaningful menu items make their way into
+the returned simplified menu. That is:
+For the menu item to be visible, it has to either lack a :visible form in its
+item-property-list, or the :visible form has to evaluate to a non-nil value.
+For the menu item to be enabled, it has to either lack a :enabled form in its
+item-property-list, or the :enable form has to evaluate to a non-nil value.
+Additionally, if the menu item is a radio button, then its selected form has
+to evaluate to nil for the menu item to be meaningful."
+ (let (simplified)
+ (map-keymap (lambda (ev def)
+ (when (and (eq (nth 0 def) 'menu-item)
+ (nth 2 def)) ; Only menu-items with a real binding.
+ ;; Loop through the item-property-list, looking for
+ ;; :visible, :enable (or :active) and :button properties.
+ (let ((plist (nthcdr 3 def))
+ (enable t) ; Enabled by default.
+ (visible t) ; Visible by default.
+ selected keyword value)
+ (while (and plist (cdr plist)
+ (keywordp (setq keyword (car plist))))
+ (setq value (cadr plist))
+ (cond ((memq keyword '(:visible :included))
+ (setq visible value))
+ ((memq keyword '(:enable :active))
+ (setq enable value))
+ ((and (eq keyword :button)
+ (eq (car value) :radio))
+ (setq selected (cdr value))))
+ (setq plist (cddr plist)))
+ (when (and (eval visible)
+ (eval enable)
+ (or (not selected)
+ (not (eval selected))))
+ (push (cons (nth 1 def) ev) simplified)))))
+ extended)
+ (reverse simplified)))
+
(defun widget-choose (title items &optional event)
"Choose an item from a list.
First argument TITLE is the name of the list.
-Second argument ITEMS is a list whose members are either
+Second argument ITEMS should be a menu, either with simple item definitions,
+or with extended item definitions.
+When ITEMS has simple item definitions, it is a list whose members are either
(NAME . VALUE), to indicate selectable items, or just strings to
indicate unselectable items.
+
+When ITEMS is a menu that uses an extended format, then ITEMS should be a
+keymap, and each binding should look like this:
+ (menu-item ITEM-NAME REAL-BINDING . ITEM-PROPERTY-LIST)
+or like this: (menu-item ITEM-NAME) to indicate a non-selectable item.
+REAL-BINDING should be a symbol, and should not be a keymap, because submenus
+are not supported.
+
Optional third argument EVENT is an input event.
-The user is asked to choose between each NAME from the items alist,
-and the VALUE of the chosen element will be returned. If EVENT is a
-mouse event, and the number of elements in items is less than
+If EVENT is a mouse event, and the number of elements in items is less than
`widget-menu-max-size', a popup menu will be used, otherwise the
-minibuffer."
+minibuffer.
+
+The user is asked to choose between each NAME from ITEMS.
+If ITEMS has simple item definitions, then this function returns the VALUE of
+the chosen element. If ITEMS is a keymap, then the return value is the symbol
+in the key vector, as in the argument of `define-key'."
(cond ((and (< (length items) widget-menu-max-size)
event (display-popup-menus-p))
;; Mouse click.
- (x-popup-menu event
- (list title (cons "" items))))
+ (if (keymapp items)
+ ;; Modify the keymap prompt, and then restore the old one, if any.
+ (let ((prompt (keymap-prompt items)))
+ (unwind-protect
+ (progn
+ (setq items (delete prompt items))
+ (push title (cdr items))
+ ;; Return just the first element of the list of events.
+ (car (x-popup-menu event items)))
+ (setq items (delete title items))
+ (when prompt
+ (push prompt (cdr items)))))
+ (x-popup-menu event (list title (cons "" items)))))
((or widget-menu-minibuffer-flag
(> (length items) widget-menu-max-shortcuts))
+ (when (keymapp items)
+ (setq items (widget--simplify-menu items)))
;; Read the choice of name from the minibuffer.
(setq items (cl-remove-if 'stringp items))
(let ((val (completing-read (concat title ": ") items nil t)))
(setq val try))
(cdr (assoc val items))))))
(t
+ (when (keymapp items)
+ (setq items (widget--simplify-menu items)))
;; Construct a menu of the choices
;; and then use it for prompting for a single character.
(let* ((next-digit ?0)
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