diff options
Diffstat (limited to 'lisp/wid-edit.el')
| -rw-r--r-- | lisp/wid-edit.el | 89 |
1 files changed, 82 insertions, 7 deletions
diff --git a/lisp/wid-edit.el b/lisp/wid-edit.el index 0a2ddb0ea1d..6568cd2c8f1 100644 --- a/lisp/wid-edit.el +++ b/lisp/wid-edit.el @@ -203,27 +203,100 @@ nil means read a single character." :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))) @@ -233,6 +306,8 @@ minibuffer." (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) |