diff options
Diffstat (limited to 'lisp/button.el')
| -rw-r--r-- | lisp/button.el | 74 |
1 files changed, 66 insertions, 8 deletions
diff --git a/lisp/button.el b/lisp/button.el index b3afc4eca25..11317605cee 100644 --- a/lisp/button.el +++ b/lisp/button.el @@ -78,6 +78,10 @@ "Keymap useful for buffers containing buttons. Mode-specific keymaps may want to use this as their parent keymap.") +(define-minor-mode button-mode + "A minor mode for navigating to buttons with the TAB key." + :keymap button-buffer-map) + ;; Default properties for buttons. (put 'default-button 'face 'button) (put 'default-button 'mouse-face 'highlight) @@ -341,15 +345,14 @@ If the property `button-data' is present, it will later be used as the argument for the `action' callback function instead of the default argument, which is the button itself. -BEG can also be a string, in which case it is made into a button. +BEG can also be a string, in which case a copy of it is made into +a button and returned. Also see `insert-text-button'." (let ((object nil) (type-entry (or (plist-member properties 'type) (plist-member properties :type)))) - (when (stringp beg) - (setq object beg beg 0 end (length object))) ;; Disallow setting the `category' property directly. (when (plist-get properties 'category) (error "Button `category' property may not be set directly")) @@ -362,6 +365,10 @@ Also see `insert-text-button'." (setcar type-entry 'category) (setcar (cdr type-entry) (button-category-symbol (cadr type-entry)))) + (when (stringp beg) + (setq object (copy-sequence beg)) + (setq beg 0) + (setq end (length object))) ;; Now add all the text properties at once. (add-text-properties beg end ;; Each button should have a non-eq `button' @@ -461,18 +468,24 @@ see). POS defaults to point, except when `push-button' is invoked interactively as the result of a mouse-event, in which case, the mouse event is used. + If there's no button at POS, do nothing and return nil, otherwise -return t." +return t. + +To get a description of what function will called when pushing a +butting, use the `button-describe' command." (interactive (list (if (integerp last-command-event) (point) last-command-event))) (if (and (not (integerp pos)) (eventp pos)) ;; POS is a mouse event; switch to the proper window/buffer (let ((posn (event-start pos))) (with-current-buffer (window-buffer (posn-window posn)) - (if (posn-string posn) - ;; mode-line, header-line, or display string event. - (button-activate (posn-string posn) t) - (push-button (posn-point posn) t)))) + (let* ((str (posn-string posn)) + (str-button (and str (get-text-property (cdr str) 'button (car str))))) + (if str-button + ;; mode-line, header-line, or display string event. + (button-activate str t) + (push-button (posn-point posn) t))))) ;; POS is just normal position (let ((button (button-at (or pos (point))))) (when button @@ -550,6 +563,51 @@ Returns the button found." (interactive "p\nd\nd") (forward-button (- n) wrap display-message no-error)) +(defun button--describe (properties) + "Describe a button's PROPERTIES (an alist) in a *Help* buffer. +This is a helper function for `button-describe', in order to be possible to +use `help-setup-xref'. + +Each element of PROPERTIES should be of the form (PROPERTY . VALUE)." + (help-setup-xref (list #'button--describe properties) + (called-interactively-p 'interactive)) + (with-help-window (help-buffer) + (with-current-buffer (help-buffer) + (insert (format-message "This button's type is `%s'." + (alist-get 'type properties))) + (dolist (prop '(action mouse-action)) + (let ((name (symbol-name prop)) + (val (alist-get prop properties))) + (when (functionp val) + (insert "\n\n" + (propertize (capitalize name) 'face 'bold) + "\nThe " name " of this button is") + (if (symbolp val) + (progn + (insert (format-message " `%s',\nwhich is " val)) + (describe-function-1 val)) + (insert "\n") + (princ val)))))))) + +(defun button-describe (&optional button-or-pos) + "Display a buffer with information about the button at point. + +When called from Lisp, pass BUTTON-OR-POS as the button to describe, or a +buffer position where a button is present. If BUTTON-OR-POS is nil, the +button at point is the button to describe." + (interactive "d") + (let* ((button (cond ((integer-or-marker-p button-or-pos) + (button-at button-or-pos)) + ((null button-or-pos) (button-at (point))) + ((overlayp button-or-pos) button-or-pos))) + (props (and button + (mapcar (lambda (prop) + (cons prop (button-get button prop))) + '(type action mouse-action))))) + (when props + (button--describe props) + t))) + (provide 'button) ;;; button.el ends here |