;;; button.el --- clickable buttons
;;
-;; Copyright (C) 2001, 2002, 2003, 2004, 2005,
-;; 2006, 2007 Free Software Foundation, Inc.
+;; Copyright (C) 2001-2013 Free Software Foundation, Inc.
;;
;; Author: Miles Bader <miles@gnu.org>
;; Keywords: extensions
+;; Package: emacs
;;
;; This file is part of GNU Emacs.
;;
-;; GNU Emacs is free software; you can redistribute it and/or modify
+;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 2, or (at your option)
-;; any later version.
-;;
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
-;;
+
;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs; see the file COPYING. If not, write to the
-;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
-;; Boston, MA 02110-1301, USA.
+;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;;
;; the button is represented by a marker or buffer-position pointing
;; somewhere in the button. In the latter case, no markers into the
;; buffer are retained, which is important for speed if there are are
-;; extremely large numbers of buttons.
+;; extremely large numbers of buttons. Note however that if there is
+;; an existing face text-property at the site of the button, the
+;; button face may not be visible. Using overlays avoids this.
;;
;; Using `define-button-type' to define default properties for buttons
-;; is not necessary, but it is is encouraged, since doing so makes the
+;; is not necessary, but it is encouraged, since doing so makes the
;; resulting code clearer and more efficient.
;;
;; Use color for the MS-DOS port because it doesn't support underline.
;; FIXME if MS-DOS correctly answers the (supports) question, it need
;; no longer be a special case.
-(defface button '((((type pc) (class color))
- (:foreground "lightblue"))
- (((supports :underline t)) :underline t)
- (t (:foreground "lightblue")))
+(defface button '((t :inherit link))
"Default face used for buttons."
:group 'basic-faces)
-;;;###autoload
(defvar button-map
(let ((map (make-sparse-keymap)))
- (define-key map "\r" 'push-button)
+ ;; The following definition needs to avoid using escape sequences that
+ ;; might get converted to ^M when building loaddefs.el
+ (define-key map [(control ?m)] 'push-button)
(define-key map [mouse-2] 'push-button)
+ ;; FIXME: You'd think that for keymaps coming from text-properties on the
+ ;; mode-line or header-line, the `mode-line' or `header-line' prefix
+ ;; shouldn't be necessary!
+ (define-key map [mode-line mouse-2] 'push-button)
+ (define-key map [header-line mouse-2] 'push-button)
map)
"Keymap used by buttons.")
-;;;###autoload
(defvar button-buffer-map
(let ((map (make-sparse-keymap)))
(define-key map [?\t] 'forward-button)
(put 'default-button 'type 'button)
;; action may be either a function to call, or a marker to go to
(put 'default-button 'action 'ignore)
-(put 'default-button 'help-echo "mouse-2, RET: Push this button")
+(put 'default-button 'help-echo (purecopy "mouse-2, RET: Push this button"))
;; Make overlay buttons go away if their underlying text is deleted.
(put 'default-button 'evaporate t)
;; Prevent insertions adjacent to the text-property buttons from
(or (get type 'button-category-symbol)
(error "Unknown button type `%s'" type)))
-;;;###autoload
(defun define-button-type (name &rest properties)
- "Define a `button type' called NAME.
+ "Define a `button type' called NAME (a symbol).
The remaining arguments form a sequence of PROPERTY VALUE pairs,
specifying properties to use as defaults for buttons with this type
\(a button's type may be set by giving it a `type' property when
(defun button-get (button prop)
"Get the property of button BUTTON named PROP."
- (if (overlayp button)
- (overlay-get button prop)
- ;; Must be a text-property button.
- (get-text-property button prop)))
+ (cond ((overlayp button)
+ (overlay-get button prop))
+ ((button--area-button-p button)
+ (get-text-property (cdr button)
+ prop (button--area-button-string button)))
+ (t ; Must be a text-property button.
+ (get-text-property button prop))))
(defun button-put (button prop val)
"Set BUTTON's PROP property to VAL."
;; Disallow updating the `category' property directly.
(error "Button `category' property may not be set directly")))
;; Add the property.
- (if (overlayp button)
- (overlay-put button prop val)
- ;; Must be a text-property button.
- (put-text-property
- (or (previous-single-property-change (1+ button) 'button)
- (point-min))
- (or (next-single-property-change button 'button)
- (point-max))
- prop val)))
-
-(defsubst button-activate (button &optional use-mouse-action)
+ (cond ((overlayp button)
+ (overlay-put button prop val))
+ ((button--area-button-p button)
+ (setq button (button--area-button-string button))
+ (put-text-property 0 (length button) prop val button))
+ (t ; Must be a text-property button.
+ (put-text-property
+ (or (previous-single-property-change (1+ button) 'button)
+ (point-min))
+ (or (next-single-property-change button 'button)
+ (point-max))
+ prop val))))
+
+(defun button-activate (button &optional use-mouse-action)
"Call BUTTON's action property.
If USE-MOUSE-ACTION is non-nil, invoke the button's mouse-action
instead of its normal action; if the button has no mouse-action,
-the normal action is used instead."
+the normal action is used instead.
+
+The action can either be a marker or a function. If it's a
+marker then goto it. Otherwise it it is a function then it is
+called with BUTTON as only argument. BUTTON is either an
+overlay, a buffer position, or (for buttons in the mode-line or
+header-line) a string."
(let ((action (or (and use-mouse-action (button-get button 'mouse-action))
(button-get button 'action))))
(if (markerp action)
(defun button-label (button)
"Return BUTTON's text label."
- (buffer-substring-no-properties (button-start button) (button-end button)))
+ (if (button--area-button-p button)
+ (substring-no-properties (button--area-button-string button))
+ (buffer-substring-no-properties (button-start button)
+ (button-end button))))
(defsubst button-type (button)
"Return BUTTON's button-type."
"Return t if BUTTON has button-type TYPE, or one of TYPE's subtypes."
(button-type-subtype-p (button-get button 'type) type))
+(defun button--area-button-p (b)
+ "Return non-nil if BUTTON is an area button.
+Such area buttons are used for buttons in the mode-line and header-line."
+ (stringp (car-safe b)))
+
+(defalias 'button--area-button-string #'car
+ "Return area button BUTTON's button-string.")
\f
;; Creating overlay buttons
-;;;###autoload
(defun make-button (beg end &rest properties)
"Make a button from BEG to END in the current buffer.
The remaining arguments form a sequence of PROPERTY VALUE pairs,
;; OVERLAY is the button, so return it
overlay))
-;;;###autoload
(defun insert-button (label &rest properties)
"Insert a button with the label LABEL.
The remaining arguments form a sequence of PROPERTY VALUE pairs,
\f
;; Creating text-property buttons
-;;;###autoload
(defun make-text-button (beg end &rest properties)
"Make a button from BEG to END in the current buffer.
The remaining arguments form a sequence of PROPERTY VALUE pairs,
`define-button-type'.
This function is like `make-button', except that the button is actually
-part of the text instead of being a property of the buffer. Creating
-large numbers of buttons can also be somewhat faster using
-`make-text-button'.
+part of the text instead of being a property of the buffer. That is,
+this function uses text properties, the other uses overlays.
+Creating large numbers of buttons can also be somewhat faster
+using `make-text-button'. Note, however, that if there is an existing
+face property at the site of the button, the button face may not be visible.
+You may want to use `make-button' in that case.
+
+BEG can also be a string, in which case it is made into a button.
Also see `insert-text-button'."
- (let ((type-entry
+ (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"))
;; text-properties for inheritance.
(setcar type-entry 'category)
(setcar (cdr type-entry)
- (button-category-symbol (car (cdr type-entry))))))
- ;; Now add all the text properties at once
- (add-text-properties beg end
- ;; Each button should have a non-eq `button'
- ;; property so that next-single-property-change can
- ;; detect boundaries reliably.
- (cons 'button (cons (list t) properties)))
- ;; Return something that can be used to get at the button.
- beg)
-
-;;;###autoload
+ (button-category-symbol (car (cdr type-entry)))))
+ ;; Now add all the text properties at once
+ (add-text-properties beg end
+ ;; Each button should have a non-eq `button'
+ ;; property so that next-single-property-change can
+ ;; detect boundaries reliably.
+ (cons 'button (cons (list t) properties))
+ object)
+ ;; Return something that can be used to get at the button.
+ (or object beg)))
+
(defun insert-text-button (label &rest properties)
"Insert a button with the label LABEL.
The remaining arguments form a sequence of PROPERTY VALUE pairs,
;; Finding buttons in a buffer
(defun button-at (pos)
- "Return the button at position POS in the current buffer, or nil."
+ "Return the button at position POS in the current buffer, or nil.
+If the button at POS is a text property button, the return value
+is a marker pointing to POS."
(let ((button (get-char-property pos 'button)))
(if (or (overlayp button) (null button))
button
USE-MOUSE-ACTION is non-nil, invoke the button's mouse-action
instead of its normal action; if the button has no mouse-action,
the normal action is used instead. The action may be either a
-function to call or a marker to display.
+function to call or a marker to display and is invoked using
+`button-activate' (which 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.
;; POS is a mouse event; switch to the proper window/buffer
(let ((posn (event-start pos)))
(with-current-buffer (window-buffer (posn-window posn))
- (push-button (posn-point posn) t)))
+ (if (posn-string posn)
+ ;; mode-line, header-line, or display string event.
+ (button-activate (posn-string posn) t)
+ (push-button (posn-point posn)) t)))
;; POS is just normal position
(let ((button (button-at (or pos (point)))))
- (if (not button)
- nil
+ (when button
(button-activate button use-mouse-action)
t))))
(goto-char (button-start button)))
;; Move to Nth next button
(let ((iterator (if (> n 0) #'next-button #'previous-button))
- (wrap-start (if (> n 0) (point-min) (point-max))))
+ (wrap-start (if (> n 0) (point-min) (point-max)))
+ opoint fail)
(setq n (abs n))
(setq button t) ; just to start the loop
- (while (and (> n 0) button)
+ (while (and (null fail) (> n 0) button)
(setq button (funcall iterator (point)))
(when (and (not button) wrap)
(setq button (funcall iterator wrap-start t)))
(when button
(goto-char (button-start button))
+ ;; Avoid looping forever (e.g., if all the buttons have
+ ;; the `skip' property).
+ (cond ((null opoint)
+ (setq opoint (point)))
+ ((= opoint (point))
+ (setq fail t)))
(unless (button-get button 'skip)
(setq n (1- n)))))))
(if (null button)
(provide 'button)
-;;; arch-tag: 5f2c7627-413b-4097-b282-630f89d9c5e9
;;; button.el ends here