-;;; button.el --- Clickable buttons
+;;; button.el --- clickable buttons
;;
;; Copyright (C) 2001 Free Software Foundation, Inc.
;;
\f
;; Globals
-(defface button '((t :underline t))
+(defface button '((((type pc) (class color))
+ (:foreground "lightblue"))
+ (t :underline t))
"Default face used for buttons.")
;;;###autoload
(put 'default-button 'mouse-face 'highlight)
(put 'default-button 'keymap button-map)
(put 'default-button 'type 'button)
-(put 'default-button 'action 'button-nop)
+(put 'default-button 'action 'ignore)
(put 'default-button 'help-echo "mouse-2, RET: Push this button")
;; Make overlay buttons go away if their underlying text is deleted.
(put 'default-button 'evaporate t)
;; they inherit this.
(put 'default-button 'button t)
-;; This is the default button action.
-(defun button-nop (button)
- "Do nothing to BUTTON."
- nil)
+;; A `category-symbol' property for the default button type
+(put 'button 'button-category-symbol 'default-button)
\f
;; Button types (which can be used to hold default properties for buttons)
+;; Because button-type properties are inherited by buttons using the
+;; special `category' property (implemented by both overlays and
+;; text-properties), we need to store them on a symbol to which the
+;; `category' properties can point. Instead of using the symbol that's
+;; the name of each button-type, however, we use a separate symbol (with
+;; `-button' appended, and uninterned) to store the properties. This is
+;; to avoid name clashes.
+
+;; [this is an internal function]
+(defsubst button-category-symbol (type)
+ "Return the symbol used by button-type TYPE to store properties.
+Buttons inherit them by setting their `category' property to that symbol."
+ (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.
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
-creating the button)."
- ;; We use a different symbol than NAME (with `-button' appended, and
- ;; uninterned) to store the properties. This is to avoid name
- ;; clashes, since many very general properties may be include in
- ;; PROPERTIES.
- (let ((catsym (make-symbol (concat (symbol-name name) "-button"))))
+creating the button, using the :type keyword argument).
+
+In addition, the keyword argument :supertype may be used to specify a
+button-type from which NAME inherits its default property values
+\(however, the inheritance happens only when NAME is defined; subsequent
+changes to a supertype are not reflected in its subtypes)."
+ (let ((catsym (make-symbol (concat (symbol-name name) "-button")))
+ (super-catsym
+ (button-category-symbol
+ (or (plist-get properties 'supertype)
+ (plist-get properties :supertype)
+ 'button))))
;; Provide a link so that it's easy to find the real symbol.
(put name 'button-category-symbol catsym)
;; Initialize NAME's properties using the global defaults.
- (let ((default-props (symbol-plist 'default-button)))
+ (let ((default-props (symbol-plist super-catsym)))
(while default-props
(put catsym (pop default-props) (pop default-props))))
;; Add NAME as the `type' property, which will then be returned as
(put catsym 'type name)
;; Add the properties in PROPERTIES to the real symbol.
(while properties
- (put catsym (pop properties) (pop properties)))
+ (let ((prop (pop properties)))
+ (when (eq prop :supertype)
+ (setq prop 'supertype))
+ (put catsym prop (pop properties))))
+ ;; Make sure there's a `supertype' property
+ (unless (get catsym 'supertype)
+ (put catsym 'supertype 'button))
name))
-;; [this is an internal function]
-(defsubst button-category-symbol (type)
- "Return the symbol used by button-type TYPE to store properties.
-Buttons inherit them by setting their `category' property to that symbol."
- (or (get type 'button-category-symbol)
- (error "Unknown button type `%s'" type)))
-
(defun button-type-put (type prop val)
"Set the button-type TYPE's PROP property to VAL."
(put (button-category-symbol type) prop val))
"Get the property of button-type TYPE named PROP."
(get (button-category-symbol type) prop))
+(defun button-type-subtype-p (type supertype)
+ "Return t if button-type TYPE is a subtype of SUPERTYPE."
+ (or (eq type supertype)
+ (and type
+ (button-type-subtype-p (button-type-get type 'supertype)
+ supertype))))
+
\f
;; Button properties and other attributes
(defun button-put (button prop val)
"Set BUTTON's PROP property to VAL."
;; Treat some properties specially.
- (cond ((eq prop 'type)
+ (cond ((memq prop '(type :type))
;; We translate a `type' property a `category' property, since
;; that's what's actually used by overlays/text-properties for
;; inheriting properties.
(point-max))
prop val)))
-(defsubst button-activate (button)
- "Call BUTTON's action property."
- (funcall (button-get button 'action) button))
+(defsubst 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."
+ (funcall (or (and use-mouse-action (button-get button 'mouse-action))
+ (button-get button 'action))
+ button))
(defun button-label (button)
"Return BUTTON's text label."
(buffer-substring-no-properties (button-start button) (button-end button)))
+(defsubst button-type (button)
+ "Return BUTTON's button-type."
+ (button-get button 'type))
+
+(defun button-has-type-p (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))
+
\f
;; Creating overlay buttons
(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,
-specifying properties to add to the button. In particular, the `type'
-property may be used to specify a button-type from which to inherit
-other properties; see `define-button-type'.
+specifying properties to add to the button.
+In addition, the keyword argument :type may be used to specify a
+button-type from which to inherit other properties; see
+`define-button-type'.
Also see `make-text-button', `insert-button'."
(let ((overlay (make-overlay beg end nil t nil)))
(defun insert-button (label &rest properties)
"Insert a button with the label LABEL.
The remaining arguments form a sequence of PROPERTY VALUE pairs,
-specifying properties to add to the button. In particular, the `type'
-property may be used to specify a button-type from which to inherit
-other properties; see `define-button-type'.
+specifying properties to add to the button.
+In addition, the keyword argument :type may be used to specify a
+button-type from which to inherit other properties; see
+`define-button-type'.
Also see `insert-text-button', `make-button'."
(apply #'make-button
(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,
-specifying properties to add to the button. In particular, the `type'
-property may be used to specify a button-type from which to inherit
-other properties; see `define-button-type'.
+specifying properties to add to the button.
+In addition, the keyword argument :type may be used to specify a
+button-type from which to inherit other properties; see
+`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
;; Note that all the following code is basically equivalent to
;; `button-put', but we can do it much more efficiently since we
;; already have BEG and END.
- (cond ((eq prop 'type)
+ (cond ((memq prop '(type :type))
;; We translate a `type' property into a `category'
;; property, since that's what's actually used by
;; text-properties for inheritance.
(defun insert-text-button (label &rest properties)
"Insert a button with the label LABEL.
The remaining arguments form a sequence of PROPERTY VALUE pairs,
-specifying properties to add to the button. In particular, the `type'
-property may be used to specify a button-type from which to inherit
-other properties; see `define-button-type'.
+specifying properties to add to the button.
+In addition, the keyword argument :type may be used to specify a
+button-type from which to inherit other properties; see
+`define-button-type'.
This function is like `insert-button', except that the button is
actually part of the text instead of being a property of the buffer.
;; Must be a text-property button; return a marker pointing to it.
(copy-marker pos t))))
-(defun next-button (pos &optional n wrap count-current)
- "Return the Nth button after position POS in the current buffer.
-If N is negative, return the Nth button before POS.
-If no Nth button is found, return nil.
-If WRAP is non-nil, the search wraps around at the end of the buffer.
+(defun next-button (pos &optional count-current)
+ "Return the next button after position POS in the current buffer.
If COUNT-CURRENT is non-nil, count any button at POS in the search,
- instead of starting at the next button."
- (when (null n)
- (setq n 1))
- (if (< n 0)
- ;; reverse direction
- (previous-button pos (- n) wrap)
+instead of starting at the next button."
(unless count-current
;; Search for the next button boundary.
(setq pos (next-single-char-property-change pos 'button)))
- (let ((button (button-at pos)))
- (cond ((and button (>= n 2))
- ;; Found a button, but we want a different one; recurse.
- (next-button (button-start button) (1- n) wrap))
- (button
- ;; This is the button we want.
- button)
- ((= pos (point-max))
- ;; Failed to find a button going forwards, either wrap or
- ;; return failure.
- (and wrap (next-button (point-min) n nil t)))
- (t
+ (and (< pos (point-max))
+ (or (button-at pos)
;; We must have originally been on a button, and are now in
;; the inter-button space. Recurse to find a button.
- (next-button pos n wrap))))))
+ (next-button pos))))
-(defun previous-button (pos &optional n wrap count-current)
+(defun previous-button (pos &optional count-current)
"Return the Nth button before position POS in the current buffer.
-If N is negative, return the Nth button after POS.
-If no Nth button is found, return nil.
-If WRAP is non-nil, the search wraps around at the beginning of the buffer.
If COUNT-CURRENT is non-nil, count any button at POS in the search,
- instead of starting at the next button."
- (when (null n)
- (setq n 1))
- (if (< n 0)
- ;; reverse direction
- (next-button pos (- n) wrap)
- (unless count-current
- (setq pos (previous-single-char-property-change pos 'button)))
- (let ((button (and (> pos (point-min)) (button-at (1- pos)))))
- (cond ((and button (>= n 2))
- ;; Found a button, but we want a different one; recurse.
- (previous-button (button-start button) (1- n) wrap))
- (button
- ;; This is the button we want.
- button)
- ((= pos (point-min))
- ;; Failed to find a button going backwards, either wrap
- ;; or return failure.
- (and wrap (previous-button (point-max) n nil t)))
- (t
- ;; We must have originally been on a button, and are now in
- ;; the inter-button space. Recurse to find a button.
- (previous-button pos (max n 1) wrap))))))
+instead of starting at the next button."
+ (unless count-current
+ (setq pos (previous-single-char-property-change pos 'button)))
+ (and (> pos (point-min))
+ (or (button-at (1- pos))
+ ;; We must have originally been on a button, and are now in
+ ;; the inter-button space. Recurse to find a button.
+ (previous-button pos))))
\f
;; User commands
-(defun push-button (&optional pos)
+(defun push-button (&optional pos use-mouse-action)
"Perform the action specified by a button at location POS.
POS may be either a buffer position or a mouse-event.
+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.
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))))
+ (push-button (posn-point posn) t)))
;; POS is just normal position
(let ((button (button-at (or pos (point)))))
(if (not button)
nil
- (button-activate button)
+ (button-activate button use-mouse-action)
t))))
(defun forward-button (n &optional wrap display-message)
"Move to the Nth next button, or Nth previous button if N is negative.
+If N is 0, move to the start of any button at point.
If WRAP is non-nil, moving past either end of the buffer continues from the
other end.
If DISPLAY-MESSAGE is non-nil, the button's help-echo string is displayed.
+Any button with a non-nil `skip' property is skipped over.
Returns the button found."
(interactive "p\nd\nd")
- (let ((button (next-button (point) n wrap)))
+ (let (button)
+ (if (zerop n)
+ ;; Move to start of current button
+ (if (setq button (button-at (point)))
+ (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))))
+ (setq n (abs n))
+ (setq button t) ; just to start the loop
+ (while (and (> 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))
+ (unless (button-get button 'skip)
+ (setq n (1- n)))))))
(if (null button)
(error (if wrap "No buttons!" "No more buttons"))
- (goto-char (button-start button))
(let ((msg (and display-message (button-get button 'help-echo))))
(when msg
(message "%s" msg)))
(defun backward-button (n &optional wrap display-message)
"Move to the Nth previous button, or Nth next button if N is negative.
+If N is 0, move to the start of any button at point.
If WRAP is non-nil, moving past either end of the buffer continues from the
other end.
If DISPLAY-MESSAGE is non-nil, the button's help-echo string is displayed.
+Any button with a non-nil `skip' property is skipped over.
Returns the button found."
(interactive "p\nd\nd")
(forward-button (- n) wrap display-message))
HCoop / bpt / emacs.git / blobdiff