-;;; button.el --- Clickable buttons
+;;; button.el --- clickable buttons
;;
-;; Copyright (C) 2001 Free Software Foundation, Inc.
+;; Copyright (C) 2001, 2005 Free Software Foundation, Inc.
;;
;; Author: Miles Bader <miles@gnu.org>
;; Keywords: extensions
\f
;; Globals
-(defface button '((t :underline t))
- "Default face used for buttons.")
+;; Use color for the MS-DOS port because it doesn't support underline.
+(defface button '((((type pc) (class color))
+ (:foreground "lightblue"))
+ (t :underline t))
+ "Default face used for buttons."
+ :group 'faces)
;;;###autoload
(defvar button-map
(put 'default-button 'mouse-face 'highlight)
(put 'default-button 'keymap button-map)
(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")
;; Make overlay buttons go away if their underlying text is deleted.
;; they inherit this.
(put 'default-button 'button t)
+;; 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.
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))
+ (let ((action (or (and use-mouse-action (button-get button 'mouse-action))
+ (button-get button 'action))))
+ (if (markerp action)
+ (save-selected-window
+ (select-window (display-buffer (marker-buffer action)))
+ (goto-char action)
+ (recenter 0))
+ (funcall 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
`make-text-button'.
Also see `insert-text-button'."
- (let (prop val)
- (while properties
- (setq prop (pop properties))
- (setq val (pop properties))
- ;; 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)
- ;; We translate a `type' property into a `category'
- ;; property, since that's what's actually used by
- ;; text-properties for inheritance.
- (setq prop 'category)
- (setq val (button-category-symbol val)))
- ((eq prop 'category)
- ;; Disallow setting the `category' property directly.
- (error "Button `category' property may not be set directly")))
- ;; Add the property.
- (put-text-property beg end prop val)))
+ (let ((type-entry
+ (or (plist-member properties 'type)
+ (plist-member properties :type))))
+ ;; Disallow setting the `category' property directly.
+ (when (plist-get properties 'category)
+ (error "Button `category' property may not be set directly"))
+ (if (null type-entry)
+ ;; The user didn't specify a `type' property, use the default.
+ (setq properties (cons 'category (cons 'default-button properties)))
+ ;; The user did specify a `type' property. Translate it into a
+ ;; `category' property, which is what's actually used by
+ ;; 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 properties)
;; Return something that can be used to get at the button.
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,
-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.
(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
+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.
+the normal action is used instead. The action may be either a
+function to call or a marker to display.
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.
(provide 'button)
+;;; arch-tag: 5f2c7627-413b-4097-b282-630f89d9c5e9
;;; button.el ends here
HCoop / bpt / emacs.git / blobdiff