File name fix, for AUTHORS.
[emacs.git] / lisp / tree-widget.el
blob1e772449de6ae24daf4a97a923663493a275a80e
1 ;;; tree-widget.el --- Tree widget
3 ;; Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
5 ;; Author: David Ponce <david@dponce.com>
6 ;; Maintainer: David Ponce <david@dponce.com>
7 ;; Created: 16 Feb 2001
8 ;; Keywords: extensions
10 ;; This file is part of GNU Emacs
12 ;; GNU Emacs is free software: you can redistribute it and/or modify
13 ;; it under the terms of the GNU General Public License as published by
14 ;; the Free Software Foundation, either version 3 of the License, or
15 ;; (at your option) any later version.
17 ;; GNU Emacs is distributed in the hope that it will be useful,
18 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
19 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 ;; GNU General Public License for more details.
22 ;; You should have received a copy of the GNU General Public License
23 ;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
25 ;;; Commentary:
27 ;; This library provide a tree widget useful to display data
28 ;; structures organized in a hierarchical order.
30 ;; The following properties are specific to the tree widget:
32 ;; :open
33 ;; Set to non-nil to expand the tree. By default the tree is
34 ;; collapsed.
36 ;; :node
37 ;; Specify the widget used to represent the value of a tree node.
38 ;; By default this is an `item' widget which displays the
39 ;; tree-widget :tag property value if defined, or a string
40 ;; representation of the tree-widget value.
42 ;; :keep
43 ;; Specify a list of properties to keep when the tree is collapsed
44 ;; so they can be recovered when the tree is expanded. This
45 ;; property can be used in child widgets too.
47 ;; :expander (obsoletes :dynargs)
48 ;; Specify a function to be called to dynamically provide the
49 ;; tree's children in response to an expand request. This function
50 ;; will be passed the tree widget and must return a list of child
51 ;; widgets. Child widgets returned by the :expander function are
52 ;; stored in the :args property of the tree widget.
54 ;; :expander-p
55 ;; Specify a predicate which must return non-nil to indicate that
56 ;; the :expander function above has to be called. By default, to
57 ;; speed up successive expand requests, the :expander-p predicate
58 ;; return non-nil when the :args value is nil. So, by default, to
59 ;; refresh child values, it is necessary to set the :args property
60 ;; to nil, then redraw the tree.
62 ;; :open-icon (default `tree-widget-open-icon')
63 ;; :close-icon (default `tree-widget-close-icon')
64 ;; :empty-icon (default `tree-widget-empty-icon')
65 ;; :leaf-icon (default `tree-widget-leaf-icon')
66 ;; Those properties define the icon widgets associated to tree
67 ;; nodes. Icon widgets must derive from the `tree-widget-icon'
68 ;; widget. The :tag and :glyph-name property values are
69 ;; respectively used when drawing the text and graphic
70 ;; representation of the tree. The :tag value must be a string
71 ;; that represent a node icon, like "[+]" for example. The
72 ;; :glyph-name value must the name of an image found in the current
73 ;; theme, like "close" for example (see also the variable
74 ;; `tree-widget-theme').
76 ;; :guide (default `tree-widget-guide')
77 ;; :end-guide (default `tree-widget-end-guide')
78 ;; :no-guide (default `tree-widget-no-guide')
79 ;; :handle (default `tree-widget-handle')
80 ;; :no-handle (default `tree-widget-no-handle')
81 ;; Those properties define `item'-like widgets used to draw the
82 ;; tree guide lines. The :tag property value is used when drawing
83 ;; the text representation of the tree. The graphic look and feel
84 ;; is given by the images named "guide", "no-guide", "end-guide",
85 ;; "handle", and "no-handle" found in the current theme (see also
86 ;; the variable `tree-widget-theme').
88 ;; These are the default :tag values for icons, and guide lines:
90 ;; open-icon "[-]"
91 ;; close-icon "[+]"
92 ;; empty-icon "[X]"
93 ;; leaf-icon ""
94 ;; guide " |"
95 ;; no-guide " "
96 ;; end-guide " `"
97 ;; handle "-"
98 ;; no-handle " "
100 ;; The text representation of a tree looks like this:
102 ;; [-] 1 (open-icon :node)
103 ;; |-[+] 1.0 (guide+handle+close-icon :node)
104 ;; |-[X] 1.1 (guide+handle+empty-icon :node)
105 ;; `-[-] 1.2 (end-guide+handle+open-icon :node)
106 ;; |- 1.2.1 (no-guide+no-handle+guide+handle+leaf-icon leaf)
107 ;; `- 1.2.2 (no-guide+no-handle+end-guide+handle+leaf-icon leaf)
109 ;; By default, images will be used instead of strings to draw a
110 ;; nice-looking tree. See the `tree-widget-image-enable',
111 ;; `tree-widget-themes-directory', and `tree-widget-theme' options for
112 ;; more details.
114 ;;; History:
117 ;;; Code:
118 (eval-when-compile (require 'cl))
119 (require 'wid-edit)
121 ;;; Customization
123 (defgroup tree-widget nil
124 "Customization support for the Tree Widget library."
125 :version "22.1"
126 :group 'widgets)
128 (defcustom tree-widget-image-enable (if (fboundp 'display-images-p)
129 (display-images-p))
130 "Non-nil means that tree-widget will try to use images."
131 :type 'boolean
132 :group 'tree-widget)
134 (defvar tree-widget-themes-load-path
135 '(load-path
136 (let ((dir (if (fboundp 'locate-data-directory)
137 (locate-data-directory "tree-widget") ;; XEmacs
138 data-directory)))
139 (and dir (list dir (expand-file-name "images" dir))))
141 "List of locations in which to search for the themes sub-directory.
142 Each element is an expression that will be recursively evaluated until
143 it returns a single directory or a list of directories.
144 The default is to search in the `load-path' first, then in the
145 \"images\" sub directory in the data directory, then in the data
146 directory.
147 The data directory is the value of the variable `data-directory' on
148 Emacs, and what `(locate-data-directory \"tree-widget\")' returns on
149 XEmacs.")
151 (defcustom tree-widget-themes-directory "tree-widget"
152 "Name of the directory in which to look for an image theme.
153 When nil use the directory where the tree-widget library is located.
154 When it is a relative name, search in all occurrences of that sub
155 directory in the path specified by `tree-widget-themes-load-path'.
156 The default is to use the \"tree-widget\" relative name."
157 :type '(choice (const :tag "Default" "tree-widget")
158 (const :tag "Where is this library" nil)
159 (directory :format "%{%t%}:\n%v"))
160 :group 'tree-widget)
162 (defcustom tree-widget-theme nil
163 "Name of the theme in which to look for images.
164 This is a sub directory of the themes directory specified by the
165 `tree-widget-themes-directory' option.
166 The default theme is \"default\". When an image is not found in a
167 theme, it is searched in its parent theme.
169 A complete theme must at least contain images with these file names
170 with a supported extension (see also `tree-widget-image-formats'):
172 \"guide\"
173 A vertical guide line.
174 \"no-guide\"
175 An invisible vertical guide line.
176 \"end-guide\"
177 End of a vertical guide line.
178 \"handle\"
179 Horizontal guide line that joins the vertical guide line to an icon.
180 \"no-handle\"
181 An invisible handle.
183 Plus images whose name is given by the :glyph-name property of the
184 icon widgets used to draw the tree. By default these images are used:
186 \"open\"
187 Icon associated to an expanded tree.
188 \"close\"
189 Icon associated to a collapsed tree.
190 \"empty\"
191 Icon associated to an expanded tree with no child.
192 \"leaf\"
193 Icon associated to a leaf node."
194 :type '(choice (const :tag "Default" nil)
195 (string :tag "Name"))
196 :group 'tree-widget)
198 (defcustom tree-widget-image-properties-emacs
199 '(:ascent center :mask (heuristic t))
200 "Default properties of Emacs images."
201 :type 'plist
202 :group 'tree-widget)
204 (defcustom tree-widget-image-properties-xemacs
206 "Default properties of XEmacs images."
207 :type 'plist
208 :group 'tree-widget)
210 (defcustom tree-widget-space-width 0.5
211 "Amount of space between an icon image and a node widget.
212 Must be a valid space :width display property."
213 :group 'tree-widget
214 :type 'sexp)
216 ;;; Image support
218 (eval-and-compile ;; Emacs/XEmacs compatibility stuff
219 (cond
220 ;; XEmacs
221 ((featurep 'xemacs)
222 (defsubst tree-widget-use-image-p ()
223 "Return non-nil if image support is currently enabled."
224 (and tree-widget-image-enable
225 widget-glyph-enable
226 (console-on-window-system-p)))
227 (defsubst tree-widget-create-image (type file &optional props)
228 "Create an image of type TYPE from FILE, and return it.
229 Give the image the specified properties PROPS."
230 (apply 'make-glyph `([,type :file ,file ,@props])))
231 (defsubst tree-widget-image-formats ()
232 "Return the alist of image formats/file name extensions.
233 See also the option `widget-image-file-name-suffixes'."
234 (delq nil
235 (mapcar
236 #'(lambda (fmt)
237 (and (valid-image-instantiator-format-p (car fmt)) fmt))
238 widget-image-file-name-suffixes)))
240 ;; Emacs
242 (defsubst tree-widget-use-image-p ()
243 "Return non-nil if image support is currently enabled."
244 (and tree-widget-image-enable
245 widget-image-enable
246 (display-images-p)))
247 (defsubst tree-widget-create-image (type file &optional props)
248 "Create an image of type TYPE from FILE, and return it.
249 Give the image the specified properties PROPS."
250 (apply 'create-image `(,file ,type nil ,@props)))
251 (defsubst tree-widget-image-formats ()
252 "Return the alist of image formats/file name extensions.
253 See also the option `widget-image-conversion'."
254 (delq nil
255 (mapcar
256 #'(lambda (fmt)
257 (and (image-type-available-p (car fmt)) fmt))
258 widget-image-conversion)))
262 ;; Buffer local cache of theme data.
263 (defvar tree-widget--theme nil)
265 (defsubst tree-widget-theme-name ()
266 "Return the current theme name, or nil if no theme is active."
267 (and tree-widget--theme (car (aref tree-widget--theme 0))))
269 (defsubst tree-widget-set-parent-theme (name)
270 "Set to NAME the parent theme of the current theme.
271 The default parent theme is the \"default\" theme."
272 (unless (member name (aref tree-widget--theme 0))
273 (aset tree-widget--theme 0
274 (append (aref tree-widget--theme 0) (list name)))
275 ;; Load the theme setup from the first directory where the theme
276 ;; is found.
277 (catch 'found
278 (dolist (dir (tree-widget-themes-path))
279 (setq dir (expand-file-name name dir))
280 (when (file-accessible-directory-p dir)
281 (throw 'found
282 (load (expand-file-name
283 "tree-widget-theme-setup" dir) t)))))))
285 (defun tree-widget-set-theme (&optional name)
286 "In the current buffer, set the theme to use for images.
287 The current buffer must be where the tree widget is drawn.
288 Optional argument NAME is the name of the theme to use. It defaults
289 to the value of the variable `tree-widget-theme'.
290 Does nothing if NAME is already the current theme.
292 If there is a \"tree-widget-theme-setup\" library in the theme
293 directory, load it to setup a parent theme or the images properties.
294 Typically it should contain something like this:
296 (tree-widget-set-parent-theme \"my-parent-theme\")
297 (tree-widget-set-image-properties
298 (if (featurep 'xemacs)
299 '(:ascent center)
300 '(:ascent center :mask (heuristic t))
302 (or name (setq name (or tree-widget-theme "default")))
303 (unless (string-equal name (tree-widget-theme-name))
304 (set (make-local-variable 'tree-widget--theme)
305 (make-vector 4 nil))
306 (tree-widget-set-parent-theme name)
307 (tree-widget-set-parent-theme "default")))
309 (defun tree-widget--locate-sub-directory (name path &optional found)
310 "Locate all occurrences of the sub-directory NAME in PATH.
311 Return a list of absolute directory names in reverse order, or nil if
312 not found."
313 (condition-case err
314 (dolist (elt path)
315 (setq elt (eval elt))
316 (cond
317 ((stringp elt)
318 (and (file-accessible-directory-p
319 (setq elt (expand-file-name name elt)))
320 (push elt found)))
321 (elt
322 (setq found (tree-widget--locate-sub-directory
323 name (if (atom elt) (list elt) elt) found)))))
324 (error
325 (message "In tree-widget--locate-sub-directory: %s"
326 (error-message-string err))))
327 found)
329 (defun tree-widget-themes-path ()
330 "Return the path where to search for a theme.
331 It is specified in variable `tree-widget-themes-directory'.
332 Return a list of absolute directory names, or nil when no directory
333 has been found accessible."
334 (let ((path (aref tree-widget--theme 1)))
335 (cond
336 ;; No directory was found.
337 ((eq path 'void) nil)
338 ;; The list of directories is available in the cache.
339 (path)
340 ;; Use the directory where this library is located.
341 ((null tree-widget-themes-directory)
342 (when (setq path (locate-library "tree-widget"))
343 (setq path (file-name-directory path))
344 (setq path (and (file-accessible-directory-p path)
345 (list path)))
346 ;; Store the result in the cache for later use.
347 (aset tree-widget--theme 1 (or path 'void))
348 path))
349 ;; Check accessibility of absolute directory name.
350 ((file-name-absolute-p tree-widget-themes-directory)
351 (setq path (expand-file-name tree-widget-themes-directory))
352 (setq path (and (file-accessible-directory-p path)
353 (list path)))
354 ;; Store the result in the cache for later use.
355 (aset tree-widget--theme 1 (or path 'void))
356 path)
357 ;; Locate a sub-directory in `tree-widget-themes-load-path'.
359 (setq path (nreverse (tree-widget--locate-sub-directory
360 tree-widget-themes-directory
361 tree-widget-themes-load-path)))
362 ;; Store the result in the cache for later use.
363 (aset tree-widget--theme 1 (or path 'void))
364 path))))
366 (defconst tree-widget--cursors
367 ;; Pointer shapes when the mouse pointer is over inactive
368 ;; tree-widget images. This feature works since Emacs 22, and
369 ;; ignored on older versions, and XEmacs.
371 ("guide" . arrow)
372 ("no-guide" . arrow)
373 ("end-guide" . arrow)
374 ("handle" . arrow)
375 ("no-handle" . arrow)
378 (defsubst tree-widget-set-image-properties (props)
379 "In current theme, set images properties to PROPS.
380 Does nothing if images properties have already been set for that
381 theme."
382 (or (aref tree-widget--theme 2)
383 (aset tree-widget--theme 2 props)))
385 (defsubst tree-widget-image-properties (name)
386 "Return the properties of image NAME in current theme.
387 Default global properties are provided for respectively Emacs and
388 XEmacs in the variables `tree-widget-image-properties-emacs', and
389 `tree-widget-image-properties-xemacs'."
390 ;; Add the pointer shape
391 (cons :pointer
392 (cons (or (cdr (assoc name tree-widget--cursors)) 'hand)
393 (tree-widget-set-image-properties
394 (if (featurep 'xemacs)
395 tree-widget-image-properties-xemacs
396 tree-widget-image-properties-emacs)))))
398 (defun tree-widget-lookup-image (name)
399 "Look up in current theme for an image with NAME.
400 Search first in current theme, then in parent themes (see also the
401 function `tree-widget-set-parent-theme').
402 Return the first image found having a supported format, or nil if not
403 found."
404 (let (file)
405 (catch 'found
406 (dolist (default-directory (tree-widget-themes-path))
407 (dolist (dir (aref tree-widget--theme 0))
408 (dolist (fmt (tree-widget-image-formats))
409 (dolist (ext (cdr fmt))
410 (setq file (expand-file-name (concat name ext) dir))
411 (and (file-readable-p file)
412 (file-regular-p file)
413 (throw 'found
414 (tree-widget-create-image
415 (car fmt) file
416 (tree-widget-image-properties name))))))))
417 nil)))
419 (defun tree-widget-find-image (name)
420 "Find the image with NAME in current theme.
421 NAME is an image file name sans extension.
422 Return the image found, or nil if not found."
423 (when (tree-widget-use-image-p)
424 ;; Ensure there is an active theme.
425 (tree-widget-set-theme (tree-widget-theme-name))
426 (let ((image (assoc name (aref tree-widget--theme 3))))
427 ;; The image NAME is found in the cache.
428 (if image
429 (cdr image)
430 ;; Search the image in current, and default themes.
431 (prog1
432 (setq image (tree-widget-lookup-image name))
433 ;; Store image reference in the cache for later use.
434 (push (cons name image) (aref tree-widget--theme 3))))
437 ;;; Widgets
439 (defun tree-widget-button-click (event)
440 "Move to the position clicked on, and if it is a button, invoke it.
441 EVENT is the mouse event received."
442 (interactive "e")
443 (mouse-set-point event)
444 (let ((pos (widget-event-point event)))
445 (if (get-char-property pos 'button)
446 (widget-button-click event))))
448 (defvar tree-widget-button-keymap
449 (let ((km (make-sparse-keymap)))
450 (if (boundp 'widget-button-keymap)
451 ;; XEmacs
452 (progn
453 (set-keymap-parent km widget-button-keymap)
454 (define-key km [button1] 'tree-widget-button-click))
455 ;; Emacs
456 (set-keymap-parent km widget-keymap)
457 (define-key km [down-mouse-1] 'tree-widget-button-click))
459 "Keymap used inside node buttons.
460 Handle mouse button 1 click on buttons.")
462 (define-widget 'tree-widget-icon 'push-button
463 "Basic widget other tree-widget icons are derived from."
464 :format "%[%t%]"
465 :button-keymap tree-widget-button-keymap ; XEmacs
466 :keymap tree-widget-button-keymap ; Emacs
467 :create 'tree-widget-icon-create
468 :action 'tree-widget-icon-action
469 :help-echo 'tree-widget-icon-help-echo
472 (define-widget 'tree-widget-open-icon 'tree-widget-icon
473 "Icon for an expanded tree-widget node."
474 :tag "[-]"
475 :glyph-name "open"
478 (define-widget 'tree-widget-empty-icon 'tree-widget-icon
479 "Icon for an expanded tree-widget node with no child."
480 :tag "[X]"
481 :glyph-name "empty"
484 (define-widget 'tree-widget-close-icon 'tree-widget-icon
485 "Icon for a collapsed tree-widget node."
486 :tag "[+]"
487 :glyph-name "close"
490 (define-widget 'tree-widget-leaf-icon 'tree-widget-icon
491 "Icon for a tree-widget leaf node."
492 :tag ""
493 :glyph-name "leaf"
494 :button-face 'default
497 (define-widget 'tree-widget-guide 'item
498 "Vertical guide line."
499 :tag " |"
500 ;;:tag-glyph (tree-widget-find-image "guide")
501 :format "%t"
504 (define-widget 'tree-widget-end-guide 'item
505 "End of a vertical guide line."
506 :tag " `"
507 ;;:tag-glyph (tree-widget-find-image "end-guide")
508 :format "%t"
511 (define-widget 'tree-widget-no-guide 'item
512 "Invisible vertical guide line."
513 :tag " "
514 ;;:tag-glyph (tree-widget-find-image "no-guide")
515 :format "%t"
518 (define-widget 'tree-widget-handle 'item
519 "Horizontal guide line that joins a vertical guide line to a node."
520 :tag "-"
521 ;;:tag-glyph (tree-widget-find-image "handle")
522 :format "%t"
525 (define-widget 'tree-widget-no-handle 'item
526 "Invisible handle."
527 :tag " "
528 ;;:tag-glyph (tree-widget-find-image "no-handle")
529 :format "%t"
532 (define-widget 'tree-widget 'default
533 "Tree widget."
534 :format "%v"
535 :convert-widget 'tree-widget-convert-widget
536 :value-get 'widget-value-value-get
537 :value-delete 'widget-children-value-delete
538 :value-create 'tree-widget-value-create
539 :action 'tree-widget-action
540 :help-echo 'tree-widget-help-echo
541 :expander-p 'tree-widget-expander-p
542 :open-icon 'tree-widget-open-icon
543 :close-icon 'tree-widget-close-icon
544 :empty-icon 'tree-widget-empty-icon
545 :leaf-icon 'tree-widget-leaf-icon
546 :guide 'tree-widget-guide
547 :end-guide 'tree-widget-end-guide
548 :no-guide 'tree-widget-no-guide
549 :handle 'tree-widget-handle
550 :no-handle 'tree-widget-no-handle
553 ;;; Widget support functions
555 (defun tree-widget-p (widget)
556 "Return non-nil if WIDGET is a tree-widget."
557 (let ((type (widget-type widget)))
558 (while (and type (not (eq type 'tree-widget)))
559 (setq type (widget-type (get type 'widget-type))))
560 (eq type 'tree-widget)))
562 (defun tree-widget-node (widget)
563 "Return WIDGET's :node child widget.
564 If not found, setup an `item' widget as default.
565 Signal an error if the :node widget is a tree-widget.
566 WIDGET is, or derives from, a tree-widget."
567 (let ((node (widget-get widget :node)))
568 (if node
569 ;; Check that the :node widget is not a tree-widget.
570 (and (tree-widget-p node)
571 (error "Invalid tree-widget :node %S" node))
572 ;; Setup an item widget as default :node.
573 (setq node `(item :tag ,(or (widget-get widget :tag)
574 (widget-princ-to-string
575 (widget-value widget)))))
576 (widget-put widget :node node))
577 node))
579 (defun tree-widget-keep (arg widget)
580 "Save in ARG the WIDGET's properties specified by :keep."
581 (dolist (prop (widget-get widget :keep))
582 (widget-put arg prop (widget-get widget prop))))
584 (defun tree-widget-children-value-save (widget &optional args node)
585 "Save WIDGET children values.
586 WIDGET is, or derives from, a tree-widget.
587 Children properties and values are saved in ARGS if non-nil, else in
588 WIDGET's :args property value. Properties and values of the
589 WIDGET's :node sub-widget are saved in NODE if non-nil, else in
590 WIDGET's :node sub-widget."
591 (let ((args (cons (or node (widget-get widget :node))
592 (or args (widget-get widget :args))))
593 (children (widget-get widget :children))
594 arg child)
595 (while (and args children)
596 (setq arg (car args)
597 args (cdr args)
598 child (car children)
599 children (cdr children))
600 (if (tree-widget-p child)
601 ;;;; The child is a tree node.
602 (progn
603 ;; Backtrack :args and :node properties.
604 (widget-put arg :args (widget-get child :args))
605 (widget-put arg :node (widget-get child :node))
606 ;; Save :open property.
607 (widget-put arg :open (widget-get child :open))
608 ;; The node is open.
609 (when (widget-get child :open)
610 ;; Save the widget value.
611 (widget-put arg :value (widget-value child))
612 ;; Save properties specified in :keep.
613 (tree-widget-keep arg child)
614 ;; Save children.
615 (tree-widget-children-value-save
616 child (widget-get arg :args) (widget-get arg :node))))
617 ;;;; Another non tree node.
618 ;; Save the widget value.
619 (widget-put arg :value (widget-value child))
620 ;; Save properties specified in :keep.
621 (tree-widget-keep arg child)))))
623 ;;; Widget creation
625 (defvar tree-widget-before-create-icon-functions nil
626 "Hooks run before to create a tree-widget icon.
627 Each function is passed the icon widget not yet created.
628 The value of the icon widget :node property is a tree :node widget or
629 a leaf node widget, not yet created.
630 This hook can be used to dynamically change properties of the icon and
631 associated node widgets. For example, to dynamically change the look
632 and feel of the tree-widget by changing the values of the :tag
633 and :glyph-name properties of the icon widget.
634 This hook should be local in the buffer setup to display widgets.")
636 (defun tree-widget-icon-create (icon)
637 "Create the ICON widget."
638 (run-hook-with-args 'tree-widget-before-create-icon-functions icon)
639 (widget-put icon :tag-glyph
640 (tree-widget-find-image (widget-get icon :glyph-name)))
641 ;; Ensure there is at least one char to display the image.
642 (and (widget-get icon :tag-glyph)
643 (equal "" (or (widget-get icon :tag) ""))
644 (widget-put icon :tag " "))
645 (widget-default-create icon)
646 ;; Insert space between the icon and the node widget.
647 (insert-char ? 1)
648 (put-text-property
649 (1- (point)) (point)
650 'display (list 'space :width tree-widget-space-width)))
652 (defun tree-widget-convert-widget (widget)
653 "Convert :args as widget types in WIDGET."
654 (let ((tree (widget-types-convert-widget widget)))
655 ;; Compatibility
656 (widget-put tree :expander (or (widget-get tree :expander)
657 (widget-get tree :dynargs)))
658 tree))
660 (defun tree-widget-value-create (tree)
661 "Create the TREE tree-widget."
662 (let* ((node (tree-widget-node tree))
663 (flags (widget-get tree :tree-widget--guide-flags))
664 (indent (widget-get tree :indent))
665 ;; Setup widget's image support. Looking up for images, and
666 ;; setting widgets' :tag-glyph is done here, to allow to
667 ;; dynamically change the image theme.
668 (widget-image-enable (tree-widget-use-image-p)) ; Emacs
669 (widget-glyph-enable widget-image-enable) ; XEmacs
670 children buttons)
671 (and indent (not (widget-get tree :parent))
672 (insert-char ?\ indent))
673 (if (widget-get tree :open)
674 ;;;; Expanded node.
675 (let ((args (widget-get tree :args))
676 (guide (widget-get tree :guide))
677 (noguide (widget-get tree :no-guide))
678 (endguide (widget-get tree :end-guide))
679 (handle (widget-get tree :handle))
680 (nohandle (widget-get tree :no-handle))
681 (guidi (tree-widget-find-image "guide"))
682 (noguidi (tree-widget-find-image "no-guide"))
683 (endguidi (tree-widget-find-image "end-guide"))
684 (handli (tree-widget-find-image "handle"))
685 (nohandli (tree-widget-find-image "no-handle")))
686 ;; Request children at run time, when requested.
687 (when (and (widget-get tree :expander)
688 (widget-apply tree :expander-p))
689 (setq args (mapcar 'widget-convert
690 (widget-apply tree :expander)))
691 (widget-put tree :args args))
692 ;; Defer the node widget creation after icon creation.
693 (widget-put tree :node (widget-convert node))
694 ;; Create the icon widget for the expanded tree.
695 (push (widget-create-child-and-convert
696 tree (widget-get tree (if args :open-icon :empty-icon))
697 ;; Pass the node widget to child.
698 :node (widget-get tree :node))
699 buttons)
700 ;; Create the tree node widget.
701 (push (widget-create-child tree (widget-get tree :node))
702 children)
703 ;; Update the icon :node with the created node widget.
704 (widget-put (car buttons) :node (car children))
705 ;; Create the tree children.
706 (while args
707 (setq node (car args)
708 args (cdr args))
709 (and indent (insert-char ?\ indent))
710 ;; Insert guide lines elements from previous levels.
711 (dolist (f (reverse flags))
712 (widget-create-child-and-convert
713 tree (if f guide noguide)
714 :tag-glyph (if f guidi noguidi))
715 (widget-create-child-and-convert
716 tree nohandle :tag-glyph nohandli))
717 ;; Insert guide line element for this level.
718 (widget-create-child-and-convert
719 tree (if args guide endguide)
720 :tag-glyph (if args guidi endguidi))
721 ;; Insert the node handle line
722 (widget-create-child-and-convert
723 tree handle :tag-glyph handli)
724 (if (tree-widget-p node)
725 ;; Create a sub-tree node.
726 (push (widget-create-child-and-convert
727 tree node :tree-widget--guide-flags
728 (cons (if args t) flags))
729 children)
730 ;; Create the icon widget for a leaf node.
731 (push (widget-create-child-and-convert
732 tree (widget-get tree :leaf-icon)
733 ;; At this point the node widget isn't yet created.
734 :node (setq node (widget-convert
735 node :tree-widget--guide-flags
736 (cons (if args t) flags)))
737 :tree-widget--leaf-flag t)
738 buttons)
739 ;; Create the leaf node widget.
740 (push (widget-create-child tree node) children)
741 ;; Update the icon :node with the created node widget.
742 (widget-put (car buttons) :node (car children)))))
743 ;;;; Collapsed node.
744 ;; Defer the node widget creation after icon creation.
745 (widget-put tree :node (widget-convert node))
746 ;; Create the icon widget for the collapsed tree.
747 (push (widget-create-child-and-convert
748 tree (widget-get tree :close-icon)
749 ;; Pass the node widget to child.
750 :node (widget-get tree :node))
751 buttons)
752 ;; Create the tree node widget.
753 (push (widget-create-child tree (widget-get tree :node))
754 children)
755 ;; Update the icon :node with the created node widget.
756 (widget-put (car buttons) :node (car children)))
757 ;; Save widget children and buttons. The tree-widget :node child
758 ;; is the first element in :children.
759 (widget-put tree :children (nreverse children))
760 (widget-put tree :buttons buttons)))
762 ;;; Widget callbacks
764 (defsubst tree-widget-leaf-node-icon-p (icon)
765 "Return non-nil if ICON is a leaf node icon.
766 That is, if its :node property value is a leaf node widget."
767 (widget-get icon :tree-widget--leaf-flag))
769 (defun tree-widget-icon-action (icon &optional event)
770 "Handle the ICON widget :action.
771 If ICON :node is a leaf node it handles the :action. The tree-widget
772 parent of ICON handles the :action otherwise.
773 Pass the received EVENT to :action."
774 (let ((node (widget-get icon (if (tree-widget-leaf-node-icon-p icon)
775 :node :parent))))
776 (widget-apply node :action event)))
778 (defun tree-widget-icon-help-echo (icon)
779 "Return the help-echo string of ICON.
780 If ICON :node is a leaf node it handles the :help-echo. The tree-widget
781 parent of ICON handles the :help-echo otherwise."
782 (let* ((node (widget-get icon (if (tree-widget-leaf-node-icon-p icon)
783 :node :parent)))
784 (help-echo (widget-get node :help-echo)))
785 (if (functionp help-echo)
786 (funcall help-echo node)
787 help-echo)))
789 (defvar tree-widget-after-toggle-functions nil
790 "Hooks run after toggling a tree-widget expansion.
791 Each function is passed a tree-widget. If the value of the :open
792 property is non-nil the tree has been expanded, else collapsed.
793 This hook should be local in the buffer setup to display widgets.")
795 (defun tree-widget-action (tree &optional event)
796 "Handle the :action of the TREE tree-widget.
797 That is, toggle expansion of the TREE tree-widget.
798 Ignore the EVENT argument."
799 (let ((open (not (widget-get tree :open))))
800 (or open
801 ;; Before to collapse the node, save children values so next
802 ;; open can recover them.
803 (tree-widget-children-value-save tree))
804 (widget-put tree :open open)
805 (widget-value-set tree open)
806 (run-hook-with-args 'tree-widget-after-toggle-functions tree)))
808 (defun tree-widget-help-echo (tree)
809 "Return the help-echo string of the TREE tree-widget."
810 (if (widget-get tree :open)
811 "Collapse node"
812 "Expand node"))
814 (defun tree-widget-expander-p (tree)
815 "Return non-nil if the TREE tree-widget :expander has to be called.
816 That is, if TREE :args is nil."
817 (null (widget-get tree :args)))
819 (provide 'tree-widget)
821 ;; arch-tag: c3a1ada2-1663-41dc-9d16-2479ed8320e8
822 ;;; tree-widget.el ends here