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1 | \input texinfo.tex |
2 | ||
3 | @c %**start of header | |
4 | @setfilename ../info/widget | |
5 | @settitle The Emacs Widget Library | |
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6 | @syncodeindex fn cp |
7 | @syncodeindex vr cp | |
8 | @syncodeindex ky cp | |
9 | @afourpaper | |
10 | @c %**end of header | |
11 | ||
12 | @copying | |
13 | Copyright @copyright{} 2000, 2002 Free Software Foundation, Inc. | |
a159375d | 14 | |
18f952d5 | 15 | @quotation |
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16 | Permission is granted to copy, distribute and/or modify this document |
17 | under the terms of the GNU Free Documentation License, Version 1.1 or | |
18 | any later version published by the Free Software Foundation; with the | |
19 | Invariant Sections being ``The GNU Manifesto'', ``Distribution'' and | |
20 | ``GNU GENERAL PUBLIC LICENSE'', with the Front-Cover texts being ``A GNU | |
21 | Manual'', and with the Back-Cover Texts as in (a) below. A copy of the | |
22 | license is included in the section entitled ``GNU Free Documentation | |
23 | License'' in the Emacs manual. | |
24 | ||
25 | This document is part of a collection distributed under the GNU Free | |
26 | Documentation License. If you want to distribute this document | |
27 | separately from the collection, you can do so by adding a copy of the | |
28 | license to the document, as described in section 6 of the license. | |
29 | ||
30 | (a) The FSF's Back-Cover Text is: ``You have freedom to copy and modify | |
31 | this GNU Manual, like GNU software. Copies published by the Free | |
32 | Software Foundation raise funds for GNU development.'' | |
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33 | @end quotation |
34 | @end copying | |
6f7f063d | 35 | |
4c2ca4f3 | 36 | @dircategory Emacs |
6bf7aab6 | 37 | @direntry |
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38 | * Widget: (widget). The "widget" package used by the Emacs Customization |
39 | facility. | |
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40 | @end direntry |
41 | ||
42 | @node Top, Introduction, (dir), (dir) | |
43 | @comment node-name, next, previous, up | |
44 | @top The Emacs Widget Library | |
45 | ||
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46 | @menu |
47 | * Introduction:: | |
48 | * User Interface:: | |
49 | * Programming Example:: | |
50 | * Setting Up the Buffer:: | |
51 | * Basic Types:: | |
52 | * Sexp Types:: | |
53 | * Widget Properties:: | |
54 | * Defining New Widgets:: | |
55 | * Widget Browser:: | |
56 | * Widget Minor Mode:: | |
57 | * Utilities:: | |
58 | * Widget Wishlist:: | |
6f7f063d | 59 | * Index:: |
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60 | @end menu |
61 | ||
62 | @node Introduction, User Interface, Top, Top | |
63 | @comment node-name, next, previous, up | |
64 | @section Introduction | |
65 | ||
ce8abc78 RS |
66 | Most graphical user interface toolkits provide a number of standard |
67 | user interface controls (sometimes known as `widgets' or `gadgets'). | |
68 | Emacs doesn't really support anything like this, except for an | |
69 | incredibly powerful text ``widget.'' On the other hand, Emacs does | |
70 | provide the necessary primitives to implement many other widgets | |
71 | within a text buffer. The @code{widget} package simplifies this task. | |
6bf7aab6 | 72 | |
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73 | @cindex basic widgets |
74 | @cindex widgets, basic types | |
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75 | The basic widgets are: |
76 | ||
77 | @table @code | |
78 | @item link | |
79 | Areas of text with an associated action. Intended for hypertext links | |
80 | embedded in text. | |
81 | @item push-button | |
82 | Like link, but intended for stand-alone buttons. | |
83 | @item editable-field | |
84 | An editable text field. It can be either variable or fixed length. | |
85 | @item menu-choice | |
86 | Allows the user to choose one of multiple options from a menu, each | |
87 | option is itself a widget. Only the selected option will be visible in | |
88 | the buffer. | |
89 | @item radio-button-choice | |
90 | Allows the user to choose one of multiple options by activating radio | |
91 | buttons. The options are implemented as widgets. All options will be | |
92 | visible in the buffer. | |
93 | @item item | |
94 | A simple constant widget intended to be used in the @code{menu-choice} and | |
95 | @code{radio-button-choice} widgets. | |
96 | @item choice-item | |
6f7f063d | 97 | A button item only intended for use in choices. When invoked, the user |
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98 | will be asked to select another option from the choice widget. |
99 | @item toggle | |
100 | A simple @samp{on}/@samp{off} switch. | |
101 | @item checkbox | |
102 | A checkbox (@samp{[ ]}/@samp{[X]}). | |
103 | @item editable-list | |
104 | Create an editable list. The user can insert or delete items in the | |
105 | list. Each list item is itself a widget. | |
106 | @end table | |
107 | ||
6f7f063d | 108 | Now, of what possible use can support for widgets be in a text editor? |
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109 | I'm glad you asked. The answer is that widgets are useful for |
110 | implementing forms. A @dfn{form} in Emacs is a buffer where the user is | |
111 | supposed to fill out a number of fields, each of which has a specific | |
112 | meaning. The user is not supposed to change or delete any of the text | |
113 | between the fields. Examples of forms in Emacs are the @file{forms} | |
114 | package (of course), the customize buffers, the mail and news compose | |
115 | modes, and the @sc{html} form support in the @file{w3} browser. | |
116 | ||
6f7f063d | 117 | @cindex widget library, why use it |
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118 | The advantages for a programmer of using the @code{widget} package to |
119 | implement forms are: | |
120 | ||
121 | @enumerate | |
122 | @item | |
6f7f063d | 123 | More complex fields than just editable text are supported. |
6bf7aab6 | 124 | @item |
6f7f063d | 125 | You can give the users immediate feedback if they enter invalid data in a |
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126 | text field, and sometimes prevent entering invalid data. |
127 | @item | |
6f7f063d | 128 | You can have fixed sized fields, thus allowing multiple fields to be |
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129 | lined up in columns. |
130 | @item | |
131 | It is simple to query or set the value of a field. | |
132 | @item | |
6f7f063d | 133 | Editing happens in the buffer, not in the mini-buffer. |
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134 | @item |
135 | Packages using the library get a uniform look, making them easier for | |
136 | the user to learn. | |
137 | @item | |
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138 | As support for embedded graphics improve, the widget library will be |
139 | extended to use the GUI features. This means that your code using the | |
140 | widget library will also use the new graphic features automatically. | |
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141 | @end enumerate |
142 | ||
143 | In order to minimize the code that is loaded by users who does not | |
144 | create any widgets, the code has been split in two files: | |
145 | ||
6f7f063d | 146 | @cindex widget library, files |
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147 | @table @file |
148 | @item widget.el | |
149 | This will declare the user variables, define the function | |
75ba82a9 | 150 | @code{define-widget}, and autoload the function @code{widget-create}. |
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151 | @item wid-edit.el |
152 | Everything else is here, there is no reason to load it explicitly, as | |
153 | it will be autoloaded when needed. | |
154 | @end table | |
155 | ||
156 | @node User Interface, Programming Example, Introduction, Top | |
157 | @comment node-name, next, previous, up | |
158 | @section User Interface | |
159 | ||
160 | A form consist of read only text for documentation and some fields, | |
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161 | where each field contains two parts, a tag and a value. The tags are |
162 | used to identify the fields, so the documentation can refer to the | |
163 | @samp{foo field}, meaning the field tagged with @samp{Foo}. Here is an | |
164 | example form: | |
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165 | |
166 | @example | |
167 | Here is some documentation. | |
168 | ||
169 | Name: @i{My Name} @strong{Choose}: This option | |
170 | Address: @i{Some Place | |
171 | In some City | |
172 | Some country.} | |
173 | ||
174 | See also @b{_other work_} for more information. | |
175 | ||
176 | Numbers: count to three below | |
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177 | @b{[INS]} @b{[DEL]} @i{One} |
178 | @b{[INS]} @b{[DEL]} @i{Eh, two?} | |
179 | @b{[INS]} @b{[DEL]} @i{Five!} | |
180 | @b{[INS]} | |
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181 | |
182 | Select multiple: | |
183 | ||
184 | @b{[X]} This | |
185 | @b{[ ]} That | |
186 | @b{[X]} Thus | |
187 | ||
188 | Select one: | |
189 | ||
190 | @b{(*)} One | |
191 | @b{( )} Another One. | |
192 | @b{( )} A Final One. | |
193 | ||
194 | @b{[Apply Form]} @b{[Reset Form]} | |
195 | @end example | |
196 | ||
197 | The top level widgets in is example are tagged @samp{Name}, | |
198 | @samp{Choose}, @samp{Address}, @samp{_other work_}, @samp{Numbers}, | |
199 | @samp{Select multiple}, @samp{Select one}, @samp{[Apply Form]}, and | |
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200 | @samp{[Reset Form]}. There are basically two things the user can do |
201 | within a form, namely editing the editable text fields and activating | |
202 | the buttons. | |
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203 | |
204 | @subsection Editable Text Fields | |
205 | ||
206 | In the example, the value for the @samp{Name} is most likely displayed | |
207 | in an editable text field, and so are values for each of the members of | |
208 | the @samp{Numbers} list. All the normal Emacs editing operations are | |
209 | available for editing these fields. The only restriction is that each | |
210 | change you make must be contained within a single editable text field. | |
211 | For example, capitalizing all text from the middle of one field to the | |
212 | middle of another field is prohibited. | |
213 | ||
214 | Editing text fields are created by the @code{editable-field} widget. | |
215 | ||
216 | The editing text fields are highlighted with the | |
217 | @code{widget-field-face} face, making them easy to find. | |
218 | ||
219 | @deffn Face widget-field-face | |
220 | Face used for other editing fields. | |
221 | @end deffn | |
222 | ||
223 | @subsection Buttons | |
224 | ||
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225 | @cindex widget buttons |
226 | @cindex button widgets | |
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227 | Some portions of the buffer have an associated @dfn{action}, which can |
228 | be @dfn{invoked} by a standard key or mouse command. These portions | |
229 | are called @dfn{buttons}. The default commands for activating a button | |
230 | are: | |
231 | ||
232 | @table @kbd | |
233 | @item @key{RET} | |
234 | @deffn Command widget-button-press @var{pos} &optional @var{event} | |
235 | Invoke the button at @var{pos}, defaulting to point. | |
236 | If point is not located on a button, invoke the binding in | |
237 | @code{widget-global-map} (by default the global map). | |
238 | @end deffn | |
239 | ||
ce8abc78 RS |
240 | @kindex Mouse-2 @r{(on button widgets}) |
241 | @item Mouse-2 | |
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242 | @deffn Command widget-button-click @var{event} |
243 | Invoke the button at the location of the mouse pointer. If the mouse | |
244 | pointer is located in an editable text field, invoke the binding in | |
245 | @code{widget-global-map} (by default the global map). | |
246 | @end deffn | |
247 | @end table | |
248 | ||
249 | There are several different kind of buttons, all of which are present in | |
250 | the example: | |
251 | ||
252 | @table @emph | |
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253 | @cindex option field tag |
254 | @item The Option Field Tags | |
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255 | When you invoke one of these buttons, you will be asked to choose |
256 | between a number of different options. This is how you edit an option | |
257 | field. Option fields are created by the @code{menu-choice} widget. In | |
258 | the example, @samp{@b{Choose}} is an option field tag. | |
976e00f1 | 259 | @item The @samp{@b{[INS]}} and @samp{@b{[DEL]}} buttons |
6f7f063d | 260 | Activating these will insert or delete elements from an editable list. |
6bf7aab6 | 261 | The list is created by the @code{editable-list} widget. |
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262 | @cindex embedded buttons |
263 | @item Embedded Buttons | |
6bf7aab6 | 264 | The @samp{@b{_other work_}} is an example of an embedded |
6f7f063d | 265 | button. Embedded buttons are not associated with a fields, but can serve |
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266 | any purpose, such as implementing hypertext references. They are |
267 | usually created by the @code{link} widget. | |
6f7f063d | 268 | @item The @samp{@b{[ ]}} and @samp{@b{[X]}} buttons |
6bf7aab6 | 269 | Activating one of these will convert it to the other. This is useful |
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270 | for implementing multiple-choice fields. You can create it with the |
271 | @code{checkbox} widget. | |
272 | @item The @samp{@b{( )}} and @samp{@b{(*)}} buttons | |
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273 | Only one radio button in a @code{radio-button-choice} widget can be |
274 | selected at any time. When you invoke one of the unselected radio | |
275 | buttons, it will be selected and the previous selected radio button will | |
276 | become unselected. | |
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277 | @item The @samp{@b{[Apply Form]}} @samp{@b{[Reset Form]}} buttons |
278 | These are explicit buttons made with the @code{push-button} widget. The | |
279 | main difference from the @code{link} widget is that the buttons will be | |
6bf7aab6 | 280 | displayed as GUI buttons when possible. |
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281 | @end table |
282 | ||
283 | To make them easier to locate, buttons are emphasized in the buffer. | |
284 | ||
285 | @deffn Face widget-button-face | |
286 | Face used for buttons. | |
287 | @end deffn | |
288 | ||
289 | @defopt widget-mouse-face | |
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290 | Face used for highlighting a button when the mouse pointer moves across |
291 | it. | |
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292 | @end defopt |
293 | ||
294 | @subsection Navigation | |
295 | ||
296 | You can use all the normal Emacs commands to move around in a form | |
297 | buffer, plus you will have these additional commands: | |
298 | ||
299 | @table @kbd | |
300 | @item @key{TAB} | |
301 | @deffn Command widget-forward &optional count | |
302 | Move point @var{count} buttons or editing fields forward. | |
303 | @end deffn | |
304 | @item @key{M-TAB} | |
305 | @deffn Command widget-backward &optional count | |
306 | Move point @var{count} buttons or editing fields backward. | |
307 | @end deffn | |
308 | @end table | |
309 | ||
310 | @node Programming Example, Setting Up the Buffer, User Interface, Top | |
311 | @comment node-name, next, previous, up | |
312 | @section Programming Example | |
313 | ||
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314 | @cindex widgets, programming example |
315 | @cindex example of using widgets | |
6bf7aab6 DL |
316 | Here is the code to implement the user interface example (@pxref{User |
317 | Interface}). | |
318 | ||
319 | @lisp | |
320 | (require 'widget) | |
321 | ||
322 | (eval-when-compile | |
323 | (require 'wid-edit)) | |
324 | ||
325 | (defvar widget-example-repeat) | |
326 | ||
327 | (defun widget-example () | |
328 | "Create the widgets from the Widget manual." | |
329 | (interactive) | |
330 | (switch-to-buffer "*Widget Example*") | |
331 | (kill-all-local-variables) | |
332 | (make-local-variable 'widget-example-repeat) | |
333 | (let ((inhibit-read-only t)) | |
334 | (erase-buffer)) | |
335 | (widget-insert "Here is some documentation.\n\nName: ") | |
336 | (widget-create 'editable-field | |
337 | :size 13 | |
338 | "My Name") | |
339 | (widget-create 'menu-choice | |
340 | :tag "Choose" | |
341 | :value "This" | |
342 | :help-echo "Choose me, please!" | |
343 | :notify (lambda (widget &rest ignore) | |
344 | (message "%s is a good choice!" | |
345 | (widget-value widget))) | |
346 | '(item :tag "This option" :value "This") | |
347 | '(choice-item "That option") | |
348 | '(editable-field :menu-tag "No option" "Thus option")) | |
349 | (widget-insert "Address: ") | |
350 | (widget-create 'editable-field | |
351 | "Some Place\nIn some City\nSome country.") | |
352 | (widget-insert "\nSee also ") | |
353 | (widget-create 'link | |
354 | :notify (lambda (&rest ignore) | |
355 | (widget-value-set widget-example-repeat | |
356 | '("En" "To" "Tre")) | |
357 | (widget-setup)) | |
358 | "other work") | |
ec45fa10 EZ |
359 | (widget-insert |
360 | " for more information.\n\nNumbers: count to three below\n") | |
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361 | (setq widget-example-repeat |
362 | (widget-create 'editable-list | |
363 | :entry-format "%i %d %v" | |
364 | :notify (lambda (widget &rest ignore) | |
365 | (let ((old (widget-get widget | |
366 | ':example-length)) | |
367 | (new (length (widget-value widget)))) | |
368 | (unless (eq old new) | |
369 | (widget-put widget ':example-length new) | |
370 | (message "You can count to %d." new)))) | |
371 | :value '("One" "Eh, two?" "Five!") | |
372 | '(editable-field :value "three"))) | |
373 | (widget-insert "\n\nSelect multiple:\n\n") | |
374 | (widget-create 'checkbox t) | |
375 | (widget-insert " This\n") | |
376 | (widget-create 'checkbox nil) | |
377 | (widget-insert " That\n") | |
378 | (widget-create 'checkbox | |
379 | :notify (lambda (&rest ignore) (message "Tickle")) | |
380 | t) | |
381 | (widget-insert " Thus\n\nSelect one:\n\n") | |
382 | (widget-create 'radio-button-choice | |
383 | :value "One" | |
384 | :notify (lambda (widget &rest ignore) | |
385 | (message "You selected %s" | |
386 | (widget-value widget))) | |
387 | '(item "One") '(item "Another One.") '(item "A Final One.")) | |
388 | (widget-insert "\n") | |
389 | (widget-create 'push-button | |
390 | :notify (lambda (&rest ignore) | |
391 | (if (= (length (widget-value widget-example-repeat)) | |
392 | 3) | |
393 | (message "Congratulation!") | |
394 | (error "Three was the count!"))) | |
395 | "Apply Form") | |
396 | (widget-insert " ") | |
397 | (widget-create 'push-button | |
398 | :notify (lambda (&rest ignore) | |
399 | (widget-example)) | |
400 | "Reset Form") | |
401 | (widget-insert "\n") | |
402 | (use-local-map widget-keymap) | |
403 | (widget-setup)) | |
404 | @end lisp | |
405 | ||
406 | @node Setting Up the Buffer, Basic Types, Programming Example, Top | |
407 | @comment node-name, next, previous, up | |
408 | @section Setting Up the Buffer | |
409 | ||
410 | Widgets are created with @code{widget-create}, which returns a | |
411 | @dfn{widget} object. This object can be queried and manipulated by | |
412 | other widget functions, until it is deleted with @code{widget-delete}. | |
413 | After the widgets have been created, @code{widget-setup} must be called | |
414 | to enable them. | |
415 | ||
416 | @defun widget-create type [ keyword argument ]@dots{} | |
417 | Create and return a widget of type @var{type}. | |
418 | The syntax for the @var{type} argument is described in @ref{Basic Types}. | |
419 | ||
420 | The keyword arguments can be used to overwrite the keyword arguments | |
421 | that are part of @var{type}. | |
422 | @end defun | |
423 | ||
424 | @defun widget-delete widget | |
425 | Delete @var{widget} and remove it from the buffer. | |
426 | @end defun | |
427 | ||
428 | @defun widget-setup | |
6f7f063d | 429 | Set up a buffer to support widgets. |
6bf7aab6 DL |
430 | |
431 | This should be called after creating all the widgets and before allowing | |
432 | the user to edit them. | |
433 | @refill | |
434 | @end defun | |
435 | ||
436 | If you want to insert text outside the widgets in the form, the | |
437 | recommended way to do that is with @code{widget-insert}. | |
438 | ||
439 | @defun widget-insert | |
440 | Insert the arguments, either strings or characters, at point. | |
6f7f063d | 441 | The inserted text will be read-only. |
6bf7aab6 DL |
442 | @end defun |
443 | ||
444 | There is a standard widget keymap which you might find useful. | |
445 | ||
6f7f063d EZ |
446 | @findex widget-button-press |
447 | @findex widget-button-click | |
6bf7aab6 DL |
448 | @defvr Const widget-keymap |
449 | A keymap with the global keymap as its parent.@* | |
450 | @key{TAB} and @kbd{C-@key{TAB}} are bound to @code{widget-forward} and | |
ce8abc78 | 451 | @code{widget-backward}, respectively. @key{RET} and @kbd{Mouse-2} |
6bf7aab6 | 452 | are bound to @code{widget-button-press} and |
6f7f063d | 453 | @code{widget-button-click}.@refill |
6bf7aab6 DL |
454 | @end defvr |
455 | ||
456 | @defvar widget-global-map | |
457 | Keymap used by @code{widget-button-press} and @code{widget-button-click} | |
458 | when not on a button. By default this is @code{global-map}. | |
459 | @end defvar | |
460 | ||
461 | @node Basic Types, Sexp Types, Setting Up the Buffer, Top | |
462 | @comment node-name, next, previous, up | |
463 | @section Basic Types | |
464 | ||
465 | The syntax of a type specification is given below: | |
466 | ||
467 | @example | |
468 | NAME ::= (NAME [KEYWORD ARGUMENT]... ARGS) | |
469 | | NAME | |
470 | @end example | |
471 | ||
472 | Where, @var{name} is a widget name, @var{keyword} is the name of a | |
473 | property, @var{argument} is the value of the property, and @var{args} | |
474 | are interpreted in a widget specific way. | |
475 | ||
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476 | @cindex keyword arguments |
477 | The following keyword arguments that apply to all widgets: | |
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478 | |
479 | @table @code | |
6f7f063d | 480 | @vindex value@r{ keyword} |
6bf7aab6 DL |
481 | @item :value |
482 | The initial value for widgets of this type. | |
483 | ||
6f7f063d | 484 | @vindex format@r{ keyword} |
6bf7aab6 DL |
485 | @item :format |
486 | This string will be inserted in the buffer when you create a widget. | |
487 | The following @samp{%} escapes are available: | |
488 | ||
489 | @table @samp | |
490 | @item %[ | |
491 | @itemx %] | |
492 | The text inside will be marked as a button. | |
493 | ||
494 | By default, the text will be shown in @code{widget-button-face}, and | |
495 | surrounded by brackets. | |
496 | ||
497 | @defopt widget-button-prefix | |
498 | String to prefix buttons. | |
499 | @end defopt | |
500 | ||
501 | @defopt widget-button-suffix | |
502 | String to suffix buttons. | |
503 | @end defopt | |
504 | ||
505 | @item %@{ | |
506 | @itemx %@} | |
507 | The text inside will be displayed with the face specified by | |
508 | @code{:sample-face}. | |
509 | ||
510 | @item %v | |
54438eb5 | 511 | This will be replaced with the buffer representation of the widget's |
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512 | value. What this is depends on the widget type. |
513 | ||
514 | @item %d | |
515 | Insert the string specified by @code{:doc} here. | |
516 | ||
517 | @item %h | |
518 | Like @samp{%d}, with the following modifications: If the documentation | |
519 | string is more than one line, it will add a button which will toggle | |
520 | between showing only the first line, and showing the full text. | |
521 | Furthermore, if there is no @code{:doc} property in the widget, it will | |
522 | instead examine the @code{:documentation-property} property. If it is a | |
523 | lambda expression, it will be called with the widget's value as an | |
524 | argument, and the result will be used as the documentation text. | |
525 | ||
526 | @item %t | |
527 | Insert the string specified by @code{:tag} here, or the @code{princ} | |
528 | representation of the value if there is no tag. | |
529 | ||
530 | @item %% | |
531 | Insert a literal @samp{%}. | |
532 | @end table | |
533 | ||
6f7f063d | 534 | @vindex button-face@r{ keyword} |
6bf7aab6 DL |
535 | @item :button-face |
536 | Face used to highlight text inside %[ %] in the format. | |
537 | ||
6f7f063d EZ |
538 | @vindex button-prefix@r{ keyword} |
539 | @vindex button-suffix@r{ keyword} | |
6bf7aab6 DL |
540 | @item :button-prefix |
541 | @itemx :button-suffix | |
6bf7aab6 DL |
542 | Text around %[ %] in the format. |
543 | ||
544 | These can be | |
545 | @table @emph | |
546 | @item nil | |
547 | No text is inserted. | |
548 | ||
549 | @item a string | |
550 | The string is inserted literally. | |
551 | ||
552 | @item a symbol | |
553 | The value of the symbol is expanded according to this table. | |
554 | @end table | |
555 | ||
6f7f063d | 556 | @vindex doc@r{ keyword} |
6bf7aab6 DL |
557 | @item :doc |
558 | The string inserted by the @samp{%d} escape in the format | |
559 | string. | |
560 | ||
6f7f063d | 561 | @vindex tag@r{ keyword} |
6bf7aab6 DL |
562 | @item :tag |
563 | The string inserted by the @samp{%t} escape in the format | |
564 | string. | |
565 | ||
6f7f063d | 566 | @vindex tag-glyph@r{ keyword} |
6bf7aab6 | 567 | @item :tag-glyph |
6f7f063d | 568 | Name of image to use instead of the string specified by @code{:tag} on |
6bf7aab6 DL |
569 | Emacsen that supports it. |
570 | ||
6f7f063d | 571 | @vindex help-echo@r{ keyword} |
6bf7aab6 | 572 | @item :help-echo |
a159375d DL |
573 | Specifies how to display a message whenever you move to the widget with |
574 | either @code{widget-forward} or @code{widget-backward} or move the mouse | |
56600dfa | 575 | over it (using the standard @code{help-echo} mechanism). The argument |
a159375d DL |
576 | is either a string to display or a function of one argument, the widget, |
577 | which should return a string to display. | |
6bf7aab6 | 578 | |
6f7f063d | 579 | @vindex indent@r{ keyword} |
6bf7aab6 DL |
580 | @item :indent |
581 | An integer indicating the absolute number of spaces to indent children | |
582 | of this widget. | |
583 | ||
6f7f063d | 584 | @vindex offset@r{ keyword} |
6bf7aab6 DL |
585 | @item :offset |
586 | An integer indicating how many extra spaces to add to the widget's | |
587 | grandchildren compared to this widget. | |
588 | ||
6f7f063d | 589 | @vindex extra-offset@r{ keyword} |
6bf7aab6 DL |
590 | @item :extra-offset |
591 | An integer indicating how many extra spaces to add to the widget's | |
592 | children compared to this widget. | |
593 | ||
6f7f063d | 594 | @vindex notify@r{ keyword} |
6bf7aab6 DL |
595 | @item :notify |
596 | A function called each time the widget or a nested widget is changed. | |
597 | The function is called with two or three arguments. The first argument | |
598 | is the widget itself, the second argument is the widget that was | |
599 | changed, and the third argument is the event leading to the change, if | |
600 | any. | |
601 | ||
6f7f063d | 602 | @vindex menu-tag@r{ keyword} |
6bf7aab6 DL |
603 | @item :menu-tag |
604 | Tag used in the menu when the widget is used as an option in a | |
605 | @code{menu-choice} widget. | |
606 | ||
6f7f063d | 607 | @vindex menu-tag-get@r{ keyword} |
6bf7aab6 DL |
608 | @item :menu-tag-get |
609 | Function used for finding the tag when the widget is used as an option | |
610 | in a @code{menu-choice} widget. By default, the tag used will be either the | |
611 | @code{:menu-tag} or @code{:tag} property if present, or the @code{princ} | |
612 | representation of the @code{:value} property if not. | |
613 | ||
6f7f063d | 614 | @vindex match@r{ keyword} |
6bf7aab6 DL |
615 | @item :match |
616 | Should be a function called with two arguments, the widget and a value, | |
617 | and returning non-nil if the widget can represent the specified value. | |
618 | ||
6f7f063d | 619 | @vindex validate@r{ keyword} |
6bf7aab6 | 620 | @item :validate |
6f7f063d EZ |
621 | A function which takes a widget as an argument, and returns @code{nil} |
622 | if the widget's current value is valid for the widget. Otherwise it | |
623 | should return the widget containing the invalid data, and set that | |
624 | widget's @code{:error} property to a string explaining the error. | |
6bf7aab6 DL |
625 | |
626 | The following predefined function can be used: | |
627 | ||
628 | @defun widget-children-validate widget | |
629 | All the @code{:children} of @var{widget} must be valid. | |
630 | @end defun | |
631 | ||
6f7f063d | 632 | @vindex tab-order@r{ keyword} |
6bf7aab6 DL |
633 | @item :tab-order |
634 | Specify the order in which widgets are traversed with | |
635 | @code{widget-forward} or @code{widget-backward}. This is only partially | |
636 | implemented. | |
637 | ||
638 | @enumerate a | |
639 | @item | |
640 | Widgets with tabbing order @code{-1} are ignored. | |
641 | ||
642 | @item | |
643 | (Unimplemented) When on a widget with tabbing order @var{n}, go to the | |
644 | next widget in the buffer with tabbing order @var{n+1} or @code{nil}, | |
645 | whichever comes first. | |
646 | ||
647 | @item | |
648 | When on a widget with no tabbing order specified, go to the next widget | |
649 | in the buffer with a positive tabbing order, or @code{nil} | |
650 | @end enumerate | |
651 | ||
6f7f063d | 652 | @vindex parent@r{ keyword} |
6bf7aab6 | 653 | @item :parent |
a159375d | 654 | The parent of a nested widget (e.g.@: a @code{menu-choice} item or an |
6bf7aab6 DL |
655 | element of a @code{editable-list} widget). |
656 | ||
6f7f063d | 657 | @vindex sibling-args@r{ keyword} |
6bf7aab6 DL |
658 | @item :sibling-args |
659 | This keyword is only used for members of a @code{radio-button-choice} or | |
660 | @code{checklist}. The value should be a list of extra keyword | |
661 | arguments, which will be used when creating the @code{radio-button} or | |
662 | @code{checkbox} associated with this item. | |
663 | ||
664 | @end table | |
665 | ||
666 | @deffn {User Option} widget-glyph-directory | |
667 | Directory where glyphs are found. | |
668 | Widget will look here for a file with the same name as specified for the | |
6f7f063d | 669 | image, with either a @file{.xpm} (if supported) or @file{.xbm} extension. |
6bf7aab6 DL |
670 | @end deffn |
671 | ||
672 | @deffn{User Option} widget-glyph-enable | |
673 | If non-nil, allow glyphs to appear on displays where they are supported. | |
674 | @end deffn | |
675 | ||
676 | ||
677 | @menu | |
678 | * link:: | |
679 | * url-link:: | |
680 | * info-link:: | |
681 | * push-button:: | |
682 | * editable-field:: | |
683 | * text:: | |
684 | * menu-choice:: | |
685 | * radio-button-choice:: | |
686 | * item:: | |
687 | * choice-item:: | |
688 | * toggle:: | |
689 | * checkbox:: | |
690 | * checklist:: | |
691 | * editable-list:: | |
692 | * group:: | |
693 | @end menu | |
694 | ||
695 | @node link, url-link, Basic Types, Basic Types | |
696 | @comment node-name, next, previous, up | |
697 | @subsection The @code{link} Widget | |
6f7f063d | 698 | @findex link@r{ widget} |
6bf7aab6 DL |
699 | |
700 | Syntax: | |
701 | ||
702 | @example | |
703 | TYPE ::= (link [KEYWORD ARGUMENT]... [ VALUE ]) | |
704 | @end example | |
705 | ||
706 | The @var{value}, if present, is used to initialize the @code{:value} | |
707 | property. The value should be a string, which will be inserted in the | |
708 | buffer. | |
709 | ||
710 | By default the link will be shown in brackets. | |
711 | ||
712 | @defopt widget-link-prefix | |
713 | String to prefix links. | |
714 | @end defopt | |
715 | ||
716 | @defopt widget-link-suffix | |
717 | String to suffix links. | |
718 | @end defopt | |
719 | ||
720 | @node url-link, info-link, link, Basic Types | |
721 | @comment node-name, next, previous, up | |
722 | @subsection The @code{url-link} Widget | |
6f7f063d | 723 | @findex url-link@r{ widget} |
6bf7aab6 DL |
724 | |
725 | Syntax: | |
726 | ||
727 | @example | |
728 | TYPE ::= (url-link [KEYWORD ARGUMENT]... URL) | |
729 | @end example | |
730 | ||
6f7f063d | 731 | @findex browse-url-browser-function@r{, and @code{url-link} widget} |
6bf7aab6 DL |
732 | When this link is invoked, the @sc{www} browser specified by |
733 | @code{browse-url-browser-function} will be called with @var{url}. | |
734 | ||
735 | @node info-link, push-button, url-link, Basic Types | |
736 | @comment node-name, next, previous, up | |
737 | @subsection The @code{info-link} Widget | |
6f7f063d | 738 | @findex info-link@r{ widget} |
6bf7aab6 DL |
739 | |
740 | Syntax: | |
741 | ||
742 | @example | |
743 | TYPE ::= (info-link [KEYWORD ARGUMENT]... ADDRESS) | |
744 | @end example | |
745 | ||
6f7f063d | 746 | When this link is invoked, the built-in Info reader is started on |
6bf7aab6 DL |
747 | @var{address}. |
748 | ||
749 | @node push-button, editable-field, info-link, Basic Types | |
750 | @comment node-name, next, previous, up | |
751 | @subsection The @code{push-button} Widget | |
6f7f063d | 752 | @findex push-button@r{ widget} |
6bf7aab6 DL |
753 | |
754 | Syntax: | |
755 | ||
756 | @example | |
757 | TYPE ::= (push-button [KEYWORD ARGUMENT]... [ VALUE ]) | |
758 | @end example | |
759 | ||
760 | The @var{value}, if present, is used to initialize the @code{:value} | |
6f7f063d | 761 | property. The value should be a string, which will be inserted in the |
6bf7aab6 DL |
762 | buffer. |
763 | ||
764 | By default the tag will be shown in brackets. | |
765 | ||
766 | @defopt widget-push-button-prefix | |
767 | String to prefix push buttons. | |
768 | @end defopt | |
769 | ||
770 | @defopt widget-push-button-suffix | |
771 | String to suffix push buttons. | |
772 | @end defopt | |
773 | ||
774 | @node editable-field, text, push-button, Basic Types | |
775 | @comment node-name, next, previous, up | |
776 | @subsection The @code{editable-field} Widget | |
6f7f063d | 777 | @findex editable-field@r{ widget} |
6bf7aab6 DL |
778 | |
779 | Syntax: | |
780 | ||
781 | @example | |
782 | TYPE ::= (editable-field [KEYWORD ARGUMENT]... [ VALUE ]) | |
783 | @end example | |
784 | ||
785 | The @var{value}, if present, is used to initialize the @code{:value} | |
786 | property. The value should be a string, which will be inserted in | |
787 | field. This widget will match all string values. | |
788 | ||
6f7f063d | 789 | The following extra properties are recognized: |
6bf7aab6 DL |
790 | |
791 | @table @code | |
6f7f063d | 792 | @vindex size@r{ keyword} |
6bf7aab6 DL |
793 | @item :size |
794 | The width of the editable field.@* | |
795 | By default the field will reach to the end of the line. | |
796 | ||
6f7f063d | 797 | @vindex value-face@r{ keyword} |
6bf7aab6 DL |
798 | @item :value-face |
799 | Face used for highlighting the editable field. Default is | |
6f7f063d | 800 | @code{widget-field-face}, see @ref{User Interface}. |
6bf7aab6 | 801 | |
6f7f063d | 802 | @vindex secret@r{ keyword} |
6bf7aab6 | 803 | @item :secret |
a159375d | 804 | Character used to display the value. You can set this to e.g.@: @code{?*} |
6bf7aab6 | 805 | if the field contains a password or other secret information. By |
6f7f063d | 806 | default, this is nil, and the value is not secret. |
6bf7aab6 | 807 | |
6f7f063d | 808 | @vindex valid-regexp@r{ keyword} |
6bf7aab6 DL |
809 | @item :valid-regexp |
810 | By default the @code{:validate} function will match the content of the | |
811 | field with the value of this attribute. The default value is @code{""} | |
812 | which matches everything. | |
813 | ||
6f7f063d EZ |
814 | @vindex keymap@r{ keyword} |
815 | @vindex widget-field-keymap | |
6bf7aab6 DL |
816 | @item :keymap |
817 | Keymap used in the editable field. The default value is | |
818 | @code{widget-field-keymap}, which allows you to use all the normal | |
6f7f063d EZ |
819 | editing commands, even if the buffer's major mode suppresses some of |
820 | them. Pressing @key{RET} invokes the function specified by | |
821 | @code{:action}. | |
6bf7aab6 DL |
822 | @end table |
823 | ||
824 | @node text, menu-choice, editable-field, Basic Types | |
825 | @comment node-name, next, previous, up | |
826 | @subsection The @code{text} Widget | |
6f7f063d | 827 | @findex text@r{ widget} |
6bf7aab6 | 828 | |
6f7f063d | 829 | @vindex widget-text-keymap |
6bf7aab6 DL |
830 | This is just like @code{editable-field}, but intended for multiline text |
831 | fields. The default @code{:keymap} is @code{widget-text-keymap}, which | |
6f7f063d | 832 | does not rebind the @key{RET} key. |
6bf7aab6 DL |
833 | |
834 | @node menu-choice, radio-button-choice, text, Basic Types | |
835 | @comment node-name, next, previous, up | |
836 | @subsection The @code{menu-choice} Widget | |
6f7f063d | 837 | @findex menu-choice@r{ widget} |
6bf7aab6 DL |
838 | |
839 | Syntax: | |
840 | ||
841 | @example | |
842 | TYPE ::= (menu-choice [KEYWORD ARGUMENT]... TYPE ... ) | |
843 | @end example | |
844 | ||
54438eb5 DL |
845 | The @var{type} argument represents each possible choice. The widget's |
846 | value will be that of the chosen @var{type} argument. This widget will | |
847 | match any value matching at least one of the specified @var{type} | |
848 | arguments. | |
6bf7aab6 DL |
849 | |
850 | @table @code | |
6f7f063d | 851 | @vindex void@r{ keyword} |
6bf7aab6 DL |
852 | @item :void |
853 | Widget type used as a fallback when the value does not match any of the | |
854 | specified @var{type} arguments. | |
855 | ||
6f7f063d | 856 | @vindex case-fold@r{ keyword} |
6bf7aab6 DL |
857 | @item :case-fold |
858 | Set this to nil if you don't want to ignore case when prompting for a | |
859 | choice through the minibuffer. | |
860 | ||
6f7f063d | 861 | @vindex children@r{ keyword} |
6bf7aab6 | 862 | @item :children |
6f7f063d EZ |
863 | A list whose @code{car} is the widget representing the currently chosen |
864 | type in the buffer. | |
6bf7aab6 | 865 | |
6f7f063d | 866 | @vindex choice@r{ keyword} |
6bf7aab6 | 867 | @item :choice |
6f7f063d | 868 | The current chosen type. |
6bf7aab6 | 869 | |
6f7f063d | 870 | @vindex args@r{ keyword} |
6bf7aab6 DL |
871 | @item :args |
872 | The list of types. | |
873 | @end table | |
874 | ||
875 | @node radio-button-choice, item, menu-choice, Basic Types | |
876 | @comment node-name, next, previous, up | |
877 | @subsection The @code{radio-button-choice} Widget | |
6f7f063d | 878 | @findex radio-button-choice@r{ widget} |
6bf7aab6 DL |
879 | |
880 | Syntax: | |
881 | ||
882 | @example | |
883 | TYPE ::= (radio-button-choice [KEYWORD ARGUMENT]... TYPE ... ) | |
884 | @end example | |
885 | ||
54438eb5 DL |
886 | The @var{type} argument represents each possible choice. The widget's |
887 | value will be that of the chosen @var{type} argument. This widget will | |
888 | match any value matching at least one of the specified @var{type} | |
889 | arguments. | |
6bf7aab6 DL |
890 | |
891 | The following extra properties are recognized. | |
892 | ||
893 | @table @code | |
6f7f063d | 894 | @vindex entry-format@r{ keyword} |
6bf7aab6 DL |
895 | @item :entry-format |
896 | This string will be inserted for each entry in the list. | |
897 | The following @samp{%} escapes are available: | |
898 | @table @samp | |
899 | @item %v | |
6f7f063d | 900 | Replace with the buffer representation of the @var{type} widget. |
6bf7aab6 DL |
901 | @item %b |
902 | Replace with the radio button. | |
903 | @item %% | |
904 | Insert a literal @samp{%}. | |
905 | @end table | |
906 | ||
6f7f063d EZ |
907 | @vindex button-args@r{ keyword} |
908 | @item :button-args | |
6bf7aab6 | 909 | A list of keywords to pass to the radio buttons. Useful for setting |
a159375d | 910 | e.g.@: the @samp{:help-echo} for each button. |
6bf7aab6 | 911 | |
6f7f063d | 912 | @vindex buttons@r{ keyword} |
6bf7aab6 DL |
913 | @item :buttons |
914 | The widgets representing the radio buttons. | |
915 | ||
6f7f063d | 916 | @vindex children@r{ keyword} |
6bf7aab6 DL |
917 | @item :children |
918 | The widgets representing each type. | |
919 | ||
6f7f063d | 920 | @vindex choice@r{ keyword} |
6bf7aab6 DL |
921 | @item :choice |
922 | The current chosen type | |
923 | ||
6f7f063d | 924 | @vindex args@r{ keyword} |
6bf7aab6 DL |
925 | @item :args |
926 | The list of types. | |
927 | @end table | |
928 | ||
929 | You can add extra radio button items to a @code{radio-button-choice} | |
930 | widget after it has been created with the function | |
931 | @code{widget-radio-add-item}. | |
932 | ||
933 | @defun widget-radio-add-item widget type | |
6f7f063d EZ |
934 | Add to @code{radio-button-choice} widget @var{widget} a new radio button |
935 | item of type @var{type}. | |
6bf7aab6 DL |
936 | @end defun |
937 | ||
938 | Please note that such items added after the @code{radio-button-choice} | |
939 | widget has been created will @strong{not} be properly destructed when | |
940 | you call @code{widget-delete}. | |
941 | ||
942 | @node item, choice-item, radio-button-choice, Basic Types | |
943 | @comment node-name, next, previous, up | |
944 | @subsection The @code{item} Widget | |
6f7f063d | 945 | @findex item@r{ widget} |
6bf7aab6 DL |
946 | |
947 | Syntax: | |
948 | ||
949 | @example | |
950 | ITEM ::= (item [KEYWORD ARGUMENT]... VALUE) | |
951 | @end example | |
952 | ||
953 | The @var{value}, if present, is used to initialize the @code{:value} | |
954 | property. The value should be a string, which will be inserted in the | |
955 | buffer. This widget will only match the specified value. | |
956 | ||
957 | @node choice-item, toggle, item, Basic Types | |
958 | @comment node-name, next, previous, up | |
959 | @subsection The @code{choice-item} Widget | |
6f7f063d | 960 | @findex choice-item@r{ widget} |
6bf7aab6 DL |
961 | |
962 | Syntax: | |
963 | ||
964 | @example | |
965 | ITEM ::= (choice-item [KEYWORD ARGUMENT]... VALUE) | |
966 | @end example | |
967 | ||
968 | The @var{value}, if present, is used to initialize the @code{:value} | |
969 | property. The value should be a string, which will be inserted in the | |
970 | buffer as a button. Activating the button of a @code{choice-item} is | |
971 | equivalent to activating the parent widget. This widget will only match | |
972 | the specified value. | |
973 | ||
974 | @node toggle, checkbox, choice-item, Basic Types | |
975 | @comment node-name, next, previous, up | |
976 | @subsection The @code{toggle} Widget | |
6f7f063d | 977 | @findex toggle@r{ widget} |
6bf7aab6 DL |
978 | |
979 | Syntax: | |
980 | ||
981 | @example | |
982 | TYPE ::= (toggle [KEYWORD ARGUMENT]...) | |
983 | @end example | |
984 | ||
6f7f063d EZ |
985 | The widget has two possible states, @samp{on} and @samp{off}, which |
986 | correspond to a @code{t} or @code{nil} value, respectively. | |
6bf7aab6 | 987 | |
6f7f063d | 988 | The following extra properties are recognized: |
6bf7aab6 DL |
989 | |
990 | @table @code | |
991 | @item :on | |
6f7f063d EZ |
992 | A string representing the @samp{on} state. By default the string |
993 | @samp{on}. | |
6bf7aab6 | 994 | @item :off |
6f7f063d EZ |
995 | A string representing the @samp{off} state. By default the string |
996 | @samp{off}. | |
997 | @vindex on-glyph@r{ keyword} | |
6bf7aab6 | 998 | @item :on-glyph |
6f7f063d EZ |
999 | Name of a glyph to be used instead of the @samp{:on} text string, on |
1000 | emacsen that supports this. | |
1001 | @vindex off-glyph@r{ keyword} | |
6bf7aab6 | 1002 | @item :off-glyph |
6f7f063d EZ |
1003 | Name of a glyph to be used instead of the @samp{:off} text string, on |
1004 | emacsen that supports this. | |
6bf7aab6 DL |
1005 | @end table |
1006 | ||
1007 | @node checkbox, checklist, toggle, Basic Types | |
1008 | @comment node-name, next, previous, up | |
1009 | @subsection The @code{checkbox} Widget | |
6f7f063d | 1010 | @findex checkbox@r{ widget} |
6bf7aab6 | 1011 | |
6f7f063d EZ |
1012 | This widget has two possible states, @samp{selected} and |
1013 | @samp{unselected}, which corresponds to a @code{t} or @code{nil} value. | |
6bf7aab6 DL |
1014 | |
1015 | Syntax: | |
1016 | ||
1017 | @example | |
1018 | TYPE ::= (checkbox [KEYWORD ARGUMENT]...) | |
1019 | @end example | |
1020 | ||
1021 | @node checklist, editable-list, checkbox, Basic Types | |
1022 | @comment node-name, next, previous, up | |
1023 | @subsection The @code{checklist} Widget | |
6f7f063d | 1024 | @findex checklist@r{ widget} |
6bf7aab6 DL |
1025 | |
1026 | Syntax: | |
1027 | ||
1028 | @example | |
1029 | TYPE ::= (checklist [KEYWORD ARGUMENT]... TYPE ... ) | |
1030 | @end example | |
1031 | ||
6f7f063d EZ |
1032 | The @var{type} arguments represent each checklist item. The widget's |
1033 | value will be a list containing the values of all checked @var{type} | |
54438eb5 DL |
1034 | arguments. The checklist widget will match a list whose elements all |
1035 | match at least one of the specified @var{type} arguments. | |
6bf7aab6 | 1036 | |
6f7f063d | 1037 | The following extra properties are recognized: |
6bf7aab6 DL |
1038 | |
1039 | @table @code | |
6f7f063d | 1040 | @vindex entry-format@r{ keyword} |
6bf7aab6 DL |
1041 | @item :entry-format |
1042 | This string will be inserted for each entry in the list. | |
1043 | The following @samp{%} escapes are available: | |
1044 | @table @samp | |
1045 | @item %v | |
1046 | Replaced with the buffer representation of the @var{type} widget. | |
1047 | @item %b | |
1048 | Replace with the checkbox. | |
1049 | @item %% | |
1050 | Insert a literal @samp{%}. | |
1051 | @end table | |
1052 | ||
6f7f063d | 1053 | @vindex greedy@r{ keyword} |
6bf7aab6 | 1054 | @item :greedy |
54438eb5 | 1055 | Usually a checklist will only match if the items are in the exact |
6bf7aab6 DL |
1056 | sequence given in the specification. By setting @code{:greedy} to |
1057 | non-nil, it will allow the items to come in any sequence. However, if | |
1058 | you extract the value they will be in the sequence given in the | |
a159375d | 1059 | checklist, i.e.@: the original sequence is forgotten. |
6bf7aab6 | 1060 | |
6f7f063d | 1061 | @vindex button-args@r{ keyword} |
a159375d | 1062 | @item :button-args |
6bf7aab6 | 1063 | A list of keywords to pass to the checkboxes. Useful for setting |
a159375d | 1064 | e.g.@: the @samp{:help-echo} for each checkbox. |
6bf7aab6 | 1065 | |
6f7f063d | 1066 | @vindex buttons@r{ keyword} |
6bf7aab6 DL |
1067 | @item :buttons |
1068 | The widgets representing the checkboxes. | |
1069 | ||
6f7f063d | 1070 | @vindex children@r{ keyword} |
6bf7aab6 DL |
1071 | @item :children |
1072 | The widgets representing each type. | |
1073 | ||
6f7f063d | 1074 | @vindex args@r{ keyword} |
6bf7aab6 DL |
1075 | @item :args |
1076 | The list of types. | |
1077 | @end table | |
1078 | ||
1079 | @node editable-list, group, checklist, Basic Types | |
1080 | @comment node-name, next, previous, up | |
1081 | @subsection The @code{editable-list} Widget | |
6f7f063d | 1082 | @findex editable-list@r{ widget} |
6bf7aab6 DL |
1083 | |
1084 | Syntax: | |
1085 | ||
1086 | @example | |
1087 | TYPE ::= (editable-list [KEYWORD ARGUMENT]... TYPE) | |
1088 | @end example | |
1089 | ||
1090 | The value is a list, where each member represents one widget of type | |
1091 | @var{type}. | |
1092 | ||
6f7f063d | 1093 | The following extra properties are recognized: |
6bf7aab6 DL |
1094 | |
1095 | @table @code | |
6f7f063d | 1096 | @vindex entry-format@r{ keyword} |
6bf7aab6 DL |
1097 | @item :entry-format |
1098 | This string will be inserted for each entry in the list. | |
1099 | The following @samp{%} escapes are available: | |
1100 | @table @samp | |
1101 | @item %v | |
1102 | This will be replaced with the buffer representation of the @var{type} | |
1103 | widget. | |
1104 | @item %i | |
976e00f1 | 1105 | Insert the @b{[INS]} button. |
6bf7aab6 DL |
1106 | @item %d |
1107 | Insert the @b{[DEL]} button. | |
1108 | @item %% | |
1109 | Insert a literal @samp{%}. | |
1110 | @end table | |
1111 | ||
976e00f1 DL |
1112 | @vindex insert-button-args@r{ keyword} |
1113 | @item :insert-button-args | |
6bf7aab6 DL |
1114 | A list of keyword arguments to pass to the insert buttons. |
1115 | ||
6f7f063d | 1116 | @vindex delete-button-args@r{ keyword} |
6bf7aab6 DL |
1117 | @item :delete-button-args |
1118 | A list of keyword arguments to pass to the delete buttons. | |
1119 | ||
6f7f063d | 1120 | @vindex append-button-args@r{ keyword} |
6bf7aab6 DL |
1121 | @item :append-button-args |
1122 | A list of keyword arguments to pass to the trailing insert button. | |
1123 | ||
6f7f063d | 1124 | @vindex buttons@r{ keyword} |
6bf7aab6 DL |
1125 | @item :buttons |
1126 | The widgets representing the insert and delete buttons. | |
1127 | ||
6f7f063d | 1128 | @vindex children@r{ keyword} |
6bf7aab6 DL |
1129 | @item :children |
1130 | The widgets representing the elements of the list. | |
1131 | ||
6f7f063d | 1132 | @vindex args@r{ keyword} |
6bf7aab6 | 1133 | @item :args |
6f7f063d | 1134 | List whose @code{car} is the type of the list elements. |
6bf7aab6 DL |
1135 | @end table |
1136 | ||
1137 | @node group, , editable-list, Basic Types | |
1138 | @comment node-name, next, previous, up | |
1139 | @subsection The @code{group} Widget | |
6f7f063d | 1140 | @findex group@r{ widget} |
6bf7aab6 | 1141 | |
6f7f063d | 1142 | This widget simply group other widgets together. |
6bf7aab6 DL |
1143 | |
1144 | Syntax: | |
1145 | ||
1146 | @example | |
1147 | TYPE ::= (group [KEYWORD ARGUMENT]... TYPE...) | |
1148 | @end example | |
1149 | ||
1150 | The value is a list, with one member for each @var{type}. | |
1151 | ||
1152 | @node Sexp Types, Widget Properties, Basic Types, Top | |
1153 | @comment | |
1154 | @section Sexp Types | |
6f7f063d | 1155 | @cindex sexp types |
6bf7aab6 | 1156 | |
6f7f063d EZ |
1157 | A number of widgets for editing @dfn{s-expressions} (lisp types), sexp |
1158 | for short, are also available. These basically fall in several | |
1159 | categories described in this section. | |
6bf7aab6 DL |
1160 | |
1161 | @menu | |
1162 | * constants:: | |
1163 | * generic:: | |
1164 | * atoms:: | |
1165 | * composite:: | |
1166 | @end menu | |
1167 | ||
1168 | @node constants, generic, Sexp Types, Sexp Types | |
1169 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1170 | @subsection The Constant Widgets |
1171 | @cindex constant widgets | |
6bf7aab6 DL |
1172 | |
1173 | The @code{const} widget can contain any lisp expression, but the user is | |
6f7f063d EZ |
1174 | prohibited from editing it, which is mainly useful as a component of one |
1175 | of the composite widgets. | |
6bf7aab6 | 1176 | |
6f7f063d | 1177 | The syntax for the @code{const} widget is: |
6bf7aab6 DL |
1178 | |
1179 | @example | |
1180 | TYPE ::= (const [KEYWORD ARGUMENT]... [ VALUE ]) | |
1181 | @end example | |
1182 | ||
1183 | The @var{value}, if present, is used to initialize the @code{:value} | |
1184 | property and can be any s-expression. | |
1185 | ||
1186 | @deffn Widget const | |
1187 | This will display any valid s-expression in an immutable part of the | |
1188 | buffer. | |
1189 | @end deffn | |
1190 | ||
1191 | There are two variations of the @code{const} widget, namely | |
1192 | @code{variable-item} and @code{function-item}. These should contain a | |
1193 | symbol with a variable or function binding. The major difference from | |
1194 | the @code{const} widget is that they will allow the user to see the | |
1195 | variable or function documentation for the symbol. | |
1196 | ||
1197 | @deffn Widget variable-item | |
1198 | An immutable symbol that is bound as a variable. | |
1199 | @end deffn | |
1200 | ||
1201 | @deffn Widget function-item | |
1202 | An immutable symbol that is bound as a function. | |
1203 | @end deffn | |
1204 | ||
1205 | @node generic, atoms, constants, Sexp Types | |
1206 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1207 | @subsection Generic Sexp Widget |
1208 | @cindex generic sexp widget | |
6bf7aab6 DL |
1209 | |
1210 | The @code{sexp} widget can contain any lisp expression, and allows the | |
1211 | user to edit it inline in the buffer. | |
1212 | ||
6f7f063d | 1213 | The syntax for the @code{sexp} widget is: |
6bf7aab6 DL |
1214 | |
1215 | @example | |
1216 | TYPE ::= (sexp [KEYWORD ARGUMENT]... [ VALUE ]) | |
1217 | @end example | |
1218 | ||
1219 | @deffn Widget sexp | |
1220 | This will allow you to edit any valid s-expression in an editable buffer | |
1221 | field. | |
1222 | ||
1223 | The @code{sexp} widget takes the same keyword arguments as the | |
6f7f063d | 1224 | @code{editable-field} widget. @xref{editable-field}. |
6bf7aab6 DL |
1225 | @end deffn |
1226 | ||
1227 | @node atoms, composite, generic, Sexp Types | |
1228 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1229 | @subsection Atomic Sexp Widgets |
1230 | @cindex atomic sexp widget | |
6bf7aab6 | 1231 | |
6f7f063d EZ |
1232 | The atoms are s-expressions that do not consist of other s-expressions. |
1233 | For example, a string, a file name, or a symbol are atoms, while a list | |
1234 | is a composite type. You can edit the value of an atom with the | |
1235 | following widgets. | |
6bf7aab6 | 1236 | |
6f7f063d | 1237 | The syntax for all the atoms are: |
6bf7aab6 DL |
1238 | |
1239 | @example | |
1240 | TYPE ::= (NAME [KEYWORD ARGUMENT]... [ VALUE ]) | |
1241 | @end example | |
1242 | ||
1243 | The @var{value}, if present, is used to initialize the @code{:value} | |
1244 | property and must be an expression of the same type as the widget. | |
6f7f063d | 1245 | That is, the string widget can only be initialized with a string. |
6bf7aab6 DL |
1246 | |
1247 | All the atom widgets take the same keyword arguments as the | |
6f7f063d | 1248 | @code{editable-field} widget. @xref{editable-field}. |
6bf7aab6 DL |
1249 | |
1250 | @deffn Widget string | |
1251 | Allows you to edit a string in an editable field. | |
1252 | @end deffn | |
1253 | ||
1254 | @deffn Widget regexp | |
1255 | Allows you to edit a regular expression in an editable field. | |
1256 | @end deffn | |
1257 | ||
1258 | @deffn Widget character | |
1259 | Allows you to enter a character in an editable field. | |
1260 | @end deffn | |
1261 | ||
1262 | @deffn Widget file | |
1263 | Allows you to edit a file name in an editable field. If you invoke | |
1264 | the tag button, you can edit the file name in the mini-buffer with | |
1265 | completion. | |
1266 | ||
1267 | Keywords: | |
1268 | @table @code | |
6f7f063d | 1269 | @vindex must-match@r{ keyword} |
6bf7aab6 DL |
1270 | @item :must-match |
1271 | If this is set to non-nil, only existing file names will be allowed in | |
1272 | the minibuffer. | |
1273 | @end table | |
1274 | @end deffn | |
1275 | ||
1276 | @deffn Widget directory | |
1277 | Allows you to edit a directory name in an editable field. | |
1278 | Similar to the @code{file} widget. | |
1279 | @end deffn | |
1280 | ||
1281 | @deffn Widget symbol | |
1282 | Allows you to edit a lisp symbol in an editable field. | |
1283 | @end deffn | |
1284 | ||
1285 | @deffn Widget function | |
1286 | Allows you to edit a lambda expression, or a function name with completion. | |
1287 | @end deffn | |
1288 | ||
1289 | @deffn Widget variable | |
1290 | Allows you to edit a variable name, with completion. | |
1291 | @end deffn | |
1292 | ||
1293 | @deffn Widget integer | |
1294 | Allows you to edit an integer in an editable field. | |
1295 | @end deffn | |
1296 | ||
1297 | @deffn Widget number | |
1298 | Allows you to edit a number in an editable field. | |
1299 | @end deffn | |
1300 | ||
1301 | @deffn Widget boolean | |
1302 | Allows you to edit a boolean. In lisp this means a variable which is | |
1303 | either nil meaning false, or non-nil meaning true. | |
1304 | @end deffn | |
1305 | ||
1306 | ||
1307 | @node composite, , atoms, Sexp Types | |
1308 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1309 | @subsection Composite Sexp Widgets |
1310 | @cindex composite sexp widgets | |
6bf7aab6 | 1311 | |
6f7f063d | 1312 | The syntax for the composite widget is: |
6bf7aab6 DL |
1313 | |
1314 | @example | |
1315 | TYPE ::= (NAME [KEYWORD ARGUMENT]... COMPONENT...) | |
1316 | @end example | |
1317 | ||
6f7f063d EZ |
1318 | @noindent |
1319 | where each @var{component} must be a widget type. Each component widget | |
1320 | will be displayed in the buffer, and will be editable by the user. | |
6bf7aab6 DL |
1321 | |
1322 | @deffn Widget cons | |
6f7f063d EZ |
1323 | The value of a @code{cons} widget is a cons-cell where the @code{car} is |
1324 | the value of the first component and the @code{cdr} is the value of the | |
1325 | second component. There must be exactly two components. | |
6bf7aab6 DL |
1326 | @end deffn |
1327 | ||
1328 | @deffn Widget list | |
1329 | The value of a @code{list} widget is a list containing the value of | |
1330 | each of its component. | |
1331 | @end deffn | |
1332 | ||
1333 | @deffn Widget vector | |
1334 | The value of a @code{vector} widget is a vector containing the value of | |
1335 | each of its component. | |
1336 | @end deffn | |
1337 | ||
1338 | The above suffice for specifying fixed size lists and vectors. To get | |
1339 | variable length lists and vectors, you can use a @code{choice}, | |
6f7f063d | 1340 | @code{set}, or @code{repeat} widgets together with the @code{:inline} |
6bf7aab6 DL |
1341 | keywords. If any component of a composite widget has the @code{:inline} |
1342 | keyword set, its value must be a list which will then be spliced into | |
1343 | the composite. For example, to specify a list whose first element must | |
1344 | be a file name, and whose remaining arguments should either by the | |
1345 | symbol @code{t} or two files, you can use the following widget | |
1346 | specification: | |
1347 | ||
1348 | @example | |
1349 | (list file | |
1350 | (choice (const t) | |
1351 | (list :inline t | |
1352 | :value ("foo" "bar") | |
1353 | string string))) | |
1354 | @end example | |
1355 | ||
1356 | The value of a widget of this type will either have the form | |
6f7f063d | 1357 | @code{(file t)} or @code{(file string string)}. |
6bf7aab6 DL |
1358 | |
1359 | This concept of inline is probably hard to understand. It was certainly | |
6f7f063d | 1360 | hard to implement, so instead of confusing you more by trying to explain |
54438eb5 | 1361 | it here, I'll just suggest you meditate over it for a while. |
6bf7aab6 DL |
1362 | |
1363 | @deffn Widget choice | |
54438eb5 DL |
1364 | Allows you to edit a sexp which may have one of a fixed set of types. |
1365 | It is currently implemented with the @code{choice-menu} basic widget, | |
1366 | and has a similar syntax. | |
6bf7aab6 DL |
1367 | @end deffn |
1368 | ||
1369 | @deffn Widget set | |
1370 | Allows you to specify a type which must be a list whose elements all | |
6f7f063d EZ |
1371 | belong to given set. The elements of the list are not significant. |
1372 | This is implemented on top of the @code{checklist} basic widget, and has | |
1373 | a similar syntax. | |
6bf7aab6 DL |
1374 | @end deffn |
1375 | ||
1376 | @deffn Widget repeat | |
1377 | Allows you to specify a variable length list whose members are all of | |
6f7f063d EZ |
1378 | the same type. Implemented on top of the @code{editable-list} basic |
1379 | widget, and has a similar syntax. | |
6bf7aab6 DL |
1380 | @end deffn |
1381 | ||
1382 | @node Widget Properties, Defining New Widgets, Sexp Types, Top | |
1383 | @comment node-name, next, previous, up | |
1384 | @section Properties | |
6f7f063d EZ |
1385 | @cindex properties of widgets |
1386 | @cindex widget properties | |
6bf7aab6 DL |
1387 | |
1388 | You can examine or set the value of a widget by using the widget object | |
1389 | that was returned by @code{widget-create}. | |
1390 | ||
1391 | @defun widget-value widget | |
1392 | Return the current value contained in @var{widget}. | |
1393 | It is an error to call this function on an uninitialized widget. | |
1394 | @end defun | |
1395 | ||
1396 | @defun widget-value-set widget value | |
1397 | Set the value contained in @var{widget} to @var{value}. | |
1398 | It is an error to call this function with an invalid @var{value}. | |
1399 | @end defun | |
1400 | ||
1401 | @strong{Important:} You @emph{must} call @code{widget-setup} after | |
1402 | modifying the value of a widget before the user is allowed to edit the | |
1403 | widget again. It is enough to call @code{widget-setup} once if you | |
1404 | modify multiple widgets. This is currently only necessary if the widget | |
1405 | contains an editing field, but may be necessary for other widgets in the | |
1406 | future. | |
1407 | ||
1408 | If your application needs to associate some information with the widget | |
1409 | objects, for example a reference to the item being edited, it can be | |
1410 | done with @code{widget-put} and @code{widget-get}. The property names | |
1411 | must begin with a @samp{:}. | |
1412 | ||
1413 | @defun widget-put widget property value | |
1414 | In @var{widget} set @var{property} to @var{value}. | |
1415 | @var{property} should be a symbol, while @var{value} can be anything. | |
1416 | @end defun | |
1417 | ||
1418 | @defun widget-get widget property | |
1419 | In @var{widget} return the value for @var{property}. | |
1420 | @var{property} should be a symbol, the value is what was last set by | |
1421 | @code{widget-put} for @var{property}. | |
1422 | @end defun | |
1423 | ||
1424 | @defun widget-member widget property | |
1425 | Non-nil if @var{widget} has a value (even nil) for property @var{property}. | |
1426 | @end defun | |
1427 | ||
1428 | Occasionally it can be useful to know which kind of widget you have, | |
a159375d | 1429 | i.e.@: the name of the widget type you gave when the widget was created. |
6bf7aab6 DL |
1430 | |
1431 | @defun widget-type widget | |
1432 | Return the name of @var{widget}, a symbol. | |
1433 | @end defun | |
1434 | ||
6f7f063d EZ |
1435 | @cindex active widget |
1436 | @cindex inactive widget | |
1437 | @cindex activate a widget | |
1438 | @cindex deactivate a widget | |
6bf7aab6 DL |
1439 | Widgets can be in two states: active, which means they are modifiable by |
1440 | the user, or inactive, which means they cannot be modified by the user. | |
1441 | You can query or set the state with the following code: | |
1442 | ||
1443 | @lisp | |
1444 | ;; Examine if @var{widget} is active or not. | |
1445 | (if (widget-apply @var{widget} :active) | |
1446 | (message "Widget is active.") | |
1447 | (message "Widget is inactive.") | |
1448 | ||
1449 | ;; Make @var{widget} inactive. | |
1450 | (widget-apply @var{widget} :deactivate) | |
1451 | ||
1452 | ;; Make @var{widget} active. | |
1453 | (widget-apply @var{widget} :activate) | |
1454 | @end lisp | |
1455 | ||
54438eb5 DL |
1456 | A widget is inactive if it, or any of its ancestors (found by |
1457 | following the @code{:parent} link), have been deactivated. To make sure | |
1458 | a widget is really active, you must therefore activate both it and | |
6bf7aab6 DL |
1459 | all its ancestors. |
1460 | ||
1461 | @lisp | |
1462 | (while widget | |
1463 | (widget-apply widget :activate) | |
1464 | (setq widget (widget-get widget :parent))) | |
1465 | @end lisp | |
1466 | ||
1467 | You can check if a widget has been made inactive by examining the value | |
54438eb5 DL |
1468 | of the @code{:inactive} keyword. If this is non-nil, the widget itself |
1469 | has been deactivated. This is different from using the @code{:active} | |
1470 | keyword, in that the latter tells you if the widget @strong{or} any of | |
1471 | its ancestors have been deactivated. Do not attempt to set the | |
6bf7aab6 | 1472 | @code{:inactive} keyword directly. Use the @code{:activate} |
54438eb5 | 1473 | @code{:deactivate} keywords instead. |
6bf7aab6 DL |
1474 | |
1475 | ||
1476 | @node Defining New Widgets, Widget Browser, Widget Properties, Top | |
1477 | @comment node-name, next, previous, up | |
1478 | @section Defining New Widgets | |
6f7f063d EZ |
1479 | @cindex new widgets |
1480 | @cindex defining new widgets | |
6bf7aab6 | 1481 | |
75ba82a9 | 1482 | You can define specialized widgets with @code{define-widget}. It allows |
6bf7aab6 | 1483 | you to create a shorthand for more complex widgets, including specifying |
54438eb5 | 1484 | component widgets and new default values for the keyword |
6bf7aab6 DL |
1485 | arguments. |
1486 | ||
75ba82a9 | 1487 | @defun define-widget name class doc &rest args |
6bf7aab6 DL |
1488 | Define a new widget type named @var{name} from @code{class}. |
1489 | ||
1490 | @var{name} and class should both be symbols, @code{class} should be one | |
1491 | of the existing widget types. | |
1492 | ||
1493 | The third argument @var{DOC} is a documentation string for the widget. | |
1494 | ||
1495 | After the new widget has been defined, the following two calls will | |
1496 | create identical widgets: | |
1497 | ||
1498 | @itemize @bullet | |
1499 | @item | |
1500 | @lisp | |
1501 | (widget-create @var{name}) | |
1502 | @end lisp | |
1503 | ||
1504 | @item | |
1505 | @lisp | |
1506 | (apply widget-create @var{class} @var{args}) | |
1507 | @end lisp | |
1508 | @end itemize | |
1509 | ||
1510 | @end defun | |
1511 | ||
75ba82a9 | 1512 | Using @code{define-widget} just stores the definition of the widget type |
54438eb5 | 1513 | in the @code{widget-type} property of @var{name}, which is what |
6bf7aab6 DL |
1514 | @code{widget-create} uses. |
1515 | ||
6f7f063d | 1516 | If you only want to specify defaults for keywords with no complex |
6bf7aab6 DL |
1517 | conversions, you can use @code{identity} as your conversion function. |
1518 | ||
1519 | The following additional keyword arguments are useful when defining new | |
1520 | widgets: | |
1521 | @table @code | |
6f7f063d | 1522 | @vindex convert-widget@r{ keyword} |
6bf7aab6 DL |
1523 | @item :convert-widget |
1524 | Function to convert a widget type before creating a widget of that | |
1525 | type. It takes a widget type as an argument, and returns the converted | |
1526 | widget type. When a widget is created, this function is called for the | |
54438eb5 | 1527 | widget type and all the widget's parent types, most derived first. |
6bf7aab6 DL |
1528 | |
1529 | The following predefined functions can be used here: | |
1530 | ||
1531 | @defun widget-types-convert-widget widget | |
1532 | Convert @code{:args} as widget types in @var{widget}. | |
1533 | @end defun | |
1534 | ||
1535 | @defun widget-value-convert-widget widget | |
1536 | Initialize @code{:value} from @code{:args} in @var{widget}. | |
1537 | @end defun | |
1538 | ||
4c2f559e PA |
1539 | @vindex copy@r{ keyword} |
1540 | @item :copy | |
1541 | Function to deep copy a widget type. It takes a shallow copy of the | |
1542 | widget type as an argument (made by @code{copy-sequence}), and returns a | |
1543 | deep copy. The purpose of this is to avoid having different instances | |
1544 | of combined widgets share nested attributes. | |
1545 | ||
1546 | The following predefined functions can be used here: | |
1547 | ||
1548 | @defun widget-types-copy widget | |
1549 | Copy @code{:args} as widget types in @var{widget}. | |
1550 | @end defun | |
1551 | ||
6f7f063d | 1552 | @vindex value-to-internal@r{ keyword} |
6bf7aab6 DL |
1553 | @item :value-to-internal |
1554 | Function to convert the value to the internal format. The function | |
1555 | takes two arguments, a widget and an external value, and returns the | |
1556 | internal value. The function is called on the present @code{:value} | |
1557 | when the widget is created, and on any value set later with | |
1558 | @code{widget-value-set}. | |
1559 | ||
6f7f063d | 1560 | @vindex value-to-external@r{ keyword} |
6bf7aab6 DL |
1561 | @item :value-to-external |
1562 | Function to convert the value to the external format. The function | |
1563 | takes two arguments, a widget and an internal value, and returns the | |
6f7f063d | 1564 | external value. The function is called on the present @code{:value} |
6bf7aab6 DL |
1565 | when the widget is created, and on any value set later with |
1566 | @code{widget-value-set}. | |
1567 | ||
6f7f063d | 1568 | @vindex create@r{ keyword} |
6bf7aab6 DL |
1569 | @item :create |
1570 | Function to create a widget from scratch. The function takes one | |
54438eb5 DL |
1571 | argument, a widget type, and creates a widget of that type, inserts it |
1572 | in the buffer, and returns a widget object. | |
6bf7aab6 | 1573 | |
6f7f063d | 1574 | @vindex delete@r{ keyword} |
6bf7aab6 DL |
1575 | @item :delete |
1576 | Function to delete a widget. The function takes one argument, a widget, | |
1577 | and should remove all traces of the widget from the buffer. | |
1578 | ||
6f7f063d | 1579 | @vindex value-create@r{ keyword} |
6bf7aab6 DL |
1580 | @item :value-create |
1581 | Function to expand the @samp{%v} escape in the format string. It will | |
54438eb5 DL |
1582 | be called with the widget as its argument and should insert a |
1583 | representation of the widget's value in the buffer. | |
6bf7aab6 | 1584 | |
6f7f063d | 1585 | @vindex value-delete@r{ keyword} |
6bf7aab6 | 1586 | @item :value-delete |
54438eb5 | 1587 | Should remove the representation of the widget's value from the buffer. |
6bf7aab6 DL |
1588 | It will be called with the widget as its argument. It doesn't have to |
1589 | remove the text, but it should release markers and delete nested widgets | |
54438eb5 | 1590 | if such have been used. |
6bf7aab6 DL |
1591 | |
1592 | The following predefined function can be used here: | |
1593 | ||
1594 | @defun widget-children-value-delete widget | |
1595 | Delete all @code{:children} and @code{:buttons} in @var{widget}. | |
1596 | @end defun | |
1597 | ||
6f7f063d | 1598 | @vindex value-get@r{ keyword} |
6bf7aab6 DL |
1599 | @item :value-get |
1600 | Function to extract the value of a widget, as it is displayed in the | |
1601 | buffer. | |
1602 | ||
1603 | The following predefined function can be used here: | |
1604 | ||
1605 | @defun widget-value-value-get widget | |
1606 | Return the @code{:value} property of @var{widget}. | |
1607 | @end defun | |
1608 | ||
6f7f063d | 1609 | @vindex format-handler@r{ keyword} |
6bf7aab6 DL |
1610 | @item :format-handler |
1611 | Function to handle unknown @samp{%} escapes in the format string. It | |
6f7f063d EZ |
1612 | will be called with the widget and the character that follows the |
1613 | @samp{%} as arguments. You can set this to allow your widget to handle | |
1614 | non-standard escapes. | |
6bf7aab6 | 1615 | |
6f7f063d | 1616 | @findex widget-default-format-handler |
6bf7aab6 DL |
1617 | You should end up calling @code{widget-default-format-handler} to handle |
1618 | unknown escape sequences, which will handle the @samp{%h} and any future | |
1619 | escape sequences, as well as give an error for unknown escapes. | |
1620 | ||
6f7f063d | 1621 | @vindex action@r{ keyword} |
6bf7aab6 DL |
1622 | @item :action |
1623 | Function to handle user initiated events. By default, @code{:notify} | |
1624 | the parent. | |
1625 | ||
1626 | The following predefined function can be used here: | |
1627 | ||
1628 | @defun widget-parent-action widget &optional event | |
1629 | Tell @code{:parent} of @var{widget} to handle the @code{:action}. | |
1630 | Optional @var{event} is the event that triggered the action. | |
1631 | @end defun | |
1632 | ||
6f7f063d | 1633 | @vindex prompt-value@r{ keyword} |
6bf7aab6 DL |
1634 | @item :prompt-value |
1635 | Function to prompt for a value in the minibuffer. The function should | |
1636 | take four arguments, @var{widget}, @var{prompt}, @var{value}, and | |
1637 | @var{unbound} and should return a value for widget entered by the user. | |
1638 | @var{prompt} is the prompt to use. @var{value} is the default value to | |
54438eb5 | 1639 | use, unless @var{unbound} is non-nil, in which case there is no default |
6bf7aab6 DL |
1640 | value. The function should read the value using the method most natural |
1641 | for this widget, and does not have to check that it matches. | |
1642 | @end table | |
1643 | ||
1644 | If you want to define a new widget from scratch, use the @code{default} | |
1645 | widget as its base. | |
1646 | ||
1647 | @deffn Widget default | |
1648 | Widget used as a base for other widgets. | |
1649 | ||
1650 | It provides most of the functionality that is referred to as ``by | |
1651 | default'' in this text. | |
1652 | @end deffn | |
1653 | ||
1654 | @node Widget Browser, Widget Minor Mode, Defining New Widgets, Top | |
1655 | @comment node-name, next, previous, up | |
1656 | @section Widget Browser | |
6f7f063d | 1657 | @cindex widget browser |
6bf7aab6 DL |
1658 | |
1659 | There is a separate package to browse widgets. This is intended to help | |
1660 | programmers who want to examine the content of a widget. The browser | |
1661 | shows the value of each keyword, but uses links for certain keywords | |
6f7f063d | 1662 | such as @samp{:parent}, which avoids printing cyclic structures. |
6bf7aab6 | 1663 | |
49c24f48 RS |
1664 | @deffn Command widget-browse @var{widget} |
1665 | Create a widget browser for @var{widget}. | |
1666 | When called interactively, prompt for @var{widget}. | |
6bf7aab6 DL |
1667 | @end deffn |
1668 | ||
49c24f48 RS |
1669 | @deffn Command widget-browse-other-window @var{widget} |
1670 | Create a widget browser for @var{widget} and show it in another window. | |
1671 | When called interactively, prompt for @var{widget}. | |
6bf7aab6 DL |
1672 | @end deffn |
1673 | ||
49c24f48 RS |
1674 | @deffn Command widget-browse-at @var{pos} |
1675 | Create a widget browser for the widget at @var{pos}. | |
6bf7aab6 DL |
1676 | When called interactively, use the position of point. |
1677 | @end deffn | |
1678 | ||
1679 | @node Widget Minor Mode, Utilities, Widget Browser, Top | |
1680 | @comment node-name, next, previous, up | |
1681 | @section Widget Minor Mode | |
6f7f063d | 1682 | @cindex widget minor mode |
6bf7aab6 DL |
1683 | |
1684 | There is a minor mode for manipulating widgets in major modes that | |
6f7f063d | 1685 | don't provide any support for widgets themselves. This is mostly |
6bf7aab6 DL |
1686 | intended to be useful for programmers doing experiments. |
1687 | ||
1688 | @deffn Command widget-minor-mode | |
1689 | Toggle minor mode for traversing widgets. | |
1690 | With arg, turn widget mode on if and only if arg is positive. | |
1691 | @end deffn | |
1692 | ||
1693 | @defvar widget-minor-mode-keymap | |
1694 | Keymap used in @code{widget-minor-mode}. | |
1695 | @end defvar | |
1696 | ||
1697 | @node Utilities, Widget Wishlist, Widget Minor Mode, Top | |
1698 | @comment node-name, next, previous, up | |
1699 | @section Utilities. | |
6f7f063d | 1700 | @cindex utility functions for widgets |
6bf7aab6 DL |
1701 | |
1702 | @defun widget-prompt-value widget prompt [ value unbound ] | |
1703 | Prompt for a value matching @var{widget}, using @var{prompt}. | |
1704 | The current value is assumed to be @var{value}, unless @var{unbound} is | |
1705 | non-nil.@refill | |
1706 | @end defun | |
1707 | ||
1708 | @defun widget-get-sibling widget | |
6f7f063d | 1709 | Get the item which @var{widget} is assumed to toggle. |
6bf7aab6 DL |
1710 | This is only meaningful for radio buttons or checkboxes in a list. |
1711 | @end defun | |
1712 | ||
6f7f063d | 1713 | @node Widget Wishlist, Index, Utilities, Top |
6bf7aab6 DL |
1714 | @comment node-name, next, previous, up |
1715 | @section Wishlist | |
6f7f063d | 1716 | @cindex todo |
6bf7aab6 DL |
1717 | |
1718 | @itemize @bullet | |
1719 | @item | |
1720 | It should be possible to add or remove items from a list with @kbd{C-k} | |
1721 | and @kbd{C-o} (suggested by @sc{rms}). | |
1722 | ||
976e00f1 DL |
1723 | @item |
1724 | The @samp{[INS]} and @samp{[DEL]} buttons should be replaced by a single | |
1725 | dash (@samp{-}). The dash should be a button that, when invoked, asks | |
1726 | whether you want to add or delete an item (@sc{rms} wanted to git rid of | |
1727 | the ugly buttons, the dash is my idea). | |
1728 | ||
6bf7aab6 DL |
1729 | @item |
1730 | The @code{menu-choice} tag should be prettier, something like the abbreviated | |
1731 | menus in Open Look. | |
1732 | ||
1733 | @item | |
1734 | Finish @code{:tab-order}. | |
1735 | ||
1736 | @item | |
1737 | Make indentation work with glyphs and proportional fonts. | |
1738 | ||
1739 | @item | |
1740 | Add commands to show overview of object and class hierarchies to the | |
1741 | browser. | |
1742 | ||
1743 | @item | |
1744 | Find a way to disable mouse highlight for inactive widgets. | |
1745 | ||
1746 | @item | |
1747 | Find a way to make glyphs look inactive. | |
1748 | ||
976e00f1 DL |
1749 | @item |
1750 | Add @code{property-list} widget. | |
1751 | ||
1752 | @item | |
1753 | Add @code{association-list} widget. | |
1754 | ||
6bf7aab6 DL |
1755 | @item |
1756 | Add @code{key-binding} widget. | |
1757 | ||
1758 | @item | |
1759 | Add @code{widget} widget for editing widget specifications. | |
1760 | ||
1761 | @item | |
1762 | Find clean way to implement variable length list. | |
1763 | See @code{TeX-printer-list} for an explanation. | |
1764 | ||
1765 | @item | |
1766 | @kbd{C-h} in @code{widget-prompt-value} should give type specific help. | |
1767 | ||
1768 | @item | |
6f7f063d | 1769 | Add a @code{mailto} widget. |
6bf7aab6 DL |
1770 | @end itemize |
1771 | ||
6f7f063d EZ |
1772 | @node Index, , Widget Wishlist, Top |
1773 | @comment node-name, next, previous, up | |
1774 | @unnumbered Index | |
1775 | ||
1776 | This is an alphabetical listing of all concepts, functions, commands, | |
1777 | variables, and widgets described in this manual. | |
1778 | @printindex cp | |
1779 | ||
56f7c94a | 1780 | @setchapternewpage odd |
6bf7aab6 DL |
1781 | @contents |
1782 | @bye |