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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 | |
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13 | Copyright @copyright{} 2000, 2001, 2002, 2003, 2004, 2005, |
14 | 2006, 2007 Free Software Foundation, Inc. | |
a159375d | 15 | |
18f952d5 | 16 | @quotation |
a159375d | 17 | Permission is granted to copy, distribute and/or modify this document |
678e7c71 | 18 | under the terms of the GNU Free Documentation License, Version 1.2 or |
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19 | any later version published by the Free Software Foundation; with the |
20 | Invariant Sections being ``The GNU Manifesto'', ``Distribution'' and | |
21 | ``GNU GENERAL PUBLIC LICENSE'', with the Front-Cover texts being ``A GNU | |
22 | Manual'', and with the Back-Cover Texts as in (a) below. A copy of the | |
23 | license is included in the section entitled ``GNU Free Documentation | |
24 | License'' in the Emacs manual. | |
25 | ||
26 | This document is part of a collection distributed under the GNU Free | |
27 | Documentation License. If you want to distribute this document | |
28 | separately from the collection, you can do so by adding a copy of the | |
29 | license to the document, as described in section 6 of the license. | |
30 | ||
31 | (a) The FSF's Back-Cover Text is: ``You have freedom to copy and modify | |
32 | this GNU Manual, like GNU software. Copies published by the Free | |
33 | Software Foundation raise funds for GNU development.'' | |
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34 | @end quotation |
35 | @end copying | |
6f7f063d | 36 | |
4c2ca4f3 | 37 | @dircategory Emacs |
6bf7aab6 | 38 | @direntry |
a1566793 EZ |
39 | * Widget: (widget). The "widget" package used by the Emacs Customization |
40 | facility. | |
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41 | @end direntry |
42 | ||
43 | @node Top, Introduction, (dir), (dir) | |
44 | @comment node-name, next, previous, up | |
45 | @top The Emacs Widget Library | |
46 | ||
6bf7aab6 | 47 | @menu |
177c0ea7 JB |
48 | * Introduction:: |
49 | * User Interface:: | |
50 | * Programming Example:: | |
51 | * Setting Up the Buffer:: | |
52 | * Basic Types:: | |
53 | * Sexp Types:: | |
54 | * Widget Properties:: | |
55 | * Defining New Widgets:: | |
56 | * Widget Browser:: | |
57 | * Widget Minor Mode:: | |
58 | * Utilities:: | |
59 | * Widget Wishlist:: | |
6f7f063d | 60 | * Index:: |
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61 | @end menu |
62 | ||
63 | @node Introduction, User Interface, Top, Top | |
64 | @comment node-name, next, previous, up | |
65 | @section Introduction | |
66 | ||
ce8abc78 RS |
67 | Most graphical user interface toolkits provide a number of standard |
68 | user interface controls (sometimes known as `widgets' or `gadgets'). | |
69 | Emacs doesn't really support anything like this, except for an | |
70 | incredibly powerful text ``widget.'' On the other hand, Emacs does | |
71 | provide the necessary primitives to implement many other widgets | |
72 | within a text buffer. The @code{widget} package simplifies this task. | |
6bf7aab6 | 73 | |
6f7f063d EZ |
74 | @cindex basic widgets |
75 | @cindex widgets, basic types | |
6bf7aab6 DL |
76 | The basic widgets are: |
77 | ||
78 | @table @code | |
79 | @item link | |
80 | Areas of text with an associated action. Intended for hypertext links | |
81 | embedded in text. | |
177c0ea7 | 82 | @item push-button |
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83 | Like link, but intended for stand-alone buttons. |
84 | @item editable-field | |
85 | An editable text field. It can be either variable or fixed length. | |
86 | @item menu-choice | |
87 | Allows the user to choose one of multiple options from a menu, each | |
88 | option is itself a widget. Only the selected option will be visible in | |
89 | the buffer. | |
90 | @item radio-button-choice | |
91 | Allows the user to choose one of multiple options by activating radio | |
92 | buttons. The options are implemented as widgets. All options will be | |
93 | visible in the buffer. | |
94 | @item item | |
95 | A simple constant widget intended to be used in the @code{menu-choice} and | |
177c0ea7 | 96 | @code{radio-button-choice} widgets. |
6bf7aab6 | 97 | @item choice-item |
6f7f063d | 98 | A button item only intended for use in choices. When invoked, the user |
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99 | will be asked to select another option from the choice widget. |
100 | @item toggle | |
101 | A simple @samp{on}/@samp{off} switch. | |
102 | @item checkbox | |
177c0ea7 | 103 | A checkbox (@samp{[ ]}/@samp{[X]}). |
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104 | @item editable-list |
105 | Create an editable list. The user can insert or delete items in the | |
106 | list. Each list item is itself a widget. | |
107 | @end table | |
108 | ||
6f7f063d | 109 | Now, of what possible use can support for widgets be in a text editor? |
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110 | I'm glad you asked. The answer is that widgets are useful for |
111 | implementing forms. A @dfn{form} in Emacs is a buffer where the user is | |
112 | supposed to fill out a number of fields, each of which has a specific | |
113 | meaning. The user is not supposed to change or delete any of the text | |
114 | between the fields. Examples of forms in Emacs are the @file{forms} | |
115 | package (of course), the customize buffers, the mail and news compose | |
76dd3692 | 116 | modes, and the @acronym{HTML} form support in the @file{w3} browser. |
6bf7aab6 | 117 | |
6f7f063d | 118 | @cindex widget library, why use it |
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119 | The advantages for a programmer of using the @code{widget} package to |
120 | implement forms are: | |
121 | ||
122 | @enumerate | |
123 | @item | |
177c0ea7 | 124 | More complex fields than just editable text are supported. |
6bf7aab6 | 125 | @item |
6f7f063d | 126 | You can give the users immediate feedback if they enter invalid data in a |
6bf7aab6 | 127 | text field, and sometimes prevent entering invalid data. |
177c0ea7 | 128 | @item |
6f7f063d | 129 | You can have fixed sized fields, thus allowing multiple fields to be |
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130 | lined up in columns. |
131 | @item | |
177c0ea7 JB |
132 | It is simple to query or set the value of a field. |
133 | @item | |
6f7f063d | 134 | Editing happens in the buffer, not in the mini-buffer. |
177c0ea7 | 135 | @item |
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136 | Packages using the library get a uniform look, making them easier for |
137 | the user to learn. | |
177c0ea7 | 138 | @item |
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139 | As support for embedded graphics improve, the widget library will be |
140 | extended to use the GUI features. This means that your code using the | |
141 | widget library will also use the new graphic features automatically. | |
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142 | @end enumerate |
143 | ||
d1deeeda | 144 | In order to minimize the code that is loaded by users who do not |
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145 | create any widgets, the code has been split in two files: |
146 | ||
6f7f063d | 147 | @cindex widget library, files |
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148 | @table @file |
149 | @item widget.el | |
150 | This will declare the user variables, define the function | |
177c0ea7 | 151 | @code{define-widget}, and autoload the function @code{widget-create}. |
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152 | @item wid-edit.el |
153 | Everything else is here, there is no reason to load it explicitly, as | |
154 | it will be autoloaded when needed. | |
155 | @end table | |
156 | ||
157 | @node User Interface, Programming Example, Introduction, Top | |
158 | @comment node-name, next, previous, up | |
159 | @section User Interface | |
160 | ||
db71197e | 161 | A form consists of read only text for documentation and some fields, |
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162 | where each field contains two parts, a tag and a value. The tags are |
163 | used to identify the fields, so the documentation can refer to the | |
164 | @samp{foo field}, meaning the field tagged with @samp{Foo}. Here is an | |
165 | example form: | |
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166 | |
167 | @example | |
168 | Here is some documentation. | |
169 | ||
170 | Name: @i{My Name} @strong{Choose}: This option | |
171 | Address: @i{Some Place | |
172 | In some City | |
173 | Some country.} | |
174 | ||
175 | See also @b{_other work_} for more information. | |
176 | ||
177 | Numbers: count to three below | |
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178 | @b{[INS]} @b{[DEL]} @i{One} |
179 | @b{[INS]} @b{[DEL]} @i{Eh, two?} | |
180 | @b{[INS]} @b{[DEL]} @i{Five!} | |
177c0ea7 | 181 | @b{[INS]} |
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182 | |
183 | Select multiple: | |
184 | ||
185 | @b{[X]} This | |
186 | @b{[ ]} That | |
187 | @b{[X]} Thus | |
188 | ||
189 | Select one: | |
190 | ||
191 | @b{(*)} One | |
192 | @b{( )} Another One. | |
193 | @b{( )} A Final One. | |
194 | ||
195 | @b{[Apply Form]} @b{[Reset Form]} | |
196 | @end example | |
197 | ||
db71197e | 198 | The top level widgets in this example are tagged @samp{Name}, |
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199 | @samp{Choose}, @samp{Address}, @samp{_other work_}, @samp{Numbers}, |
200 | @samp{Select multiple}, @samp{Select one}, @samp{[Apply Form]}, and | |
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201 | @samp{[Reset Form]}. There are basically two things the user can do |
202 | within a form, namely editing the editable text fields and activating | |
203 | the buttons. | |
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204 | |
205 | @subsection Editable Text Fields | |
206 | ||
207 | In the example, the value for the @samp{Name} is most likely displayed | |
208 | in an editable text field, and so are values for each of the members of | |
209 | the @samp{Numbers} list. All the normal Emacs editing operations are | |
210 | available for editing these fields. The only restriction is that each | |
211 | change you make must be contained within a single editable text field. | |
212 | For example, capitalizing all text from the middle of one field to the | |
213 | middle of another field is prohibited. | |
214 | ||
4036ed83 PA |
215 | Editable text fields are created by the @code{editable-field} widget. |
216 | ||
8dbc532e LH |
217 | @strong{Warning:} In an @code{editable-field} widget, the editable |
218 | field must not be adjacent to another widget---that won't work. | |
219 | You must put some text in between. Either make this text part of | |
220 | the @code{editable-field} widget itself, or insert it with | |
221 | @code{widget-insert}. | |
222 | ||
223 | The @code{:format} keyword is useful for generating the necessary | |
224 | text; for instance, if you give it a value of @code{"Name: %v "}, | |
225 | the @samp{Name: } part will provide the necessary separating text | |
226 | before the field and the trailing space will provide the | |
227 | separating text after the field. If you don't include the | |
228 | @code{:size} keyword, the field will extend to the end of the | |
229 | line, and the terminating newline will provide separation after. | |
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230 | |
231 | The editing text fields are highlighted with the | |
232 | @code{widget-field-face} face, making them easy to find. | |
233 | ||
234 | @deffn Face widget-field-face | |
235 | Face used for other editing fields. | |
236 | @end deffn | |
237 | ||
238 | @subsection Buttons | |
239 | ||
6f7f063d EZ |
240 | @cindex widget buttons |
241 | @cindex button widgets | |
6bf7aab6 DL |
242 | Some portions of the buffer have an associated @dfn{action}, which can |
243 | be @dfn{invoked} by a standard key or mouse command. These portions | |
244 | are called @dfn{buttons}. The default commands for activating a button | |
245 | are: | |
246 | ||
247 | @table @kbd | |
248 | @item @key{RET} | |
249 | @deffn Command widget-button-press @var{pos} &optional @var{event} | |
250 | Invoke the button at @var{pos}, defaulting to point. | |
251 | If point is not located on a button, invoke the binding in | |
252 | @code{widget-global-map} (by default the global map). | |
253 | @end deffn | |
254 | ||
ce8abc78 RS |
255 | @kindex Mouse-2 @r{(on button widgets}) |
256 | @item Mouse-2 | |
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257 | @deffn Command widget-button-click @var{event} |
258 | Invoke the button at the location of the mouse pointer. If the mouse | |
259 | pointer is located in an editable text field, invoke the binding in | |
260 | @code{widget-global-map} (by default the global map). | |
261 | @end deffn | |
262 | @end table | |
263 | ||
264 | There are several different kind of buttons, all of which are present in | |
265 | the example: | |
266 | ||
267 | @table @emph | |
6f7f063d EZ |
268 | @cindex option field tag |
269 | @item The Option Field Tags | |
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270 | When you invoke one of these buttons, you will be asked to choose |
271 | between a number of different options. This is how you edit an option | |
272 | field. Option fields are created by the @code{menu-choice} widget. In | |
273 | the example, @samp{@b{Choose}} is an option field tag. | |
976e00f1 | 274 | @item The @samp{@b{[INS]}} and @samp{@b{[DEL]}} buttons |
6f7f063d | 275 | Activating these will insert or delete elements from an editable list. |
177c0ea7 | 276 | The list is created by the @code{editable-list} widget. |
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277 | @cindex embedded buttons |
278 | @item Embedded Buttons | |
6bf7aab6 | 279 | The @samp{@b{_other work_}} is an example of an embedded |
db71197e | 280 | button. Embedded buttons are not associated with any fields, but can serve |
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281 | any purpose, such as implementing hypertext references. They are |
282 | usually created by the @code{link} widget. | |
6f7f063d | 283 | @item The @samp{@b{[ ]}} and @samp{@b{[X]}} buttons |
6bf7aab6 | 284 | Activating one of these will convert it to the other. This is useful |
db71197e | 285 | for implementing multiple-choice fields. You can create them with the |
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286 | @code{checkbox} widget. |
287 | @item The @samp{@b{( )}} and @samp{@b{(*)}} buttons | |
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288 | Only one radio button in a @code{radio-button-choice} widget can be |
289 | selected at any time. When you invoke one of the unselected radio | |
290 | buttons, it will be selected and the previous selected radio button will | |
291 | become unselected. | |
db71197e | 292 | @item The @samp{@b{[Apply Form]}} and @samp{@b{[Reset Form]}} buttons |
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293 | These are explicit buttons made with the @code{push-button} widget. The |
294 | main difference from the @code{link} widget is that the buttons will be | |
6bf7aab6 | 295 | displayed as GUI buttons when possible. |
6bf7aab6 DL |
296 | @end table |
297 | ||
177c0ea7 | 298 | To make them easier to locate, buttons are emphasized in the buffer. |
6bf7aab6 DL |
299 | |
300 | @deffn Face widget-button-face | |
301 | Face used for buttons. | |
302 | @end deffn | |
303 | ||
304 | @defopt widget-mouse-face | |
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305 | Face used for highlighting a button when the mouse pointer moves across |
306 | it. | |
6bf7aab6 DL |
307 | @end defopt |
308 | ||
309 | @subsection Navigation | |
310 | ||
311 | You can use all the normal Emacs commands to move around in a form | |
312 | buffer, plus you will have these additional commands: | |
313 | ||
314 | @table @kbd | |
315 | @item @key{TAB} | |
316 | @deffn Command widget-forward &optional count | |
317 | Move point @var{count} buttons or editing fields forward. | |
318 | @end deffn | |
ee6c21a7 | 319 | @item @kbd{M-@key{TAB}} |
feced874 | 320 | @itemx @kbd{S-@key{TAB}} |
6bf7aab6 DL |
321 | @deffn Command widget-backward &optional count |
322 | Move point @var{count} buttons or editing fields backward. | |
323 | @end deffn | |
324 | @end table | |
325 | ||
326 | @node Programming Example, Setting Up the Buffer, User Interface, Top | |
327 | @comment node-name, next, previous, up | |
328 | @section Programming Example | |
329 | ||
6f7f063d EZ |
330 | @cindex widgets, programming example |
331 | @cindex example of using widgets | |
6bf7aab6 DL |
332 | Here is the code to implement the user interface example (@pxref{User |
333 | Interface}). | |
334 | ||
335 | @lisp | |
336 | (require 'widget) | |
337 | ||
338 | (eval-when-compile | |
339 | (require 'wid-edit)) | |
340 | ||
341 | (defvar widget-example-repeat) | |
342 | ||
343 | (defun widget-example () | |
344 | "Create the widgets from the Widget manual." | |
345 | (interactive) | |
346 | (switch-to-buffer "*Widget Example*") | |
347 | (kill-all-local-variables) | |
348 | (make-local-variable 'widget-example-repeat) | |
349 | (let ((inhibit-read-only t)) | |
350 | (erase-buffer)) | |
f24485f1 | 351 | (remove-overlays) |
d9f114a3 | 352 | (widget-insert "Here is some documentation.\n\n") |
6bf7aab6 DL |
353 | (widget-create 'editable-field |
354 | :size 13 | |
d9f114a3 | 355 | :format "Name: %v " ; Text after the field! |
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356 | "My Name") |
357 | (widget-create 'menu-choice | |
358 | :tag "Choose" | |
359 | :value "This" | |
360 | :help-echo "Choose me, please!" | |
361 | :notify (lambda (widget &rest ignore) | |
362 | (message "%s is a good choice!" | |
363 | (widget-value widget))) | |
364 | '(item :tag "This option" :value "This") | |
365 | '(choice-item "That option") | |
366 | '(editable-field :menu-tag "No option" "Thus option")) | |
6bf7aab6 | 367 | (widget-create 'editable-field |
d9f114a3 | 368 | :format "Address: %v" |
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369 | "Some Place\nIn some City\nSome country.") |
370 | (widget-insert "\nSee also ") | |
371 | (widget-create 'link | |
372 | :notify (lambda (&rest ignore) | |
177c0ea7 | 373 | (widget-value-set widget-example-repeat |
6bf7aab6 DL |
374 | '("En" "To" "Tre")) |
375 | (widget-setup)) | |
376 | "other work") | |
177c0ea7 | 377 | (widget-insert |
ec45fa10 | 378 | " for more information.\n\nNumbers: count to three below\n") |
6bf7aab6 DL |
379 | (setq widget-example-repeat |
380 | (widget-create 'editable-list | |
381 | :entry-format "%i %d %v" | |
382 | :notify (lambda (widget &rest ignore) | |
383 | (let ((old (widget-get widget | |
384 | ':example-length)) | |
385 | (new (length (widget-value widget)))) | |
386 | (unless (eq old new) | |
387 | (widget-put widget ':example-length new) | |
388 | (message "You can count to %d." new)))) | |
389 | :value '("One" "Eh, two?" "Five!") | |
390 | '(editable-field :value "three"))) | |
391 | (widget-insert "\n\nSelect multiple:\n\n") | |
392 | (widget-create 'checkbox t) | |
393 | (widget-insert " This\n") | |
394 | (widget-create 'checkbox nil) | |
395 | (widget-insert " That\n") | |
396 | (widget-create 'checkbox | |
397 | :notify (lambda (&rest ignore) (message "Tickle")) | |
398 | t) | |
399 | (widget-insert " Thus\n\nSelect one:\n\n") | |
400 | (widget-create 'radio-button-choice | |
401 | :value "One" | |
402 | :notify (lambda (widget &rest ignore) | |
403 | (message "You selected %s" | |
404 | (widget-value widget))) | |
405 | '(item "One") '(item "Another One.") '(item "A Final One.")) | |
406 | (widget-insert "\n") | |
407 | (widget-create 'push-button | |
177c0ea7 | 408 | :notify (lambda (&rest ignore) |
6bf7aab6 DL |
409 | (if (= (length (widget-value widget-example-repeat)) |
410 | 3) | |
411 | (message "Congratulation!") | |
412 | (error "Three was the count!"))) | |
413 | "Apply Form") | |
414 | (widget-insert " ") | |
415 | (widget-create 'push-button | |
416 | :notify (lambda (&rest ignore) | |
417 | (widget-example)) | |
418 | "Reset Form") | |
419 | (widget-insert "\n") | |
420 | (use-local-map widget-keymap) | |
421 | (widget-setup)) | |
422 | @end lisp | |
423 | ||
424 | @node Setting Up the Buffer, Basic Types, Programming Example, Top | |
425 | @comment node-name, next, previous, up | |
426 | @section Setting Up the Buffer | |
427 | ||
428 | Widgets are created with @code{widget-create}, which returns a | |
429 | @dfn{widget} object. This object can be queried and manipulated by | |
430 | other widget functions, until it is deleted with @code{widget-delete}. | |
431 | After the widgets have been created, @code{widget-setup} must be called | |
432 | to enable them. | |
433 | ||
434 | @defun widget-create type [ keyword argument ]@dots{} | |
435 | Create and return a widget of type @var{type}. | |
436 | The syntax for the @var{type} argument is described in @ref{Basic Types}. | |
437 | ||
438 | The keyword arguments can be used to overwrite the keyword arguments | |
439 | that are part of @var{type}. | |
440 | @end defun | |
441 | ||
442 | @defun widget-delete widget | |
443 | Delete @var{widget} and remove it from the buffer. | |
444 | @end defun | |
445 | ||
177c0ea7 JB |
446 | @defun widget-setup |
447 | Set up a buffer to support widgets. | |
6bf7aab6 DL |
448 | |
449 | This should be called after creating all the widgets and before allowing | |
450 | the user to edit them. | |
451 | @refill | |
452 | @end defun | |
453 | ||
454 | If you want to insert text outside the widgets in the form, the | |
455 | recommended way to do that is with @code{widget-insert}. | |
456 | ||
177c0ea7 | 457 | @defun widget-insert |
6bf7aab6 | 458 | Insert the arguments, either strings or characters, at point. |
6f7f063d | 459 | The inserted text will be read-only. |
6bf7aab6 DL |
460 | @end defun |
461 | ||
462 | There is a standard widget keymap which you might find useful. | |
463 | ||
6f7f063d EZ |
464 | @findex widget-button-press |
465 | @findex widget-button-click | |
6bf7aab6 DL |
466 | @defvr Const widget-keymap |
467 | A keymap with the global keymap as its parent.@* | |
468 | @key{TAB} and @kbd{C-@key{TAB}} are bound to @code{widget-forward} and | |
ce8abc78 | 469 | @code{widget-backward}, respectively. @key{RET} and @kbd{Mouse-2} |
6bf7aab6 | 470 | are bound to @code{widget-button-press} and |
6f7f063d | 471 | @code{widget-button-click}.@refill |
6bf7aab6 DL |
472 | @end defvr |
473 | ||
474 | @defvar widget-global-map | |
475 | Keymap used by @code{widget-button-press} and @code{widget-button-click} | |
476 | when not on a button. By default this is @code{global-map}. | |
477 | @end defvar | |
478 | ||
479 | @node Basic Types, Sexp Types, Setting Up the Buffer, Top | |
480 | @comment node-name, next, previous, up | |
481 | @section Basic Types | |
482 | ||
87171118 | 483 | This is the general syntax of a type specification: |
6bf7aab6 DL |
484 | |
485 | @example | |
87171118 RS |
486 | @var{name} ::= (@var{name} [@var{keyword} @var{argument}]... @var{args}) |
487 | | @var{name} | |
6bf7aab6 DL |
488 | @end example |
489 | ||
490 | Where, @var{name} is a widget name, @var{keyword} is the name of a | |
491 | property, @var{argument} is the value of the property, and @var{args} | |
492 | are interpreted in a widget specific way. | |
493 | ||
6f7f063d | 494 | @cindex keyword arguments |
db71197e | 495 | The following keyword arguments apply to all widgets: |
6bf7aab6 DL |
496 | |
497 | @table @code | |
6f7f063d | 498 | @vindex value@r{ keyword} |
6bf7aab6 DL |
499 | @item :value |
500 | The initial value for widgets of this type. | |
501 | ||
6f7f063d | 502 | @vindex format@r{ keyword} |
6bf7aab6 DL |
503 | @item :format |
504 | This string will be inserted in the buffer when you create a widget. | |
505 | The following @samp{%} escapes are available: | |
506 | ||
507 | @table @samp | |
508 | @item %[ | |
509 | @itemx %] | |
510 | The text inside will be marked as a button. | |
511 | ||
512 | By default, the text will be shown in @code{widget-button-face}, and | |
177c0ea7 | 513 | surrounded by brackets. |
6bf7aab6 DL |
514 | |
515 | @defopt widget-button-prefix | |
516 | String to prefix buttons. | |
517 | @end defopt | |
518 | ||
519 | @defopt widget-button-suffix | |
520 | String to suffix buttons. | |
521 | @end defopt | |
522 | ||
523 | @item %@{ | |
524 | @itemx %@} | |
525 | The text inside will be displayed with the face specified by | |
177c0ea7 | 526 | @code{:sample-face}. |
6bf7aab6 DL |
527 | |
528 | @item %v | |
54438eb5 | 529 | This will be replaced with the buffer representation of the widget's |
6bf7aab6 DL |
530 | value. What this is depends on the widget type. |
531 | ||
532 | @item %d | |
533 | Insert the string specified by @code{:doc} here. | |
534 | ||
535 | @item %h | |
536 | Like @samp{%d}, with the following modifications: If the documentation | |
537 | string is more than one line, it will add a button which will toggle | |
538 | between showing only the first line, and showing the full text. | |
539 | Furthermore, if there is no @code{:doc} property in the widget, it will | |
540 | instead examine the @code{:documentation-property} property. If it is a | |
541 | lambda expression, it will be called with the widget's value as an | |
542 | argument, and the result will be used as the documentation text. | |
543 | ||
544 | @item %t | |
545 | Insert the string specified by @code{:tag} here, or the @code{princ} | |
546 | representation of the value if there is no tag. | |
547 | ||
548 | @item %% | |
177c0ea7 | 549 | Insert a literal @samp{%}. |
6bf7aab6 DL |
550 | @end table |
551 | ||
6f7f063d | 552 | @vindex button-face@r{ keyword} |
6bf7aab6 DL |
553 | @item :button-face |
554 | Face used to highlight text inside %[ %] in the format. | |
555 | ||
6f7f063d EZ |
556 | @vindex button-prefix@r{ keyword} |
557 | @vindex button-suffix@r{ keyword} | |
6bf7aab6 DL |
558 | @item :button-prefix |
559 | @itemx :button-suffix | |
6bf7aab6 DL |
560 | Text around %[ %] in the format. |
561 | ||
562 | These can be | |
563 | @table @emph | |
564 | @item nil | |
565 | No text is inserted. | |
566 | ||
567 | @item a string | |
568 | The string is inserted literally. | |
569 | ||
570 | @item a symbol | |
571 | The value of the symbol is expanded according to this table. | |
572 | @end table | |
573 | ||
6f7f063d | 574 | @vindex doc@r{ keyword} |
6bf7aab6 DL |
575 | @item :doc |
576 | The string inserted by the @samp{%d} escape in the format | |
177c0ea7 | 577 | string. |
6bf7aab6 | 578 | |
6f7f063d | 579 | @vindex tag@r{ keyword} |
6bf7aab6 DL |
580 | @item :tag |
581 | The string inserted by the @samp{%t} escape in the format | |
177c0ea7 | 582 | string. |
6bf7aab6 | 583 | |
6f7f063d | 584 | @vindex tag-glyph@r{ keyword} |
6bf7aab6 | 585 | @item :tag-glyph |
6f7f063d | 586 | Name of image to use instead of the string specified by @code{:tag} on |
6bf7aab6 DL |
587 | Emacsen that supports it. |
588 | ||
6f7f063d | 589 | @vindex help-echo@r{ keyword} |
6bf7aab6 | 590 | @item :help-echo |
a159375d DL |
591 | Specifies how to display a message whenever you move to the widget with |
592 | either @code{widget-forward} or @code{widget-backward} or move the mouse | |
56600dfa | 593 | over it (using the standard @code{help-echo} mechanism). The argument |
b0ab008b LT |
594 | is either a string to display, a function of one argument, the widget, |
595 | which should return a string to display, or a form that evaluates to | |
596 | such a string. | |
6bf7aab6 | 597 | |
d3ceff91 KS |
598 | @vindex follow-link@r{ keyword} |
599 | @item :follow-link | |
600 | Specifies how to interpret a @key{mouse-1} click on the widget. | |
1fd0f7a6 | 601 | @xref{Links and Mouse-1,,, elisp, the Emacs Lisp Reference Manual}. |
d3ceff91 | 602 | |
6f7f063d | 603 | @vindex indent@r{ keyword} |
6bf7aab6 DL |
604 | @item :indent |
605 | An integer indicating the absolute number of spaces to indent children | |
606 | of this widget. | |
607 | ||
6f7f063d | 608 | @vindex offset@r{ keyword} |
6bf7aab6 DL |
609 | @item :offset |
610 | An integer indicating how many extra spaces to add to the widget's | |
611 | grandchildren compared to this widget. | |
612 | ||
6f7f063d | 613 | @vindex extra-offset@r{ keyword} |
6bf7aab6 DL |
614 | @item :extra-offset |
615 | An integer indicating how many extra spaces to add to the widget's | |
616 | children compared to this widget. | |
617 | ||
6f7f063d | 618 | @vindex notify@r{ keyword} |
6bf7aab6 DL |
619 | @item :notify |
620 | A function called each time the widget or a nested widget is changed. | |
621 | The function is called with two or three arguments. The first argument | |
622 | is the widget itself, the second argument is the widget that was | |
623 | changed, and the third argument is the event leading to the change, if | |
177c0ea7 | 624 | any. |
6bf7aab6 | 625 | |
6f7f063d | 626 | @vindex menu-tag@r{ keyword} |
6bf7aab6 DL |
627 | @item :menu-tag |
628 | Tag used in the menu when the widget is used as an option in a | |
629 | @code{menu-choice} widget. | |
630 | ||
6f7f063d | 631 | @vindex menu-tag-get@r{ keyword} |
6bf7aab6 DL |
632 | @item :menu-tag-get |
633 | Function used for finding the tag when the widget is used as an option | |
634 | in a @code{menu-choice} widget. By default, the tag used will be either the | |
635 | @code{:menu-tag} or @code{:tag} property if present, or the @code{princ} | |
636 | representation of the @code{:value} property if not. | |
637 | ||
6f7f063d | 638 | @vindex match@r{ keyword} |
6bf7aab6 DL |
639 | @item :match |
640 | Should be a function called with two arguments, the widget and a value, | |
65247564 | 641 | and returning non-@code{nil} if the widget can represent the specified value. |
6bf7aab6 | 642 | |
6f7f063d | 643 | @vindex validate@r{ keyword} |
6bf7aab6 | 644 | @item :validate |
6f7f063d EZ |
645 | A function which takes a widget as an argument, and returns @code{nil} |
646 | if the widget's current value is valid for the widget. Otherwise it | |
647 | should return the widget containing the invalid data, and set that | |
648 | widget's @code{:error} property to a string explaining the error. | |
6bf7aab6 DL |
649 | |
650 | The following predefined function can be used: | |
651 | ||
652 | @defun widget-children-validate widget | |
653 | All the @code{:children} of @var{widget} must be valid. | |
654 | @end defun | |
655 | ||
6f7f063d | 656 | @vindex tab-order@r{ keyword} |
6bf7aab6 DL |
657 | @item :tab-order |
658 | Specify the order in which widgets are traversed with | |
659 | @code{widget-forward} or @code{widget-backward}. This is only partially | |
660 | implemented. | |
661 | ||
662 | @enumerate a | |
663 | @item | |
664 | Widgets with tabbing order @code{-1} are ignored. | |
665 | ||
177c0ea7 | 666 | @item |
6bf7aab6 DL |
667 | (Unimplemented) When on a widget with tabbing order @var{n}, go to the |
668 | next widget in the buffer with tabbing order @var{n+1} or @code{nil}, | |
669 | whichever comes first. | |
670 | ||
671 | @item | |
672 | When on a widget with no tabbing order specified, go to the next widget | |
673 | in the buffer with a positive tabbing order, or @code{nil} | |
674 | @end enumerate | |
675 | ||
6f7f063d | 676 | @vindex parent@r{ keyword} |
6bf7aab6 | 677 | @item :parent |
a159375d | 678 | The parent of a nested widget (e.g.@: a @code{menu-choice} item or an |
6bf7aab6 DL |
679 | element of a @code{editable-list} widget). |
680 | ||
6f7f063d | 681 | @vindex sibling-args@r{ keyword} |
6bf7aab6 DL |
682 | @item :sibling-args |
683 | This keyword is only used for members of a @code{radio-button-choice} or | |
684 | @code{checklist}. The value should be a list of extra keyword | |
685 | arguments, which will be used when creating the @code{radio-button} or | |
686 | @code{checkbox} associated with this item. | |
687 | ||
688 | @end table | |
689 | ||
690 | @deffn {User Option} widget-glyph-directory | |
177c0ea7 | 691 | Directory where glyphs are found. |
6bf7aab6 | 692 | Widget will look here for a file with the same name as specified for the |
6f7f063d | 693 | image, with either a @file{.xpm} (if supported) or @file{.xbm} extension. |
6bf7aab6 DL |
694 | @end deffn |
695 | ||
696 | @deffn{User Option} widget-glyph-enable | |
9995b954 | 697 | If non-@code{nil}, allow glyphs to appear on displays where they are supported. |
6bf7aab6 DL |
698 | @end deffn |
699 | ||
700 | ||
701 | @menu | |
177c0ea7 JB |
702 | * link:: |
703 | * url-link:: | |
704 | * info-link:: | |
705 | * push-button:: | |
706 | * editable-field:: | |
707 | * text:: | |
708 | * menu-choice:: | |
709 | * radio-button-choice:: | |
710 | * item:: | |
711 | * choice-item:: | |
712 | * toggle:: | |
713 | * checkbox:: | |
714 | * checklist:: | |
715 | * editable-list:: | |
716 | * group:: | |
6bf7aab6 DL |
717 | @end menu |
718 | ||
719 | @node link, url-link, Basic Types, Basic Types | |
720 | @comment node-name, next, previous, up | |
721 | @subsection The @code{link} Widget | |
6f7f063d | 722 | @findex link@r{ widget} |
6bf7aab6 DL |
723 | |
724 | Syntax: | |
725 | ||
726 | @example | |
87171118 | 727 | @var{type} ::= (link [@var{keyword} @var{argument}]... [ @var{value} ]) |
6bf7aab6 DL |
728 | @end example |
729 | ||
730 | The @var{value}, if present, is used to initialize the @code{:value} | |
731 | property. The value should be a string, which will be inserted in the | |
177c0ea7 | 732 | buffer. |
6bf7aab6 DL |
733 | |
734 | By default the link will be shown in brackets. | |
735 | ||
736 | @defopt widget-link-prefix | |
737 | String to prefix links. | |
738 | @end defopt | |
739 | ||
740 | @defopt widget-link-suffix | |
741 | String to suffix links. | |
742 | @end defopt | |
743 | ||
744 | @node url-link, info-link, link, Basic Types | |
745 | @comment node-name, next, previous, up | |
746 | @subsection The @code{url-link} Widget | |
6f7f063d | 747 | @findex url-link@r{ widget} |
6bf7aab6 DL |
748 | |
749 | Syntax: | |
750 | ||
751 | @example | |
87171118 | 752 | @var{type} ::= (url-link [@var{keyword} @var{argument}]... @var{url}) |
6bf7aab6 DL |
753 | @end example |
754 | ||
6f7f063d | 755 | @findex browse-url-browser-function@r{, and @code{url-link} widget} |
76dd3692 | 756 | When this link is invoked, the @acronym{WWW} browser specified by |
177c0ea7 | 757 | @code{browse-url-browser-function} will be called with @var{url}. |
6bf7aab6 DL |
758 | |
759 | @node info-link, push-button, url-link, Basic Types | |
760 | @comment node-name, next, previous, up | |
761 | @subsection The @code{info-link} Widget | |
6f7f063d | 762 | @findex info-link@r{ widget} |
6bf7aab6 DL |
763 | |
764 | Syntax: | |
765 | ||
766 | @example | |
87171118 | 767 | @var{type} ::= (info-link [@var{keyword} @var{argument}]... @var{address}) |
6bf7aab6 DL |
768 | @end example |
769 | ||
6f7f063d | 770 | When this link is invoked, the built-in Info reader is started on |
177c0ea7 | 771 | @var{address}. |
6bf7aab6 DL |
772 | |
773 | @node push-button, editable-field, info-link, Basic Types | |
774 | @comment node-name, next, previous, up | |
775 | @subsection The @code{push-button} Widget | |
6f7f063d | 776 | @findex push-button@r{ widget} |
6bf7aab6 DL |
777 | |
778 | Syntax: | |
779 | ||
780 | @example | |
87171118 | 781 | @var{type} ::= (push-button [@var{keyword} @var{argument}]... [ @var{value} ]) |
6bf7aab6 DL |
782 | @end example |
783 | ||
784 | The @var{value}, if present, is used to initialize the @code{:value} | |
6f7f063d | 785 | property. The value should be a string, which will be inserted in the |
177c0ea7 | 786 | buffer. |
6bf7aab6 DL |
787 | |
788 | By default the tag will be shown in brackets. | |
789 | ||
790 | @defopt widget-push-button-prefix | |
791 | String to prefix push buttons. | |
792 | @end defopt | |
793 | ||
794 | @defopt widget-push-button-suffix | |
795 | String to suffix push buttons. | |
796 | @end defopt | |
797 | ||
798 | @node editable-field, text, push-button, Basic Types | |
799 | @comment node-name, next, previous, up | |
800 | @subsection The @code{editable-field} Widget | |
6f7f063d | 801 | @findex editable-field@r{ widget} |
6bf7aab6 DL |
802 | |
803 | Syntax: | |
804 | ||
805 | @example | |
87171118 | 806 | @var{type} ::= (editable-field [@var{keyword} @var{argument}]... [ @var{value} ]) |
6bf7aab6 DL |
807 | @end example |
808 | ||
809 | The @var{value}, if present, is used to initialize the @code{:value} | |
db71197e | 810 | property. The value should be a string, which will be inserted in the |
6bf7aab6 DL |
811 | field. This widget will match all string values. |
812 | ||
6f7f063d | 813 | The following extra properties are recognized: |
6bf7aab6 DL |
814 | |
815 | @table @code | |
6f7f063d | 816 | @vindex size@r{ keyword} |
6bf7aab6 DL |
817 | @item :size |
818 | The width of the editable field.@* | |
819 | By default the field will reach to the end of the line. | |
820 | ||
6f7f063d | 821 | @vindex value-face@r{ keyword} |
6bf7aab6 DL |
822 | @item :value-face |
823 | Face used for highlighting the editable field. Default is | |
177c0ea7 | 824 | @code{widget-field-face}, see @ref{User Interface}. |
6bf7aab6 | 825 | |
6f7f063d | 826 | @vindex secret@r{ keyword} |
6bf7aab6 | 827 | @item :secret |
a159375d | 828 | Character used to display the value. You can set this to e.g.@: @code{?*} |
6bf7aab6 | 829 | if the field contains a password or other secret information. By |
9995b954 | 830 | default, this is @code{nil}, and the value is not secret. |
6bf7aab6 | 831 | |
6f7f063d | 832 | @vindex valid-regexp@r{ keyword} |
6bf7aab6 DL |
833 | @item :valid-regexp |
834 | By default the @code{:validate} function will match the content of the | |
835 | field with the value of this attribute. The default value is @code{""} | |
836 | which matches everything. | |
837 | ||
6f7f063d EZ |
838 | @vindex keymap@r{ keyword} |
839 | @vindex widget-field-keymap | |
6bf7aab6 DL |
840 | @item :keymap |
841 | Keymap used in the editable field. The default value is | |
842 | @code{widget-field-keymap}, which allows you to use all the normal | |
6f7f063d EZ |
843 | editing commands, even if the buffer's major mode suppresses some of |
844 | them. Pressing @key{RET} invokes the function specified by | |
845 | @code{:action}. | |
6bf7aab6 DL |
846 | @end table |
847 | ||
848 | @node text, menu-choice, editable-field, Basic Types | |
849 | @comment node-name, next, previous, up | |
850 | @subsection The @code{text} Widget | |
6f7f063d | 851 | @findex text@r{ widget} |
6bf7aab6 | 852 | |
6f7f063d | 853 | @vindex widget-text-keymap |
6bf7aab6 DL |
854 | This is just like @code{editable-field}, but intended for multiline text |
855 | fields. The default @code{:keymap} is @code{widget-text-keymap}, which | |
6f7f063d | 856 | does not rebind the @key{RET} key. |
6bf7aab6 DL |
857 | |
858 | @node menu-choice, radio-button-choice, text, Basic Types | |
859 | @comment node-name, next, previous, up | |
860 | @subsection The @code{menu-choice} Widget | |
6f7f063d | 861 | @findex menu-choice@r{ widget} |
6bf7aab6 DL |
862 | |
863 | Syntax: | |
864 | ||
865 | @example | |
87171118 | 866 | @var{type} ::= (menu-choice [@var{keyword} @var{argument}]... @var{type} ... ) |
6bf7aab6 DL |
867 | @end example |
868 | ||
54438eb5 DL |
869 | The @var{type} argument represents each possible choice. The widget's |
870 | value will be that of the chosen @var{type} argument. This widget will | |
871 | match any value matching at least one of the specified @var{type} | |
872 | arguments. | |
6bf7aab6 DL |
873 | |
874 | @table @code | |
6f7f063d | 875 | @vindex void@r{ keyword} |
177c0ea7 | 876 | @item :void |
6bf7aab6 DL |
877 | Widget type used as a fallback when the value does not match any of the |
878 | specified @var{type} arguments. | |
879 | ||
6f7f063d | 880 | @vindex case-fold@r{ keyword} |
6bf7aab6 | 881 | @item :case-fold |
9995b954 | 882 | Set this to @code{nil} if you don't want to ignore case when prompting for a |
6bf7aab6 DL |
883 | choice through the minibuffer. |
884 | ||
6f7f063d | 885 | @vindex children@r{ keyword} |
6bf7aab6 | 886 | @item :children |
9995b954 | 887 | A list whose @sc{car} is the widget representing the currently chosen |
6f7f063d | 888 | type in the buffer. |
6bf7aab6 | 889 | |
6f7f063d | 890 | @vindex choice@r{ keyword} |
6bf7aab6 | 891 | @item :choice |
6f7f063d | 892 | The current chosen type. |
6bf7aab6 | 893 | |
6f7f063d | 894 | @vindex args@r{ keyword} |
177c0ea7 JB |
895 | @item :args |
896 | The list of types. | |
6bf7aab6 DL |
897 | @end table |
898 | ||
899 | @node radio-button-choice, item, menu-choice, Basic Types | |
900 | @comment node-name, next, previous, up | |
901 | @subsection The @code{radio-button-choice} Widget | |
6f7f063d | 902 | @findex radio-button-choice@r{ widget} |
6bf7aab6 DL |
903 | |
904 | Syntax: | |
905 | ||
906 | @example | |
87171118 | 907 | @var{type} ::= (radio-button-choice [@var{keyword} @var{argument}]... @var{type} ... ) |
6bf7aab6 DL |
908 | @end example |
909 | ||
87171118 RS |
910 | The component types specify the choices, with one radio button for |
911 | each. The widget's value will be that of the chosen @var{type} | |
7da31552 | 912 | argument. This widget matches any value that matches at least one of |
87171118 | 913 | the specified @var{type} arguments. |
6bf7aab6 DL |
914 | |
915 | The following extra properties are recognized. | |
916 | ||
917 | @table @code | |
6f7f063d | 918 | @vindex entry-format@r{ keyword} |
6bf7aab6 DL |
919 | @item :entry-format |
920 | This string will be inserted for each entry in the list. | |
921 | The following @samp{%} escapes are available: | |
922 | @table @samp | |
923 | @item %v | |
6f7f063d | 924 | Replace with the buffer representation of the @var{type} widget. |
6bf7aab6 DL |
925 | @item %b |
926 | Replace with the radio button. | |
927 | @item %% | |
177c0ea7 | 928 | Insert a literal @samp{%}. |
6bf7aab6 DL |
929 | @end table |
930 | ||
6f7f063d EZ |
931 | @vindex button-args@r{ keyword} |
932 | @item :button-args | |
6bf7aab6 | 933 | A list of keywords to pass to the radio buttons. Useful for setting |
a159375d | 934 | e.g.@: the @samp{:help-echo} for each button. |
6bf7aab6 | 935 | |
6f7f063d | 936 | @vindex buttons@r{ keyword} |
6bf7aab6 DL |
937 | @item :buttons |
938 | The widgets representing the radio buttons. | |
939 | ||
6f7f063d | 940 | @vindex children@r{ keyword} |
6bf7aab6 DL |
941 | @item :children |
942 | The widgets representing each type. | |
943 | ||
6f7f063d | 944 | @vindex choice@r{ keyword} |
6bf7aab6 DL |
945 | @item :choice |
946 | The current chosen type | |
947 | ||
6f7f063d | 948 | @vindex args@r{ keyword} |
177c0ea7 JB |
949 | @item :args |
950 | The list of types. | |
6bf7aab6 DL |
951 | @end table |
952 | ||
953 | You can add extra radio button items to a @code{radio-button-choice} | |
954 | widget after it has been created with the function | |
177c0ea7 | 955 | @code{widget-radio-add-item}. |
6bf7aab6 DL |
956 | |
957 | @defun widget-radio-add-item widget type | |
6f7f063d EZ |
958 | Add to @code{radio-button-choice} widget @var{widget} a new radio button |
959 | item of type @var{type}. | |
6bf7aab6 DL |
960 | @end defun |
961 | ||
962 | Please note that such items added after the @code{radio-button-choice} | |
963 | widget has been created will @strong{not} be properly destructed when | |
964 | you call @code{widget-delete}. | |
965 | ||
966 | @node item, choice-item, radio-button-choice, Basic Types | |
967 | @comment node-name, next, previous, up | |
968 | @subsection The @code{item} Widget | |
6f7f063d | 969 | @findex item@r{ widget} |
6bf7aab6 DL |
970 | |
971 | Syntax: | |
972 | ||
973 | @example | |
87171118 | 974 | @var{item} ::= (item [@var{keyword} @var{argument}]... @var{value}) |
6bf7aab6 DL |
975 | @end example |
976 | ||
977 | The @var{value}, if present, is used to initialize the @code{:value} | |
978 | property. The value should be a string, which will be inserted in the | |
979 | buffer. This widget will only match the specified value. | |
980 | ||
981 | @node choice-item, toggle, item, Basic Types | |
982 | @comment node-name, next, previous, up | |
983 | @subsection The @code{choice-item} Widget | |
6f7f063d | 984 | @findex choice-item@r{ widget} |
6bf7aab6 DL |
985 | |
986 | Syntax: | |
987 | ||
988 | @example | |
87171118 | 989 | @var{item} ::= (choice-item [@var{keyword} @var{argument}]... @var{value}) |
6bf7aab6 DL |
990 | @end example |
991 | ||
992 | The @var{value}, if present, is used to initialize the @code{:value} | |
993 | property. The value should be a string, which will be inserted in the | |
994 | buffer as a button. Activating the button of a @code{choice-item} is | |
995 | equivalent to activating the parent widget. This widget will only match | |
177c0ea7 | 996 | the specified value. |
6bf7aab6 DL |
997 | |
998 | @node toggle, checkbox, choice-item, Basic Types | |
999 | @comment node-name, next, previous, up | |
1000 | @subsection The @code{toggle} Widget | |
6f7f063d | 1001 | @findex toggle@r{ widget} |
6bf7aab6 DL |
1002 | |
1003 | Syntax: | |
1004 | ||
1005 | @example | |
87171118 | 1006 | @var{type} ::= (toggle [@var{keyword} @var{argument}]...) |
6bf7aab6 DL |
1007 | @end example |
1008 | ||
6f7f063d EZ |
1009 | The widget has two possible states, @samp{on} and @samp{off}, which |
1010 | correspond to a @code{t} or @code{nil} value, respectively. | |
6bf7aab6 | 1011 | |
6f7f063d | 1012 | The following extra properties are recognized: |
6bf7aab6 DL |
1013 | |
1014 | @table @code | |
1015 | @item :on | |
6f7f063d EZ |
1016 | A string representing the @samp{on} state. By default the string |
1017 | @samp{on}. | |
177c0ea7 | 1018 | @item :off |
6f7f063d EZ |
1019 | A string representing the @samp{off} state. By default the string |
1020 | @samp{off}. | |
1021 | @vindex on-glyph@r{ keyword} | |
6bf7aab6 | 1022 | @item :on-glyph |
6f7f063d EZ |
1023 | Name of a glyph to be used instead of the @samp{:on} text string, on |
1024 | emacsen that supports this. | |
1025 | @vindex off-glyph@r{ keyword} | |
6bf7aab6 | 1026 | @item :off-glyph |
6f7f063d EZ |
1027 | Name of a glyph to be used instead of the @samp{:off} text string, on |
1028 | emacsen that supports this. | |
6bf7aab6 DL |
1029 | @end table |
1030 | ||
1031 | @node checkbox, checklist, toggle, Basic Types | |
1032 | @comment node-name, next, previous, up | |
1033 | @subsection The @code{checkbox} Widget | |
6f7f063d | 1034 | @findex checkbox@r{ widget} |
6bf7aab6 | 1035 | |
6f7f063d EZ |
1036 | This widget has two possible states, @samp{selected} and |
1037 | @samp{unselected}, which corresponds to a @code{t} or @code{nil} value. | |
6bf7aab6 DL |
1038 | |
1039 | Syntax: | |
1040 | ||
1041 | @example | |
87171118 | 1042 | @var{type} ::= (checkbox [@var{keyword} @var{argument}]...) |
6bf7aab6 DL |
1043 | @end example |
1044 | ||
1045 | @node checklist, editable-list, checkbox, Basic Types | |
1046 | @comment node-name, next, previous, up | |
1047 | @subsection The @code{checklist} Widget | |
6f7f063d | 1048 | @findex checklist@r{ widget} |
6bf7aab6 DL |
1049 | |
1050 | Syntax: | |
1051 | ||
1052 | @example | |
87171118 | 1053 | @var{type} ::= (checklist [@var{keyword} @var{argument}]... @var{type} ... ) |
6bf7aab6 DL |
1054 | @end example |
1055 | ||
6f7f063d EZ |
1056 | The @var{type} arguments represent each checklist item. The widget's |
1057 | value will be a list containing the values of all checked @var{type} | |
54438eb5 DL |
1058 | arguments. The checklist widget will match a list whose elements all |
1059 | match at least one of the specified @var{type} arguments. | |
6bf7aab6 | 1060 | |
6f7f063d | 1061 | The following extra properties are recognized: |
6bf7aab6 DL |
1062 | |
1063 | @table @code | |
6f7f063d | 1064 | @vindex entry-format@r{ keyword} |
6bf7aab6 DL |
1065 | @item :entry-format |
1066 | This string will be inserted for each entry in the list. | |
1067 | The following @samp{%} escapes are available: | |
1068 | @table @samp | |
1069 | @item %v | |
1070 | Replaced with the buffer representation of the @var{type} widget. | |
1071 | @item %b | |
1072 | Replace with the checkbox. | |
1073 | @item %% | |
177c0ea7 | 1074 | Insert a literal @samp{%}. |
6bf7aab6 DL |
1075 | @end table |
1076 | ||
6f7f063d | 1077 | @vindex greedy@r{ keyword} |
6bf7aab6 | 1078 | @item :greedy |
54438eb5 | 1079 | Usually a checklist will only match if the items are in the exact |
6bf7aab6 | 1080 | sequence given in the specification. By setting @code{:greedy} to |
9995b954 JH |
1081 | non-@code{nil}, it will allow the items to come in any sequence. |
1082 | However, if you extract the value they will be in the sequence given | |
1083 | in the checklist, i.e.@: the original sequence is forgotten. | |
6bf7aab6 | 1084 | |
6f7f063d | 1085 | @vindex button-args@r{ keyword} |
a159375d | 1086 | @item :button-args |
6bf7aab6 | 1087 | A list of keywords to pass to the checkboxes. Useful for setting |
a159375d | 1088 | e.g.@: the @samp{:help-echo} for each checkbox. |
6bf7aab6 | 1089 | |
6f7f063d | 1090 | @vindex buttons@r{ keyword} |
6bf7aab6 DL |
1091 | @item :buttons |
1092 | The widgets representing the checkboxes. | |
1093 | ||
6f7f063d | 1094 | @vindex children@r{ keyword} |
6bf7aab6 DL |
1095 | @item :children |
1096 | The widgets representing each type. | |
1097 | ||
6f7f063d | 1098 | @vindex args@r{ keyword} |
177c0ea7 JB |
1099 | @item :args |
1100 | The list of types. | |
6bf7aab6 DL |
1101 | @end table |
1102 | ||
1103 | @node editable-list, group, checklist, Basic Types | |
1104 | @comment node-name, next, previous, up | |
1105 | @subsection The @code{editable-list} Widget | |
6f7f063d | 1106 | @findex editable-list@r{ widget} |
6bf7aab6 DL |
1107 | |
1108 | Syntax: | |
1109 | ||
1110 | @example | |
87171118 | 1111 | @var{type} ::= (editable-list [@var{keyword} @var{argument}]... @var{type}) |
6bf7aab6 DL |
1112 | @end example |
1113 | ||
1114 | The value is a list, where each member represents one widget of type | |
177c0ea7 | 1115 | @var{type}. |
6bf7aab6 | 1116 | |
6f7f063d | 1117 | The following extra properties are recognized: |
6bf7aab6 DL |
1118 | |
1119 | @table @code | |
6f7f063d | 1120 | @vindex entry-format@r{ keyword} |
6bf7aab6 DL |
1121 | @item :entry-format |
1122 | This string will be inserted for each entry in the list. | |
1123 | The following @samp{%} escapes are available: | |
1124 | @table @samp | |
1125 | @item %v | |
1126 | This will be replaced with the buffer representation of the @var{type} | |
1127 | widget. | |
1128 | @item %i | |
976e00f1 | 1129 | Insert the @b{[INS]} button. |
6bf7aab6 DL |
1130 | @item %d |
1131 | Insert the @b{[DEL]} button. | |
1132 | @item %% | |
177c0ea7 | 1133 | Insert a literal @samp{%}. |
6bf7aab6 DL |
1134 | @end table |
1135 | ||
976e00f1 DL |
1136 | @vindex insert-button-args@r{ keyword} |
1137 | @item :insert-button-args | |
6bf7aab6 DL |
1138 | A list of keyword arguments to pass to the insert buttons. |
1139 | ||
6f7f063d | 1140 | @vindex delete-button-args@r{ keyword} |
6bf7aab6 DL |
1141 | @item :delete-button-args |
1142 | A list of keyword arguments to pass to the delete buttons. | |
1143 | ||
6f7f063d | 1144 | @vindex append-button-args@r{ keyword} |
6bf7aab6 DL |
1145 | @item :append-button-args |
1146 | A list of keyword arguments to pass to the trailing insert button. | |
1147 | ||
6f7f063d | 1148 | @vindex buttons@r{ keyword} |
6bf7aab6 DL |
1149 | @item :buttons |
1150 | The widgets representing the insert and delete buttons. | |
1151 | ||
6f7f063d | 1152 | @vindex children@r{ keyword} |
6bf7aab6 DL |
1153 | @item :children |
1154 | The widgets representing the elements of the list. | |
1155 | ||
6f7f063d | 1156 | @vindex args@r{ keyword} |
6bf7aab6 | 1157 | @item :args |
9995b954 | 1158 | List whose @sc{car} is the type of the list elements. |
6bf7aab6 DL |
1159 | @end table |
1160 | ||
1161 | @node group, , editable-list, Basic Types | |
1162 | @comment node-name, next, previous, up | |
1163 | @subsection The @code{group} Widget | |
6f7f063d | 1164 | @findex group@r{ widget} |
6bf7aab6 | 1165 | |
6f7f063d | 1166 | This widget simply group other widgets together. |
6bf7aab6 DL |
1167 | |
1168 | Syntax: | |
1169 | ||
1170 | @example | |
87171118 | 1171 | @var{type} ::= (group [@var{keyword} @var{argument}]... @var{type}...) |
6bf7aab6 DL |
1172 | @end example |
1173 | ||
177c0ea7 | 1174 | The value is a list, with one member for each @var{type}. |
6bf7aab6 DL |
1175 | |
1176 | @node Sexp Types, Widget Properties, Basic Types, Top | |
1177 | @comment | |
1178 | @section Sexp Types | |
6f7f063d | 1179 | @cindex sexp types |
6bf7aab6 | 1180 | |
9995b954 | 1181 | A number of widgets for editing @dfn{s-expressions} (Lisp types), sexp |
6f7f063d EZ |
1182 | for short, are also available. These basically fall in several |
1183 | categories described in this section. | |
6bf7aab6 DL |
1184 | |
1185 | @menu | |
177c0ea7 JB |
1186 | * constants:: |
1187 | * generic:: | |
1188 | * atoms:: | |
1189 | * composite:: | |
6bf7aab6 DL |
1190 | @end menu |
1191 | ||
1192 | @node constants, generic, Sexp Types, Sexp Types | |
1193 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1194 | @subsection The Constant Widgets |
1195 | @cindex constant widgets | |
6bf7aab6 | 1196 | |
9995b954 | 1197 | The @code{const} widget can contain any Lisp expression, but the user is |
6f7f063d EZ |
1198 | prohibited from editing it, which is mainly useful as a component of one |
1199 | of the composite widgets. | |
6bf7aab6 | 1200 | |
6f7f063d | 1201 | The syntax for the @code{const} widget is: |
6bf7aab6 DL |
1202 | |
1203 | @example | |
87171118 | 1204 | @var{type} ::= (const [@var{keyword} @var{argument}]... [ @var{value} ]) |
6bf7aab6 DL |
1205 | @end example |
1206 | ||
1207 | The @var{value}, if present, is used to initialize the @code{:value} | |
1208 | property and can be any s-expression. | |
1209 | ||
1210 | @deffn Widget const | |
1211 | This will display any valid s-expression in an immutable part of the | |
177c0ea7 | 1212 | buffer. |
6bf7aab6 DL |
1213 | @end deffn |
1214 | ||
1215 | There are two variations of the @code{const} widget, namely | |
1216 | @code{variable-item} and @code{function-item}. These should contain a | |
1217 | symbol with a variable or function binding. The major difference from | |
1218 | the @code{const} widget is that they will allow the user to see the | |
1219 | variable or function documentation for the symbol. | |
1220 | ||
1221 | @deffn Widget variable-item | |
1222 | An immutable symbol that is bound as a variable. | |
1223 | @end deffn | |
1224 | ||
1225 | @deffn Widget function-item | |
1226 | An immutable symbol that is bound as a function. | |
1227 | @end deffn | |
1228 | ||
1229 | @node generic, atoms, constants, Sexp Types | |
1230 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1231 | @subsection Generic Sexp Widget |
1232 | @cindex generic sexp widget | |
6bf7aab6 | 1233 | |
9995b954 | 1234 | The @code{sexp} widget can contain any Lisp expression, and allows the |
6bf7aab6 DL |
1235 | user to edit it inline in the buffer. |
1236 | ||
6f7f063d | 1237 | The syntax for the @code{sexp} widget is: |
6bf7aab6 DL |
1238 | |
1239 | @example | |
87171118 | 1240 | @var{type} ::= (sexp [@var{keyword} @var{argument}]... [ @var{value} ]) |
6bf7aab6 DL |
1241 | @end example |
1242 | ||
1243 | @deffn Widget sexp | |
1244 | This will allow you to edit any valid s-expression in an editable buffer | |
177c0ea7 | 1245 | field. |
6bf7aab6 DL |
1246 | |
1247 | The @code{sexp} widget takes the same keyword arguments as the | |
6f7f063d | 1248 | @code{editable-field} widget. @xref{editable-field}. |
6bf7aab6 DL |
1249 | @end deffn |
1250 | ||
1251 | @node atoms, composite, generic, Sexp Types | |
1252 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1253 | @subsection Atomic Sexp Widgets |
1254 | @cindex atomic sexp widget | |
6bf7aab6 | 1255 | |
6f7f063d EZ |
1256 | The atoms are s-expressions that do not consist of other s-expressions. |
1257 | For example, a string, a file name, or a symbol are atoms, while a list | |
1258 | is a composite type. You can edit the value of an atom with the | |
1259 | following widgets. | |
6bf7aab6 | 1260 | |
6f7f063d | 1261 | The syntax for all the atoms are: |
6bf7aab6 DL |
1262 | |
1263 | @example | |
87171118 | 1264 | @var{type} ::= (@var{construct} [@var{keyword} @var{argument}]... [ @var{value} ]) |
6bf7aab6 DL |
1265 | @end example |
1266 | ||
1267 | The @var{value}, if present, is used to initialize the @code{:value} | |
1268 | property and must be an expression of the same type as the widget. | |
6f7f063d | 1269 | That is, the string widget can only be initialized with a string. |
6bf7aab6 DL |
1270 | |
1271 | All the atom widgets take the same keyword arguments as the | |
6f7f063d | 1272 | @code{editable-field} widget. @xref{editable-field}. |
6bf7aab6 DL |
1273 | |
1274 | @deffn Widget string | |
1275 | Allows you to edit a string in an editable field. | |
1276 | @end deffn | |
1277 | ||
1278 | @deffn Widget regexp | |
1279 | Allows you to edit a regular expression in an editable field. | |
1280 | @end deffn | |
1281 | ||
1282 | @deffn Widget character | |
1283 | Allows you to enter a character in an editable field. | |
1284 | @end deffn | |
1285 | ||
1286 | @deffn Widget file | |
2f04a835 | 1287 | Allows you to edit a file name in an editable field. |
6bf7aab6 DL |
1288 | |
1289 | Keywords: | |
1290 | @table @code | |
6f7f063d | 1291 | @vindex must-match@r{ keyword} |
6bf7aab6 | 1292 | @item :must-match |
9995b954 JH |
1293 | If this is set to non-@code{nil}, only existing file names will be |
1294 | allowed in the minibuffer. | |
6bf7aab6 DL |
1295 | @end table |
1296 | @end deffn | |
1297 | ||
1298 | @deffn Widget directory | |
1299 | Allows you to edit a directory name in an editable field. | |
1300 | Similar to the @code{file} widget. | |
1301 | @end deffn | |
1302 | ||
1303 | @deffn Widget symbol | |
9995b954 | 1304 | Allows you to edit a Lisp symbol in an editable field. |
6bf7aab6 DL |
1305 | @end deffn |
1306 | ||
1307 | @deffn Widget function | |
1308 | Allows you to edit a lambda expression, or a function name with completion. | |
1309 | @end deffn | |
1310 | ||
1311 | @deffn Widget variable | |
1312 | Allows you to edit a variable name, with completion. | |
1313 | @end deffn | |
1314 | ||
1315 | @deffn Widget integer | |
1316 | Allows you to edit an integer in an editable field. | |
1317 | @end deffn | |
1318 | ||
1319 | @deffn Widget number | |
1320 | Allows you to edit a number in an editable field. | |
1321 | @end deffn | |
1322 | ||
1323 | @deffn Widget boolean | |
9995b954 JH |
1324 | Allows you to edit a boolean. In Lisp this means a variable which is |
1325 | either @code{nil} meaning false, or non-@code{nil} meaning true. | |
6bf7aab6 DL |
1326 | @end deffn |
1327 | ||
1328 | ||
1329 | @node composite, , atoms, Sexp Types | |
1330 | @comment node-name, next, previous, up | |
6f7f063d EZ |
1331 | @subsection Composite Sexp Widgets |
1332 | @cindex composite sexp widgets | |
6bf7aab6 | 1333 | |
87171118 | 1334 | The syntax for the composite widget construct is: |
6bf7aab6 DL |
1335 | |
1336 | @example | |
87171118 | 1337 | @var{type} ::= (@var{construct} [@var{keyword} @var{argument}]... @var{component}...) |
6bf7aab6 DL |
1338 | @end example |
1339 | ||
6f7f063d EZ |
1340 | @noindent |
1341 | where each @var{component} must be a widget type. Each component widget | |
1342 | will be displayed in the buffer, and will be editable by the user. | |
6bf7aab6 DL |
1343 | |
1344 | @deffn Widget cons | |
87171118 RS |
1345 | The value of a @code{cons} widget must be a cons-cell whose @sc{car} |
1346 | and @sc{cdr} have two specified types. It uses this syntax: | |
1347 | ||
1348 | @example | |
1349 | @var{type} ::= (cons [@var{keyword} @var{argument}]... @var{car-type} @var{cdr-type}) | |
1350 | @end example | |
1351 | @end deffn | |
1352 | ||
1353 | @deffn Widget choice | |
7da31552 RS |
1354 | The value matched by a @code{choice} widget must have one of a fixed |
1355 | set of types. The widget's syntax is as follows: | |
87171118 RS |
1356 | |
1357 | @example | |
1358 | @var{type} ::= (choice [@var{keyword} @var{argument}]... @var{type} ... ) | |
1359 | @end example | |
1360 | ||
1361 | The value of a @code{choice} widget can be anything that matches any of the | |
1362 | @var{types}. | |
6bf7aab6 DL |
1363 | @end deffn |
1364 | ||
1365 | @deffn Widget list | |
87171118 RS |
1366 | The value of a @code{list} widget must be a list whose element types |
1367 | match the specified component types: | |
1368 | ||
1369 | @example | |
1370 | @var{type} ::= (list [@var{keyword} @var{argument}]... @var{component-type}...) | |
1371 | @end example | |
1372 | ||
1373 | Thus, @code{(list string number)} matches lists of two elements, | |
1374 | the first being a string and the second being a number. | |
6bf7aab6 DL |
1375 | @end deffn |
1376 | ||
1377 | @deffn Widget vector | |
87171118 RS |
1378 | The @code{vector} widget is like the @code{list} widget but matches |
1379 | vectors instead of lists. Thus, @code{(vector string number)} matches | |
1380 | vectors of two elements, the first being a string and the second being | |
1381 | a number. | |
6bf7aab6 DL |
1382 | @end deffn |
1383 | ||
1384 | The above suffice for specifying fixed size lists and vectors. To get | |
1385 | variable length lists and vectors, you can use a @code{choice}, | |
db71197e | 1386 | @code{set}, or @code{repeat} widget together with the @code{:inline} |
7da31552 RS |
1387 | keyword. If any component of a composite widget has the |
1388 | @code{:inline} keyword set, its value must be a list which will then | |
1389 | be spliced into the composite. For example, to specify a list whose | |
1390 | first element must be a file name, and whose remaining elements should | |
1391 | either be the symbol @code{t} or two strings (file names), you can use | |
1392 | the following widget specification: | |
6bf7aab6 DL |
1393 | |
1394 | @example | |
1395 | (list file | |
1396 | (choice (const t) | |
1397 | (list :inline t | |
1398 | :value ("foo" "bar") | |
1399 | string string))) | |
1400 | @end example | |
1401 | ||
177c0ea7 | 1402 | The value of a widget of this type will either have the form |
87171118 | 1403 | @code{(file t)} or @code{(file @var{string} @var{string})}. |
6bf7aab6 | 1404 | |
87171118 RS |
1405 | This concept of @code{:inline} may be hard to understand. It was |
1406 | certainly hard to implement, so instead of confusing you more by | |
1407 | trying to explain it here, I'll just suggest you meditate over it for | |
1408 | a while. | |
6bf7aab6 DL |
1409 | |
1410 | @deffn Widget set | |
87171118 RS |
1411 | Specifies a type whose values are the lists whose elements all belong |
1412 | to a given set. The order of elements of the list is not significant. | |
1413 | Here's the syntax: | |
1414 | ||
1415 | @example | |
1416 | @var{type} ::= (set [@var{keyword} @var{argument}]... @var{permitted-element} ... ) | |
1417 | @end example | |
1418 | ||
1419 | Use @code{const} to specify each permitted element, like this: | |
1420 | @code{(set (const a) (const b))}. | |
6bf7aab6 DL |
1421 | @end deffn |
1422 | ||
1423 | @deffn Widget repeat | |
87171118 RS |
1424 | Specifies a list of any number of elements that fit a certain type. |
1425 | ||
1426 | @example | |
1427 | @var{type} ::= (repeat [@var{keyword} @var{argument}]... @var{type}) | |
1428 | @end example | |
6bf7aab6 DL |
1429 | @end deffn |
1430 | ||
1431 | @node Widget Properties, Defining New Widgets, Sexp Types, Top | |
1432 | @comment node-name, next, previous, up | |
1433 | @section Properties | |
6f7f063d EZ |
1434 | @cindex properties of widgets |
1435 | @cindex widget properties | |
6bf7aab6 DL |
1436 | |
1437 | You can examine or set the value of a widget by using the widget object | |
1438 | that was returned by @code{widget-create}. | |
1439 | ||
1440 | @defun widget-value widget | |
1441 | Return the current value contained in @var{widget}. | |
1442 | It is an error to call this function on an uninitialized widget. | |
1443 | @end defun | |
1444 | ||
1445 | @defun widget-value-set widget value | |
1446 | Set the value contained in @var{widget} to @var{value}. | |
1447 | It is an error to call this function with an invalid @var{value}. | |
1448 | @end defun | |
1449 | ||
1450 | @strong{Important:} You @emph{must} call @code{widget-setup} after | |
1451 | modifying the value of a widget before the user is allowed to edit the | |
1452 | widget again. It is enough to call @code{widget-setup} once if you | |
1453 | modify multiple widgets. This is currently only necessary if the widget | |
1454 | contains an editing field, but may be necessary for other widgets in the | |
177c0ea7 | 1455 | future. |
6bf7aab6 DL |
1456 | |
1457 | If your application needs to associate some information with the widget | |
1458 | objects, for example a reference to the item being edited, it can be | |
1459 | done with @code{widget-put} and @code{widget-get}. The property names | |
1460 | must begin with a @samp{:}. | |
1461 | ||
1462 | @defun widget-put widget property value | |
1463 | In @var{widget} set @var{property} to @var{value}. | |
1464 | @var{property} should be a symbol, while @var{value} can be anything. | |
1465 | @end defun | |
1466 | ||
1467 | @defun widget-get widget property | |
1468 | In @var{widget} return the value for @var{property}. | |
1469 | @var{property} should be a symbol, the value is what was last set by | |
1470 | @code{widget-put} for @var{property}. | |
1471 | @end defun | |
1472 | ||
1473 | @defun widget-member widget property | |
9995b954 JH |
1474 | Non-@code{nil} if @var{widget} has a value (even @code{nil}) for |
1475 | property @var{property}. | |
6bf7aab6 DL |
1476 | @end defun |
1477 | ||
1478 | Occasionally it can be useful to know which kind of widget you have, | |
177c0ea7 | 1479 | i.e.@: the name of the widget type you gave when the widget was created. |
6bf7aab6 DL |
1480 | |
1481 | @defun widget-type widget | |
1482 | Return the name of @var{widget}, a symbol. | |
1483 | @end defun | |
1484 | ||
6f7f063d EZ |
1485 | @cindex active widget |
1486 | @cindex inactive widget | |
1487 | @cindex activate a widget | |
1488 | @cindex deactivate a widget | |
6bf7aab6 DL |
1489 | Widgets can be in two states: active, which means they are modifiable by |
1490 | the user, or inactive, which means they cannot be modified by the user. | |
1491 | You can query or set the state with the following code: | |
1492 | ||
1493 | @lisp | |
1494 | ;; Examine if @var{widget} is active or not. | |
1495 | (if (widget-apply @var{widget} :active) | |
1496 | (message "Widget is active.") | |
1497 | (message "Widget is inactive.") | |
1498 | ||
1499 | ;; Make @var{widget} inactive. | |
1500 | (widget-apply @var{widget} :deactivate) | |
1501 | ||
1502 | ;; Make @var{widget} active. | |
1503 | (widget-apply @var{widget} :activate) | |
1504 | @end lisp | |
1505 | ||
54438eb5 DL |
1506 | A widget is inactive if it, or any of its ancestors (found by |
1507 | following the @code{:parent} link), have been deactivated. To make sure | |
1508 | a widget is really active, you must therefore activate both it and | |
6bf7aab6 DL |
1509 | all its ancestors. |
1510 | ||
1511 | @lisp | |
177c0ea7 | 1512 | (while widget |
6bf7aab6 DL |
1513 | (widget-apply widget :activate) |
1514 | (setq widget (widget-get widget :parent))) | |
1515 | @end lisp | |
1516 | ||
1517 | You can check if a widget has been made inactive by examining the value | |
9995b954 | 1518 | of the @code{:inactive} keyword. If this is non-@code{nil}, the widget itself |
54438eb5 DL |
1519 | has been deactivated. This is different from using the @code{:active} |
1520 | keyword, in that the latter tells you if the widget @strong{or} any of | |
1521 | its ancestors have been deactivated. Do not attempt to set the | |
6bf7aab6 | 1522 | @code{:inactive} keyword directly. Use the @code{:activate} |
54438eb5 | 1523 | @code{:deactivate} keywords instead. |
6bf7aab6 DL |
1524 | |
1525 | ||
1526 | @node Defining New Widgets, Widget Browser, Widget Properties, Top | |
1527 | @comment node-name, next, previous, up | |
1528 | @section Defining New Widgets | |
6f7f063d EZ |
1529 | @cindex new widgets |
1530 | @cindex defining new widgets | |
6bf7aab6 | 1531 | |
75ba82a9 | 1532 | You can define specialized widgets with @code{define-widget}. It allows |
6bf7aab6 | 1533 | you to create a shorthand for more complex widgets, including specifying |
54438eb5 | 1534 | component widgets and new default values for the keyword |
177c0ea7 | 1535 | arguments. |
6bf7aab6 | 1536 | |
75ba82a9 | 1537 | @defun define-widget name class doc &rest args |
6bf7aab6 DL |
1538 | Define a new widget type named @var{name} from @code{class}. |
1539 | ||
1540 | @var{name} and class should both be symbols, @code{class} should be one | |
177c0ea7 | 1541 | of the existing widget types. |
6bf7aab6 | 1542 | |
9995b954 | 1543 | The third argument @var{doc} is a documentation string for the widget. |
6bf7aab6 DL |
1544 | |
1545 | After the new widget has been defined, the following two calls will | |
1546 | create identical widgets: | |
1547 | ||
1548 | @itemize @bullet | |
1549 | @item | |
1550 | @lisp | |
1551 | (widget-create @var{name}) | |
1552 | @end lisp | |
1553 | ||
1554 | @item | |
1555 | @lisp | |
1556 | (apply widget-create @var{class} @var{args}) | |
1557 | @end lisp | |
1558 | @end itemize | |
1559 | ||
1560 | @end defun | |
1561 | ||
75ba82a9 | 1562 | Using @code{define-widget} just stores the definition of the widget type |
54438eb5 | 1563 | in the @code{widget-type} property of @var{name}, which is what |
6bf7aab6 DL |
1564 | @code{widget-create} uses. |
1565 | ||
6f7f063d | 1566 | If you only want to specify defaults for keywords with no complex |
6bf7aab6 DL |
1567 | conversions, you can use @code{identity} as your conversion function. |
1568 | ||
1569 | The following additional keyword arguments are useful when defining new | |
177c0ea7 | 1570 | widgets: |
6bf7aab6 | 1571 | @table @code |
6f7f063d | 1572 | @vindex convert-widget@r{ keyword} |
6bf7aab6 DL |
1573 | @item :convert-widget |
1574 | Function to convert a widget type before creating a widget of that | |
1575 | type. It takes a widget type as an argument, and returns the converted | |
1576 | widget type. When a widget is created, this function is called for the | |
177c0ea7 | 1577 | widget type and all the widget's parent types, most derived first. |
6bf7aab6 DL |
1578 | |
1579 | The following predefined functions can be used here: | |
1580 | ||
1581 | @defun widget-types-convert-widget widget | |
1582 | Convert @code{:args} as widget types in @var{widget}. | |
1583 | @end defun | |
1584 | ||
1585 | @defun widget-value-convert-widget widget | |
1586 | Initialize @code{:value} from @code{:args} in @var{widget}. | |
1587 | @end defun | |
1588 | ||
4c2f559e PA |
1589 | @vindex copy@r{ keyword} |
1590 | @item :copy | |
1591 | Function to deep copy a widget type. It takes a shallow copy of the | |
1592 | widget type as an argument (made by @code{copy-sequence}), and returns a | |
1593 | deep copy. The purpose of this is to avoid having different instances | |
1594 | of combined widgets share nested attributes. | |
1595 | ||
1596 | The following predefined functions can be used here: | |
1597 | ||
1598 | @defun widget-types-copy widget | |
1599 | Copy @code{:args} as widget types in @var{widget}. | |
1600 | @end defun | |
1601 | ||
6f7f063d | 1602 | @vindex value-to-internal@r{ keyword} |
6bf7aab6 DL |
1603 | @item :value-to-internal |
1604 | Function to convert the value to the internal format. The function | |
1605 | takes two arguments, a widget and an external value, and returns the | |
1606 | internal value. The function is called on the present @code{:value} | |
1607 | when the widget is created, and on any value set later with | |
1608 | @code{widget-value-set}. | |
1609 | ||
6f7f063d | 1610 | @vindex value-to-external@r{ keyword} |
6bf7aab6 DL |
1611 | @item :value-to-external |
1612 | Function to convert the value to the external format. The function | |
1613 | takes two arguments, a widget and an internal value, and returns the | |
6f7f063d | 1614 | external value. The function is called on the present @code{:value} |
6bf7aab6 DL |
1615 | when the widget is created, and on any value set later with |
1616 | @code{widget-value-set}. | |
1617 | ||
6f7f063d | 1618 | @vindex create@r{ keyword} |
6bf7aab6 DL |
1619 | @item :create |
1620 | Function to create a widget from scratch. The function takes one | |
54438eb5 DL |
1621 | argument, a widget type, and creates a widget of that type, inserts it |
1622 | in the buffer, and returns a widget object. | |
6bf7aab6 | 1623 | |
6f7f063d | 1624 | @vindex delete@r{ keyword} |
6bf7aab6 DL |
1625 | @item :delete |
1626 | Function to delete a widget. The function takes one argument, a widget, | |
1627 | and should remove all traces of the widget from the buffer. | |
1628 | ||
1ded3d46 PA |
1629 | The default value is: |
1630 | ||
1631 | @defun widget-default-delete widget | |
1632 | Remove @var{widget} from the buffer. | |
1633 | Delete all @code{:children} and @code{:buttons} in @var{widget}. | |
1634 | @end defun | |
1635 | ||
1636 | In most cases you should not change this value, but instead use | |
1637 | @code{:value-delete} to make any additional cleanup. | |
1638 | ||
6f7f063d | 1639 | @vindex value-create@r{ keyword} |
6bf7aab6 DL |
1640 | @item :value-create |
1641 | Function to expand the @samp{%v} escape in the format string. It will | |
54438eb5 DL |
1642 | be called with the widget as its argument and should insert a |
1643 | representation of the widget's value in the buffer. | |
6bf7aab6 | 1644 | |
1ded3d46 PA |
1645 | Nested widgets should be listed in @code{:children} or @code{:buttons} |
1646 | to make sure they are automatically deleted. | |
1647 | ||
6f7f063d | 1648 | @vindex value-delete@r{ keyword} |
6bf7aab6 | 1649 | @item :value-delete |
54438eb5 | 1650 | Should remove the representation of the widget's value from the buffer. |
6bf7aab6 DL |
1651 | It will be called with the widget as its argument. It doesn't have to |
1652 | remove the text, but it should release markers and delete nested widgets | |
1ded3d46 | 1653 | if these are not listed in @code{:children} or @code{:buttons}. |
6bf7aab6 | 1654 | |
6f7f063d | 1655 | @vindex value-get@r{ keyword} |
177c0ea7 | 1656 | @item :value-get |
6bf7aab6 | 1657 | Function to extract the value of a widget, as it is displayed in the |
177c0ea7 | 1658 | buffer. |
6bf7aab6 DL |
1659 | |
1660 | The following predefined function can be used here: | |
1661 | ||
1662 | @defun widget-value-value-get widget | |
1663 | Return the @code{:value} property of @var{widget}. | |
1664 | @end defun | |
1665 | ||
6f7f063d | 1666 | @vindex format-handler@r{ keyword} |
6bf7aab6 DL |
1667 | @item :format-handler |
1668 | Function to handle unknown @samp{%} escapes in the format string. It | |
6f7f063d EZ |
1669 | will be called with the widget and the character that follows the |
1670 | @samp{%} as arguments. You can set this to allow your widget to handle | |
1671 | non-standard escapes. | |
6bf7aab6 | 1672 | |
6f7f063d | 1673 | @findex widget-default-format-handler |
6bf7aab6 DL |
1674 | You should end up calling @code{widget-default-format-handler} to handle |
1675 | unknown escape sequences, which will handle the @samp{%h} and any future | |
1676 | escape sequences, as well as give an error for unknown escapes. | |
1677 | ||
6f7f063d | 1678 | @vindex action@r{ keyword} |
6bf7aab6 DL |
1679 | @item :action |
1680 | Function to handle user initiated events. By default, @code{:notify} | |
177c0ea7 | 1681 | the parent. |
6bf7aab6 DL |
1682 | |
1683 | The following predefined function can be used here: | |
1684 | ||
1685 | @defun widget-parent-action widget &optional event | |
1686 | Tell @code{:parent} of @var{widget} to handle the @code{:action}. | |
1687 | Optional @var{event} is the event that triggered the action. | |
1688 | @end defun | |
1689 | ||
6f7f063d | 1690 | @vindex prompt-value@r{ keyword} |
6bf7aab6 DL |
1691 | @item :prompt-value |
1692 | Function to prompt for a value in the minibuffer. The function should | |
1693 | take four arguments, @var{widget}, @var{prompt}, @var{value}, and | |
1694 | @var{unbound} and should return a value for widget entered by the user. | |
1695 | @var{prompt} is the prompt to use. @var{value} is the default value to | |
9995b954 | 1696 | use, unless @var{unbound} is non-@code{nil}, in which case there is no default |
6bf7aab6 DL |
1697 | value. The function should read the value using the method most natural |
1698 | for this widget, and does not have to check that it matches. | |
1699 | @end table | |
1700 | ||
1701 | If you want to define a new widget from scratch, use the @code{default} | |
1702 | widget as its base. | |
1703 | ||
177c0ea7 JB |
1704 | @deffn Widget default |
1705 | Widget used as a base for other widgets. | |
6bf7aab6 DL |
1706 | |
1707 | It provides most of the functionality that is referred to as ``by | |
177c0ea7 | 1708 | default'' in this text. |
6bf7aab6 DL |
1709 | @end deffn |
1710 | ||
1711 | @node Widget Browser, Widget Minor Mode, Defining New Widgets, Top | |
1712 | @comment node-name, next, previous, up | |
1713 | @section Widget Browser | |
6f7f063d | 1714 | @cindex widget browser |
6bf7aab6 DL |
1715 | |
1716 | There is a separate package to browse widgets. This is intended to help | |
1717 | programmers who want to examine the content of a widget. The browser | |
1718 | shows the value of each keyword, but uses links for certain keywords | |
6f7f063d | 1719 | such as @samp{:parent}, which avoids printing cyclic structures. |
6bf7aab6 | 1720 | |
49c24f48 RS |
1721 | @deffn Command widget-browse @var{widget} |
1722 | Create a widget browser for @var{widget}. | |
1723 | When called interactively, prompt for @var{widget}. | |
6bf7aab6 DL |
1724 | @end deffn |
1725 | ||
49c24f48 RS |
1726 | @deffn Command widget-browse-other-window @var{widget} |
1727 | Create a widget browser for @var{widget} and show it in another window. | |
1728 | When called interactively, prompt for @var{widget}. | |
6bf7aab6 DL |
1729 | @end deffn |
1730 | ||
49c24f48 RS |
1731 | @deffn Command widget-browse-at @var{pos} |
1732 | Create a widget browser for the widget at @var{pos}. | |
6bf7aab6 DL |
1733 | When called interactively, use the position of point. |
1734 | @end deffn | |
1735 | ||
1736 | @node Widget Minor Mode, Utilities, Widget Browser, Top | |
1737 | @comment node-name, next, previous, up | |
1738 | @section Widget Minor Mode | |
6f7f063d | 1739 | @cindex widget minor mode |
6bf7aab6 DL |
1740 | |
1741 | There is a minor mode for manipulating widgets in major modes that | |
6f7f063d | 1742 | don't provide any support for widgets themselves. This is mostly |
177c0ea7 | 1743 | intended to be useful for programmers doing experiments. |
6bf7aab6 DL |
1744 | |
1745 | @deffn Command widget-minor-mode | |
1746 | Toggle minor mode for traversing widgets. | |
1747 | With arg, turn widget mode on if and only if arg is positive. | |
1748 | @end deffn | |
1749 | ||
1750 | @defvar widget-minor-mode-keymap | |
1751 | Keymap used in @code{widget-minor-mode}. | |
1752 | @end defvar | |
1753 | ||
1754 | @node Utilities, Widget Wishlist, Widget Minor Mode, Top | |
1755 | @comment node-name, next, previous, up | |
1756 | @section Utilities. | |
6f7f063d | 1757 | @cindex utility functions for widgets |
6bf7aab6 DL |
1758 | |
1759 | @defun widget-prompt-value widget prompt [ value unbound ] | |
1760 | Prompt for a value matching @var{widget}, using @var{prompt}. | |
1761 | The current value is assumed to be @var{value}, unless @var{unbound} is | |
9995b954 | 1762 | non-@code{nil}.@refill |
6bf7aab6 DL |
1763 | @end defun |
1764 | ||
1765 | @defun widget-get-sibling widget | |
6f7f063d | 1766 | Get the item which @var{widget} is assumed to toggle. |
6bf7aab6 DL |
1767 | This is only meaningful for radio buttons or checkboxes in a list. |
1768 | @end defun | |
1769 | ||
6f7f063d | 1770 | @node Widget Wishlist, Index, Utilities, Top |
6bf7aab6 DL |
1771 | @comment node-name, next, previous, up |
1772 | @section Wishlist | |
6f7f063d | 1773 | @cindex todo |
6bf7aab6 DL |
1774 | |
1775 | @itemize @bullet | |
177c0ea7 | 1776 | @item |
6bf7aab6 DL |
1777 | It should be possible to add or remove items from a list with @kbd{C-k} |
1778 | and @kbd{C-o} (suggested by @sc{rms}). | |
1779 | ||
177c0ea7 | 1780 | @item |
976e00f1 DL |
1781 | The @samp{[INS]} and @samp{[DEL]} buttons should be replaced by a single |
1782 | dash (@samp{-}). The dash should be a button that, when invoked, asks | |
1783 | whether you want to add or delete an item (@sc{rms} wanted to git rid of | |
1784 | the ugly buttons, the dash is my idea). | |
1785 | ||
6bf7aab6 DL |
1786 | @item |
1787 | The @code{menu-choice} tag should be prettier, something like the abbreviated | |
1788 | menus in Open Look. | |
1789 | ||
1790 | @item | |
1791 | Finish @code{:tab-order}. | |
1792 | ||
1793 | @item | |
1794 | Make indentation work with glyphs and proportional fonts. | |
1795 | ||
1796 | @item | |
1797 | Add commands to show overview of object and class hierarchies to the | |
177c0ea7 | 1798 | browser. |
6bf7aab6 | 1799 | |
177c0ea7 | 1800 | @item |
6bf7aab6 DL |
1801 | Find a way to disable mouse highlight for inactive widgets. |
1802 | ||
1803 | @item | |
1804 | Find a way to make glyphs look inactive. | |
1805 | ||
976e00f1 DL |
1806 | @item |
1807 | Add @code{property-list} widget. | |
1808 | ||
1809 | @item | |
1810 | Add @code{association-list} widget. | |
1811 | ||
6bf7aab6 DL |
1812 | @item |
1813 | Add @code{key-binding} widget. | |
1814 | ||
1815 | @item | |
1816 | Add @code{widget} widget for editing widget specifications. | |
1817 | ||
1818 | @item | |
1819 | Find clean way to implement variable length list. | |
1820 | See @code{TeX-printer-list} for an explanation. | |
1821 | ||
177c0ea7 | 1822 | @item |
6bf7aab6 DL |
1823 | @kbd{C-h} in @code{widget-prompt-value} should give type specific help. |
1824 | ||
177c0ea7 | 1825 | @item |
6f7f063d | 1826 | Add a @code{mailto} widget. |
6bf7aab6 DL |
1827 | @end itemize |
1828 | ||
6f7f063d EZ |
1829 | @node Index, , Widget Wishlist, Top |
1830 | @comment node-name, next, previous, up | |
1831 | @unnumbered Index | |
1832 | ||
1833 | This is an alphabetical listing of all concepts, functions, commands, | |
1834 | variables, and widgets described in this manual. | |
1835 | @printindex cp | |
1836 | ||
56f7c94a | 1837 | @setchapternewpage odd |
6bf7aab6 DL |
1838 | @contents |
1839 | @bye | |
ab5796a9 MB |
1840 | |
1841 | @ignore | |
1842 | arch-tag: 2b427731-4c61-4e72-85de-5ccec9c623f0 | |
1843 | @end ignore |