5 @settitle The Customization Library
12 @node Top, Introduction, (dir), (dir)
13 @comment node-name, next, previous, up
14 @top The Customization Library
21 * The Customization Buffer::
28 @node Introduction, User Commands, Top, Top
29 @comment node-name, next, previous, up
32 This library allows customization of @dfn{user options}. Currently two
33 types of user options are supported, namely @dfn{variables} and
34 @dfn{faces}. Each user option can have four different values
38 The value specified by the programmer.
40 The value saved by the user as the default for this variable. This
41 overwrites the factory setting when starting a new emacs.
43 The value used by Emacs. This will not be remembered next time you
46 The value entered by the user in a customization buffer, but not yet
50 Variables also have a @dfn{type}, which specifies what kind of values
51 the variable can hold, and how the value is presented in a customization
52 buffer. By default a variable can hold any valid expression, but the
53 programmer can specify a more limited type when declaring the variable.
55 The user options are organized in a number of @dfn{groups}. Each group
56 can contain a number user options, as well as other groups. The groups
57 allows the user to concentrate on a specific part of emacs.
59 @node User Commands, The Customization Buffer, Introduction, Top
60 @comment node-name, next, previous, up
61 @section User Commands
63 The following commands will create a customization buffer:
67 Create a customization buffer containing a specific group, by default
68 the @code{emacs} group.
70 @item customize-variable
71 Create a customization buffer containing a single variable.
74 Create a customization buffer containing a single face.
76 @item customize-apropos
77 Create a customization buffer containing all variables, faces, and
78 groups that match a user specified regular expression.
81 @node The Customization Buffer, Declarations, User Commands, Top
82 @comment node-name, next, previous, up
83 @section The Customization Buffer.
85 The customization buffer allows the user to make temporary or permanent
86 changes to how specific aspects of emacs works, by setting and editing
89 The customization buffer contains three types of text:
92 @item informative text
93 where the normal editing commands are disabled.
96 where you can edit with the usual emacs commands. Editable fields are
97 usually displayed with a grey background if your terminal supports
98 colors, or an italic font otherwise.
101 which can be activated by either pressing the @kbd{@key{ret}} while
102 point is located on the text, or pushing @kbd{mouse-2} while the mouse
103 pointer is above the tex. Buttons are usually displayed in a bold
107 You can move to the next the next editable field or button by pressing
108 @kbd{@key{tab}} or the previous with @kbd{M-@key{tab}}. Some buttons
109 have a small helpful message about their purpose, which will be
110 displayed when you move to it with the @key{tab} key.
112 The buffer is divided into three part, an introductory text, a list of
113 customization options, and a line of customization buttons. Each part
114 will be described in the following.
117 * The Introductory Text::
118 * The Customization Options::
119 * The Variable Options::
121 * The Group Options::
123 * The Customization Buttons::
126 @node The Introductory Text, The Customization Options, The Customization Buffer, The Customization Buffer
127 @comment node-name, next, previous, up
128 @subsection The Introductory Text
130 The start of the buffer contains a short explanation of what it is, and
131 how to get help. It will typically look like this:
134 This is a customization buffer.
135 Push RET or click mouse-2 on the word _help_ for more information.
138 Rather boring. It is mostly just informative text, but the word
139 @samp{help} is a button that will bring up this document when
142 @node The Customization Options, The Variable Options, The Introductory Text, The Customization Buffer
143 @comment node-name, next, previous, up
144 @subsection The Customization Options
146 Each customization option looks similar to the following text:
149 *** custom-background-mode: default
150 State: this item is unchanged from its factory setting.
151 [ ] [?] The brightness of the background.
154 The option contains the parts described below.
158 The Level Button. The customization options in the buffer are organized
159 in a hierarchy, which is indicated by the number of stars in the level
160 button. The top level options will be shown as @samp{*}. When they are
161 expanded, the suboptions will be shown as @samp{**}. The example option
162 is thus a subsuboption.
164 Activating the level buttons will toggle between hiding and exposing the
165 content of that option. The content can either be the value of the
166 option, as in this example, or a list of suboptions.
168 @item custom-background-mode
169 This is the tag of the the option. The tag is a name of a variable, a
170 face, or customization group. Activating the tag has an effect that
171 depends on the exact type of the option. In this particular case,
172 activating the tag will bring up a menu that will allow you to choose
173 from the three possible values of the `custom-background-mode'
177 After the tag, the options value is shown. Depending on its type, you
178 may be able to edit the value directly. If an option should contain a
179 file name, it is displayed in an editable field, i.e. you can edit it
180 using the standard emacs editing commands.
182 @item State: this item is unchanged from its factory setting.
183 The state line. This line will explain the state of the option,
184 e.g. whether it is currently hidden, or whether it has been modified or
185 not. Activating the button will allow you to change the state, e.g. set
186 or reset the changes you have made. This is explained in detail in the
190 The magic button. This is an abbreviated version of the state line.
193 The documentation button. If the documentation is more than one line,
194 this button will be present. Activating the button will toggle whether
195 the complete documentation is shown, or only the first line.
197 @item The brightness of the background.
198 This is a documentation string explaining the purpose of this particular
199 customization option.
203 @node The Variable Options, The Face Options, The Customization Options, The Customization Buffer
204 @comment node-name, next, previous, up
205 @subsection The Variable Options
207 The most common customization options are emacs lisp variables. The
208 actual editing of these variables depend on what type values the
209 variable is expected to contain. For example, a lisp variable whose
210 value should be a string will typically be represented with an editable
211 text field in the buffer, where you can change the string directly. If
212 the value is a list, each item in the list will be presented in the
213 buffer buffer on a separate line, with buttons to insert new items in
214 the list, or delete existing items from the list. You may want to see
215 @ref{User Interface,,, widget, The Widget Library}, where some examples
216 of editing are discussed.
218 You can either choose to edit the value directly, or edit the lisp
219 value for that variable. The lisp value is a lisp expression that
220 will be evaluated when you start emacs. The result of the evaluation
221 will be used as the initial value for that variable. Editing the
222 lisp value is for experts only, but if the current value of the
223 variable is of a wrong type (i.e. a symbol where a string is expected),
224 the `edit lisp' mode will always be selected.
226 You can see what mode is currently selected by looking at the state
227 button. If it uses parenthesises (like @samp{( )}) it is in edit lisp
228 mode, with square brackets (like @samp{[ ]}) it is normal edit mode.
229 You can switch mode by activating the state button, and select either
230 @samp{Edit} or @samp{Edit lisp} from the menu.
232 You can change the state of the variable with the other menu items:
236 When you have made your modifications in the buffer, you need to
237 activate this item to make the modifications take effect. The
238 modifications will be forgotten next time you run emacs.
241 Unless you activate this item instead! This will mark the modification
242 as permanent, i.e. the changes will be remembered in the next emacs
246 If you have made some modifications and not yet applied them, you can
247 undo the modification by activating this item.
250 Activating this item will reset the value of the variable to the last
251 value you marked as permanent with `Save'.
253 @item Reset to Factory Settings
254 Activating this item will undo all modifications you have made, and
255 reset the value to the initial value specified by the program itself.
258 By default, the value of large or complicated variables are hidden. You
259 can show the value by clicking on the level button.
261 @node The Face Options, The Group Options, The Variable Options, The Customization Buffer
262 @comment node-name, next, previous, up
263 @subsection The Face Options
265 A face is an object that controls the appearance of some buffer text.
266 The face has a number of possible attributes, such as boldness,
267 foreground color, and more. For each attribute you can specify whether
268 this attribute is controlled by the face, and if so, what the value is.
269 For example, if the attribute bold is not controlled by a face, using
270 that face on some buffer text will not affect its boldness. If the bold
271 attribute is controlled by the face, it can be turned either on or of.
273 It is possible to specify that a face should have different attributes
274 on different device types. For example, a face may make text red on a
275 color device, and bold on a monochrome device.
277 The way this is presented in the customization buffer is to have a list
278 of display specifications, and for each display specification a list of
279 face attributes. For each face attribute, there is a checkbox
280 specifying whether this attribute has effect and what the value is.
284 *** custom-invalid-face: (sample)
285 [ ] Face used when the customize item is invalid.
286 [INS] [DEL] Display: [ ] Type: [ ] X [ ] TTY
287 [X] Class: [X] Color [ ] Grayscale [ ] Monochrome
288 [ ] Background: [ ] Light [ ] Dark
289 Attributes: [ ] Bold: off
292 [X] Foreground: yellow (sample)
293 [X] Background: red (sample)
295 [INS] [DEL] Display: all
296 Attributes: [X] Bold: on
299 [ ] Foreground: default (sample)
300 [ ] Background: default (sample)
305 This has two display specifications. The first will match all color
306 displays, independently on whether the device is X11 or a tty, and
307 whether background color is dark or light. For devices matching this
308 specification, @samp{custom-invalid-face} will force text to be
309 displayed in yellow on red, but leave all other attributes alone.
311 The second display will simply match everything. Since the list is
312 prioritised, this means that it will match all non-color displays. For
313 these, the face will not affect the foreground or background color, but
314 force the font to be both bold, italic, and underline.
316 You can add or delete display specifications by activating the
317 @samp{[INS]} and @samp{[DEL]} buttons, and modify them by clicking on
318 the check boxes. The first checkbox in each line in the display
319 specification is special. It specify whether this particular property
320 will even be relevant. By not checking the box in the first display, we
321 match all device types, also device types other than X11 and tty, for
322 example ms-windows, nextstep, and mac os.
324 After modifying the face, you can activate the state button to make the
325 changes take effect. The menu items in the state button menu is similar
326 to the state menu items for variables described in the previous section.
328 @node The Group Options, The State Button, The Face Options, The Customization Buffer
329 @comment node-name, next, previous, up
330 @subsection The Group Options
332 Since Emacs has approximately a zillion configuration options, they have
333 been organized in groups. Each group can contain other groups, thus
334 creating a customization hierarchy. The nesting of the customization
335 within the visible part of this hierarchy is indicated by the number of
336 stars in the level button.
338 Since there is really no customization needed for the group itself, the
339 menu items in the groups state button will affect all modified group
340 members recursively. Thus, if you activate the @samp{Set} menu item,
341 all variables and faces that have been modified and belong to that group
342 will be applied. For those members that themselves are groups, it will
343 work as if you had activated the @samp{Set} menu item on them as well.
345 @node The State Button, The Customization Buttons, The Group Options, The Customization Buffer
346 @comment node-name, next, previous, up
347 @subsection The State Line and The Magic Button
349 The state line has two purposes. The first is to hold the state menu,
350 as described in the previous sections. The second is to indicate the
351 state of each customization item.
353 For the magic button, this is done by the character inside the brackets.
354 The following states have been defined, the first that applies to the
355 current item will be used:
359 The option is currently hidden. For group options that means the
360 members are not shown, for variables and faces that the value is not
361 shown. You cannot perform any of the state change operations on a
362 hidden customization option.
365 The value if this option has been modified in the buffer, but not yet
369 The item has has been set by the user.
372 The current value of this option is different from the saved value.
375 The saved value of this option is different from the factory setting.
378 The factory setting of this option is not known. This occurs when you
379 try to customize variables or faces that have not been explicitly
380 declared as customizable.
383 The factory setting is still in effect.
387 For non-hidden group options, the state shown is the most severe state
388 of its members, where more severe means that it appears earlier in the
389 list above (except hidden members, which are ignored).
391 @node The Customization Buttons, , The State Button, The Customization Buffer
392 @comment node-name, next, previous, up
393 @subsection The Customization Buttons
395 The last part of the customization buffer looks like this:
398 [Set] [Save] [Reset] [Done]
401 Activating the @samp{[Set]}, @samp{[Save]}, or @samp{[Reset]}
402 button will affect all modified customization items that are visible in
403 the buffer. @samp{[Done]} will bury the buffer.
405 @node Declarations, Utilities, The Customization Buffer, Top
406 @comment node-name, next, previous, up
407 @section Declarations
411 * Declaring Variables::
413 * Usage for Package Authors::
416 All the customization declarations can be changes by keyword arguments.
417 Groups, variables, and faces all share these common keywords:
421 @var{value} should be a customization group.
422 Add @var{symbol} to that group.
424 @var{value} should be a widget type.
425 Add @var{value} to the extrenal links for this customization option.
426 Useful widget types include @code{custom-manual}, @code{info-link}, and
429 Add @var{value} to the files that should be loaded nefore displaying
430 this customization option. The value should be iether a string, which
431 should be a string which will be loaded with @code{load-library} unless
432 present in @code{load-history}, or a symbol which will be loaded with
435 @var{Value} should be a short string used for identifying the option in
436 customization menus and buffers. By default the tag will be
437 automatically created from the options name.
440 @node Declaring Groups, Declaring Variables, Declarations, Declarations
441 @comment node-name, next, previous, up
442 @subsection Declaring Groups
444 Use @code{defgroup} to declare new customization groups.
446 @defun defgroup symbol members doc [keyword value]...
447 Declare @var{symbol} as a customization group containing @var{members}.
448 @var{symbol} does not need to be quoted.
450 @var{doc} is the group documentation.
452 @var{members} should be an alist of the form ((@var{name}
453 @var{widget})...) where @var{name} is a symbol and @var{widget} is a
454 widget for editing that symbol. Useful widgets are
455 @code{custom-variable} for editing variables, @code{custom-face} for
456 editing faces, and @code{custom-group} for editing groups.@refill
458 Internally, custom uses the symbol property @code{custom-group} to keep
459 track of the group members, and @code{group-documentation} for the
460 documentation string.
462 The following additional @var{keyword}'s are defined:
466 @var{value} should be a string. If the string is a prefix for the name
467 of a member of the group, that prefix will be ignored when creating a
472 @node Declaring Variables, Declaring Faces, Declaring Groups, Declarations
473 @comment node-name, next, previous, up
474 @subsection Declaring Variables
476 Use @code{defcustom} to declare user editable variables.
478 @defun defcustom symbol value doc [keyword value]...
479 Declare @var{symbol} as a customizable variable that defaults to @var{value}.
480 Neither @var{symbol} nor @var{value} needs to be quoted.
481 If @var{symbol} is not already bound, initialize it to @var{value}.
483 @var{doc} is the variable documentation.
485 The following additional @var{keyword}'s are defined:
489 @var{value} should be a widget type.
491 @var{value} should be a list of possible members of the specified type.
492 For hooks, this is a list of function names.
495 @xref{Sexp Types,,,widget,The Widget Library}, for information about
496 widgets to use together with the @code{:type} keyword.
499 Internally, custom uses the symbol property @code{custom-type} to keep
500 track of the variables type, @code{factory-value} for the program
501 specified default value, @code{saved-value} for a value saved by the
502 user, and @code{variable-documentation} for the documentation string.
504 Use @code{custom-add-option} to specify that a specific function is
505 useful as an meber of a hook.
507 @defun custom-add-option symbol option
508 To the variable @var{symbol} add @var{option}.
510 If @var{symbol} is a hook variable, @var{option} should be a hook
511 member. For other types variables, the effect is undefined."
514 @node Declaring Faces, Usage for Package Authors, Declaring Variables, Declarations
515 @comment node-name, next, previous, up
516 @subsection Declaring Faces
518 Faces are declared with @code{defface}.
520 @defun defface face spec doc [keyword value]...
522 Declare @var{face} as a customizable face that defaults to @var{spec}.
523 @var{face} does not need to be quoted.
525 If @var{face} has been set with `custom-set-face', set the face attributes
526 as specified by that function, otherwise set the face attributes
527 according to @var{spec}.
529 @var{doc} is the face documentation.
531 @var{spec} should be an alist of the form @samp{((@var{display} @var{atts})...)}.
533 @var{atts} is a list of face attributes and their values. The possible
534 attributes are defined in the variable `custom-face-attributes'.
535 Alternatively, @var{atts} can be a face in which case the attributes of
538 The @var{atts} of the first entry in @var{spec} where the @var{display}
539 matches the frame should take effect in that frame. @var{display} can
540 either be the symbol `t', which will match all frames, or an alist of
541 the form @samp{((@var{req} @var{item}...)...)}@refill
543 For the @var{display} to match a FRAME, the @var{req} property of the
544 frame must match one of the @var{item}. The following @var{req} are
549 (the value of (window-system))@*
550 Should be one of @code{x} or @code{tty}.
553 (the frame's color support)@*
554 Should be one of @code{color}, @code{grayscale}, or @code{mono}.
557 (what color is used for the background text)@*
558 Should be one of @code{light} or @code{dark}.
561 Internally, custom uses the symbol property @code{factory-face} for the
562 program specified default face properties, @code{saved-face} for
563 properties saved by the user, and @code{face-doc-string} for the
564 documentation string.@refill
568 @node Usage for Package Authors, , Declaring Faces, Declarations
569 @comment node-name, next, previous, up
570 @subsection Usage for Package Authors
572 The recommended usage for the author of a typical emacs lisp package is
573 to create one group identifying the package, and make all user options
574 and faces members of that group. If the package has more than around 20
575 such options, they should be divided into a number of subgroups, with
576 each subgroup being member of the top level group.
578 The top level group for the package should itself be member of one or
579 more of the standard customization groups. There exists a group for
580 each @emph{finder} keyword. Press @kbd{C-c p} to see a list of finder
581 keywords, and add you group to each of them, using the @code{:group}
584 @node Utilities, The Init File, Declarations, Top
585 @comment node-name, next, previous, up
588 These utilities can come in handy when adding customization support.
590 @deffn Widget custom-manual
591 Widget type for specifying the info manual entry for a customization
592 option. It takes one argument, an info address.
595 @defun custom-add-to-group group member widget
596 To existing @var{group} add a new @var{member} of type @var{widget},
597 If there already is an entry for that member, overwrite it.
600 @defun custom-add-link symbol widget
601 To the custom option @var{symbol} add the link @var{widget}.
604 @defun custom-add-load symbol load
605 To the custom option @var{symbol} add the dependency @var{load}.
606 @var{load} should be either a library file name, or a feature name.
609 @defun custom-menu-create symbol &optional name
610 Create menu for customization group @var{symbol}.
611 If optional @var{name} is given, use that as the name of the menu.
612 Otherwise make up a name from @var{symbol}.
613 The menu is in a format applicable to @code{easy-menu-define}.
616 @node The Init File, Wishlist, Utilities, Top
617 @comment node-name, next, previous, up
618 @section The Init File
620 When you save the customizations, call to @code{custom-set-variables},
621 @code{custom-set-faces} are inserted into the file specified by
622 @code{custom-file}. By default @code{custom-file} is your @file{.emacs}
623 file. The two functions will initialize variables and faces as you have
626 @node Wishlist, , The Init File, Top
627 @comment node-name, next, previous, up
632 The menu items should be grayed out when the information is
633 missing. I.e. if a variable doesn't have a factory setting, the user
634 should not be allowed to select the @samp{Factory} menu item.
637 We need @strong{much} better support for keyboard operations in the
641 Integrate with @file{w3} so you can customization buffers with much
642 better formatting. I'm thinking about adding a <custom>name</custom>
643 tag. The latest w3 have some support for this, so come up with a
647 Add an `examples' section, with explained examples of custom type
651 Support undo using lmi's @file{gnus-undo.el}.
654 Make it possible to append to `choice', `radio', and `set' options.
657 Ask whether set or modified variables should be saved in
658 @code{kill-buffer-hook}.
660 Ditto for @code{kill-emacs-query-functions}.
663 Command to check if there are any customization options that
664 does not belong to an existing group.
667 Optionally disable the point-cursor and instead highlight the selected
668 item in XEmacs. This is like the *Completions* buffer in XEmacs.
669 Suggested by Jens Lautenbacher
670 @samp{<jens@@lemming0.lem.uni-karlsruhe.de>}.@refill