@c %**start of header
@setfilename ../info/widget
@settitle The Emacs Widget Library
-@ifnottex
-Copyright @copyright{} 2000 Free Software Foundation, Inc.
+@syncodeindex fn cp
+@syncodeindex vr cp
+@syncodeindex ky cp
+@afourpaper
+@c %**end of header
+
+@copying
+Copyright @copyright{} 2000, 2001, 2002, 2003, 2004, 2005,
+2006, 2007, 2008 Free Software Foundation, Inc.
+@quotation
Permission is granted to copy, distribute and/or modify this document
-under the terms of the GNU Free Documentation License, Version 1.1 or
+under the terms of the GNU Free Documentation License, Version 1.2 or
any later version published by the Free Software Foundation; with the
Invariant Sections being ``The GNU Manifesto'', ``Distribution'' and
``GNU GENERAL PUBLIC LICENSE'', with the Front-Cover texts being ``A GNU
(a) The FSF's Back-Cover Text is: ``You have freedom to copy and modify
this GNU Manual, like GNU software. Copies published by the Free
Software Foundation raise funds for GNU development.''
-@end ifnottex
-
-@iftex
-@afourpaper
-@headings double
-@end iftex
-@c %**end of header
-
-@syncodeindex fn cp
-@syncodeindex vr cp
-@syncodeindex ky cp
+@end quotation
+@end copying
@dircategory Emacs
@direntry
-* Widget: (widget). Documenting the "widget" package used by the
- Emacs Custom facility.
+* Widget: (widget). The "widget" package used by the Emacs Customization
+ facility.
@end direntry
@node Top, Introduction, (dir), (dir)
@top The Emacs Widget Library
@menu
-* Introduction::
-* User Interface::
-* Programming Example::
-* Setting Up the Buffer::
-* Basic Types::
-* Sexp Types::
-* Widget Properties::
-* Defining New Widgets::
-* Widget Browser::
-* Widget Minor Mode::
-* Utilities::
-* Widget Wishlist::
+* Introduction::
+* User Interface::
+* Programming Example::
+* Setting Up the Buffer::
+* Basic Types::
+* Sexp Types::
+* Widget Properties::
+* Defining New Widgets::
+* Widget Browser::
+* Widget Minor Mode::
+* Utilities::
+* Widget Wishlist::
+* GNU Free Documentation License::
* Index::
@end menu
@comment node-name, next, previous, up
@section Introduction
-Most graphical user interface toolkits, such as Motif and XView, provide
-a number of standard user interface controls (sometimes known as
-`widgets' or `gadgets'). Emacs doesn't really support anything like
-this, except for an incredibly powerful text ``widget''. On the other
-hand, Emacs does provide the necessary primitives to implement many
-other widgets within a text buffer. The @code{widget} package
-simplifies this task.
+Most graphical user interface toolkits provide a number of standard
+user interface controls (sometimes known as `widgets' or `gadgets').
+Emacs doesn't really support anything like this, except for an
+incredibly powerful text ``widget.'' On the other hand, Emacs does
+provide the necessary primitives to implement many other widgets
+within a text buffer. The @code{widget} package simplifies this task.
@cindex basic widgets
@cindex widgets, basic types
@item link
Areas of text with an associated action. Intended for hypertext links
embedded in text.
-@item push-button
+@item push-button
Like link, but intended for stand-alone buttons.
@item editable-field
An editable text field. It can be either variable or fixed length.
visible in the buffer.
@item item
A simple constant widget intended to be used in the @code{menu-choice} and
-@code{radio-button-choice} widgets.
+@code{radio-button-choice} widgets.
@item choice-item
A button item only intended for use in choices. When invoked, the user
will be asked to select another option from the choice widget.
@item toggle
A simple @samp{on}/@samp{off} switch.
@item checkbox
-A checkbox (@samp{[ ]}/@samp{[X]}).
+A checkbox (@samp{[ ]}/@samp{[X]}).
@item editable-list
Create an editable list. The user can insert or delete items in the
list. Each list item is itself a widget.
meaning. The user is not supposed to change or delete any of the text
between the fields. Examples of forms in Emacs are the @file{forms}
package (of course), the customize buffers, the mail and news compose
-modes, and the @sc{html} form support in the @file{w3} browser.
+modes, and the @acronym{HTML} form support in the @file{w3} browser.
@cindex widget library, why use it
The advantages for a programmer of using the @code{widget} package to
@enumerate
@item
-More complex fields than just editable text are supported.
+More complex fields than just editable text are supported.
@item
You can give the users immediate feedback if they enter invalid data in a
text field, and sometimes prevent entering invalid data.
-@item
+@item
You can have fixed sized fields, thus allowing multiple fields to be
lined up in columns.
@item
-It is simple to query or set the value of a field.
-@item
+It is simple to query or set the value of a field.
+@item
Editing happens in the buffer, not in the mini-buffer.
-@item
+@item
Packages using the library get a uniform look, making them easier for
the user to learn.
-@item
+@item
As support for embedded graphics improve, the widget library will be
extended to use the GUI features. This means that your code using the
widget library will also use the new graphic features automatically.
@end enumerate
-In order to minimize the code that is loaded by users who does not
-create any widgets, the code has been split in two files:
-
-@cindex widget library, files
-@table @file
-@item widget.el
-This will declare the user variables, define the function
-@code{widget-define}, and autoload the function @code{widget-create}.
-@item wid-edit.el
-Everything else is here, there is no reason to load it explicitly, as
-it will be autoloaded when needed.
-@end table
-
@node User Interface, Programming Example, Introduction, Top
@comment node-name, next, previous, up
@section User Interface
-A form consist of read only text for documentation and some fields,
+A form consists of read only text for documentation and some fields,
where each field contains two parts, a tag and a value. The tags are
used to identify the fields, so the documentation can refer to the
@samp{foo field}, meaning the field tagged with @samp{Foo}. Here is an
See also @b{_other work_} for more information.
Numbers: count to three below
-@b{+/-} @i{One}
-@b{+/-} @i{Eh, two?}
-@b{+/-} @i{Five!}
-@b{+}
+@b{[INS]} @b{[DEL]} @i{One}
+@b{[INS]} @b{[DEL]} @i{Eh, two?}
+@b{[INS]} @b{[DEL]} @i{Five!}
+@b{[INS]}
Select multiple:
@b{[Apply Form]} @b{[Reset Form]}
@end example
-The top level widgets in is example are tagged @samp{Name},
+The top level widgets in this example are tagged @samp{Name},
@samp{Choose}, @samp{Address}, @samp{_other work_}, @samp{Numbers},
@samp{Select multiple}, @samp{Select one}, @samp{[Apply Form]}, and
@samp{[Reset Form]}. There are basically two things the user can do
For example, capitalizing all text from the middle of one field to the
middle of another field is prohibited.
-Editing text fields are created by the @code{editable-field} widget.
+Editable text fields are created by the @code{editable-field} widget.
+
+@strong{Warning:} In an @code{editable-field} widget, the editable
+field must not be adjacent to another widget---that won't work.
+You must put some text in between. Either make this text part of
+the @code{editable-field} widget itself, or insert it with
+@code{widget-insert}.
+
+The @code{:format} keyword is useful for generating the necessary
+text; for instance, if you give it a value of @code{"Name: %v "},
+the @samp{Name: } part will provide the necessary separating text
+before the field and the trailing space will provide the
+separating text after the field. If you don't include the
+@code{:size} keyword, the field will extend to the end of the
+line, and the terminating newline will provide separation after.
+
+@strong{Warning:} In an @code{editable-field} widget, the @samp{%v} escape
+must be preceded by some other text in the @code{:format} string
+(if specified).
The editing text fields are highlighted with the
@code{widget-field-face} face, making them easy to find.
@code{widget-global-map} (by default the global map).
@end deffn
-@kindex mouse-2, on button widgets
-@item mouse-2
+@kindex Mouse-2 @r{(on button widgets})
+@item Mouse-2
@deffn Command widget-button-click @var{event}
Invoke the button at the location of the mouse pointer. If the mouse
pointer is located in an editable text field, invoke the binding in
between a number of different options. This is how you edit an option
field. Option fields are created by the @code{menu-choice} widget. In
the example, @samp{@b{Choose}} is an option field tag.
-@item The @samp{@b{+/-}} buttons
+@item The @samp{@b{[INS]}} and @samp{@b{[DEL]}} buttons
Activating these will insert or delete elements from an editable list.
-The list is created by the @code{editable-list} widget.
+The list is created by the @code{editable-list} widget.
@cindex embedded buttons
@item Embedded Buttons
The @samp{@b{_other work_}} is an example of an embedded
-button. Embedded buttons are not associated with a fields, but can serve
+button. Embedded buttons are not associated with any fields, but can serve
any purpose, such as implementing hypertext references. They are
usually created by the @code{link} widget.
@item The @samp{@b{[ ]}} and @samp{@b{[X]}} buttons
Activating one of these will convert it to the other. This is useful
-for implementing multiple-choice fields. You can create it with the
+for implementing multiple-choice fields. You can create them with the
@code{checkbox} widget.
@item The @samp{@b{( )}} and @samp{@b{(*)}} buttons
Only one radio button in a @code{radio-button-choice} widget can be
selected at any time. When you invoke one of the unselected radio
buttons, it will be selected and the previous selected radio button will
become unselected.
-@item The @samp{@b{[Apply Form]}} @samp{@b{[Reset Form]}} buttons
+@item The @samp{@b{[Apply Form]}} and @samp{@b{[Reset Form]}} buttons
These are explicit buttons made with the @code{push-button} widget. The
main difference from the @code{link} widget is that the buttons will be
displayed as GUI buttons when possible.
@end table
-To make them easier to locate, buttons are emphasized in the buffer.
+To make them easier to locate, buttons are emphasized in the buffer.
@deffn Face widget-button-face
Face used for buttons.
@deffn Command widget-forward &optional count
Move point @var{count} buttons or editing fields forward.
@end deffn
-@item @key{M-TAB}
+@item @kbd{M-@key{TAB}}
+@itemx @kbd{S-@key{TAB}}
@deffn Command widget-backward &optional count
Move point @var{count} buttons or editing fields backward.
@end deffn
(make-local-variable 'widget-example-repeat)
(let ((inhibit-read-only t))
(erase-buffer))
- (widget-insert "Here is some documentation.\n\nName: ")
+ (remove-overlays)
+ (widget-insert "Here is some documentation.\n\n")
(widget-create 'editable-field
:size 13
+ :format "Name: %v " ; Text after the field!
"My Name")
(widget-create 'menu-choice
:tag "Choose"
'(item :tag "This option" :value "This")
'(choice-item "That option")
'(editable-field :menu-tag "No option" "Thus option"))
- (widget-insert "Address: ")
(widget-create 'editable-field
+ :format "Address: %v"
"Some Place\nIn some City\nSome country.")
(widget-insert "\nSee also ")
(widget-create 'link
:notify (lambda (&rest ignore)
- (widget-value-set widget-example-repeat
+ (widget-value-set widget-example-repeat
'("En" "To" "Tre"))
(widget-setup))
"other work")
- (widget-insert " for more information.\n\nNumbers: count to three below\n")
+ (widget-insert
+ " for more information.\n\nNumbers: count to three below\n")
(setq widget-example-repeat
(widget-create 'editable-list
:entry-format "%i %d %v"
'(item "One") '(item "Another One.") '(item "A Final One."))
(widget-insert "\n")
(widget-create 'push-button
- :notify (lambda (&rest ignore)
+ :notify (lambda (&rest ignore)
(if (= (length (widget-value widget-example-repeat))
3)
(message "Congratulation!")
Delete @var{widget} and remove it from the buffer.
@end defun
-@defun widget-setup
-Set up a buffer to support widgets.
+@defun widget-setup
+Set up a buffer to support widgets.
This should be called after creating all the widgets and before allowing
the user to edit them.
If you want to insert text outside the widgets in the form, the
recommended way to do that is with @code{widget-insert}.
-@defun widget-insert
+@defun widget-insert
Insert the arguments, either strings or characters, at point.
The inserted text will be read-only.
@end defun
@defvr Const widget-keymap
A keymap with the global keymap as its parent.@*
@key{TAB} and @kbd{C-@key{TAB}} are bound to @code{widget-forward} and
-@code{widget-backward}, respectively. @kbd{@key{RET}} and @kbd{mouse-2}
+@code{widget-backward}, respectively. @key{RET} and @kbd{Mouse-2}
are bound to @code{widget-button-press} and
@code{widget-button-click}.@refill
@end defvr
@comment node-name, next, previous, up
@section Basic Types
-The syntax of a type specification is given below:
+This is the general syntax of a type specification:
@example
-NAME ::= (NAME [KEYWORD ARGUMENT]... ARGS)
- | NAME
+@var{name} ::= (@var{name} [@var{keyword} @var{argument}]... @var{args})
+ | @var{name}
@end example
Where, @var{name} is a widget name, @var{keyword} is the name of a
are interpreted in a widget specific way.
@cindex keyword arguments
-The following keyword arguments that apply to all widgets:
+The following keyword arguments apply to all widgets:
@table @code
@vindex value@r{ keyword}
The text inside will be marked as a button.
By default, the text will be shown in @code{widget-button-face}, and
-surrounded by brackets.
+surrounded by brackets.
@defopt widget-button-prefix
String to prefix buttons.
@item %@{
@itemx %@}
The text inside will be displayed with the face specified by
-@code{:sample-face}.
+@code{:sample-face}.
@item %v
This will be replaced with the buffer representation of the widget's
value. What this is depends on the widget type.
+@strong{Warning:} In an @code{editable-field} widget, the @samp{%v} escape
+must be preceded by some other text in the format string (if specified).
+
@item %d
Insert the string specified by @code{:doc} here.
representation of the value if there is no tag.
@item %%
-Insert a literal @samp{%}.
+Insert a literal @samp{%}.
@end table
@vindex button-face@r{ keyword}
@vindex doc@r{ keyword}
@item :doc
The string inserted by the @samp{%d} escape in the format
-string.
+string.
@vindex tag@r{ keyword}
@item :tag
The string inserted by the @samp{%t} escape in the format
-string.
+string.
@vindex tag-glyph@r{ keyword}
@item :tag-glyph
Specifies how to display a message whenever you move to the widget with
either @code{widget-forward} or @code{widget-backward} or move the mouse
over it (using the standard @code{help-echo} mechanism). The argument
-is either a string to display or a function of one argument, the widget,
-which should return a string to display.
+is either a string to display, a function of one argument, the widget,
+which should return a string to display, or a form that evaluates to
+such a string.
+
+@vindex follow-link@r{ keyword}
+@item :follow-link
+Specifies how to interpret a @key{mouse-1} click on the widget.
+@xref{Links and Mouse-1,,, elisp, the Emacs Lisp Reference Manual}.
@vindex indent@r{ keyword}
@item :indent
The function is called with two or three arguments. The first argument
is the widget itself, the second argument is the widget that was
changed, and the third argument is the event leading to the change, if
-any.
+any.
@vindex menu-tag@r{ keyword}
@item :menu-tag
@vindex match@r{ keyword}
@item :match
Should be a function called with two arguments, the widget and a value,
-and returning non-nil if the widget can represent the specified value.
+and returning non-@code{nil} if the widget can represent the specified value.
@vindex validate@r{ keyword}
@item :validate
@item
Widgets with tabbing order @code{-1} are ignored.
-@item
+@item
(Unimplemented) When on a widget with tabbing order @var{n}, go to the
next widget in the buffer with tabbing order @var{n+1} or @code{nil},
whichever comes first.
@end table
@deffn {User Option} widget-glyph-directory
-Directory where glyphs are found.
+Directory where glyphs are found.
Widget will look here for a file with the same name as specified for the
image, with either a @file{.xpm} (if supported) or @file{.xbm} extension.
@end deffn
@deffn{User Option} widget-glyph-enable
-If non-nil, allow glyphs to appear on displays where they are supported.
+If non-@code{nil}, allow glyphs to appear on displays where they are supported.
@end deffn
@menu
-* link::
-* url-link::
-* info-link::
-* push-button::
-* editable-field::
-* text::
-* menu-choice::
-* radio-button-choice::
-* item::
-* choice-item::
-* toggle::
-* checkbox::
-* checklist::
-* editable-list::
-* group::
+* link::
+* url-link::
+* info-link::
+* push-button::
+* editable-field::
+* text::
+* menu-choice::
+* radio-button-choice::
+* item::
+* choice-item::
+* toggle::
+* checkbox::
+* checklist::
+* editable-list::
+* group::
@end menu
@node link, url-link, Basic Types, Basic Types
Syntax:
@example
-TYPE ::= (link [KEYWORD ARGUMENT]... [ VALUE ])
+@var{type} ::= (link [@var{keyword} @var{argument}]... [ @var{value} ])
@end example
The @var{value}, if present, is used to initialize the @code{:value}
property. The value should be a string, which will be inserted in the
-buffer.
+buffer.
By default the link will be shown in brackets.
Syntax:
@example
-TYPE ::= (url-link [KEYWORD ARGUMENT]... URL)
+@var{type} ::= (url-link [@var{keyword} @var{argument}]... @var{url})
@end example
@findex browse-url-browser-function@r{, and @code{url-link} widget}
-When this link is invoked, the @sc{www} browser specified by
-@code{browse-url-browser-function} will be called with @var{url}.
+When this link is invoked, the @acronym{WWW} browser specified by
+@code{browse-url-browser-function} will be called with @var{url}.
@node info-link, push-button, url-link, Basic Types
@comment node-name, next, previous, up
Syntax:
@example
-TYPE ::= (info-link [KEYWORD ARGUMENT]... ADDRESS)
+@var{type} ::= (info-link [@var{keyword} @var{argument}]... @var{address})
@end example
When this link is invoked, the built-in Info reader is started on
-@var{address}.
+@var{address}.
@node push-button, editable-field, info-link, Basic Types
@comment node-name, next, previous, up
Syntax:
@example
-TYPE ::= (push-button [KEYWORD ARGUMENT]... [ VALUE ])
+@var{type} ::= (push-button [@var{keyword} @var{argument}]... [ @var{value} ])
@end example
The @var{value}, if present, is used to initialize the @code{:value}
property. The value should be a string, which will be inserted in the
-buffer.
+buffer.
By default the tag will be shown in brackets.
Syntax:
@example
-TYPE ::= (editable-field [KEYWORD ARGUMENT]... [ VALUE ])
+@var{type} ::= (editable-field [@var{keyword} @var{argument}]... [ @var{value} ])
@end example
The @var{value}, if present, is used to initialize the @code{:value}
-property. The value should be a string, which will be inserted in
+property. The value should be a string, which will be inserted in the
field. This widget will match all string values.
The following extra properties are recognized:
@vindex value-face@r{ keyword}
@item :value-face
Face used for highlighting the editable field. Default is
-@code{widget-field-face}, see @ref{User Interface}.
+@code{widget-field-face}, see @ref{User Interface}.
@vindex secret@r{ keyword}
@item :secret
Character used to display the value. You can set this to e.g.@: @code{?*}
if the field contains a password or other secret information. By
-default, this is nil, and the value is not secret.
+default, this is @code{nil}, and the value is not secret.
@vindex valid-regexp@r{ keyword}
@item :valid-regexp
Syntax:
@example
-TYPE ::= (menu-choice [KEYWORD ARGUMENT]... TYPE ... )
+@var{type} ::= (menu-choice [@var{keyword} @var{argument}]... @var{type} ... )
@end example
The @var{type} argument represents each possible choice. The widget's
@table @code
@vindex void@r{ keyword}
-@item :void
+@item :void
Widget type used as a fallback when the value does not match any of the
specified @var{type} arguments.
@vindex case-fold@r{ keyword}
@item :case-fold
-Set this to nil if you don't want to ignore case when prompting for a
+Set this to @code{nil} if you don't want to ignore case when prompting for a
choice through the minibuffer.
@vindex children@r{ keyword}
@item :children
-A list whose @code{car} is the widget representing the currently chosen
+A list whose @sc{car} is the widget representing the currently chosen
type in the buffer.
@vindex choice@r{ keyword}
The current chosen type.
@vindex args@r{ keyword}
-@item :args
-The list of types.
+@item :args
+The list of types.
@end table
@node radio-button-choice, item, menu-choice, Basic Types
Syntax:
@example
-TYPE ::= (radio-button-choice [KEYWORD ARGUMENT]... TYPE ... )
+@var{type} ::= (radio-button-choice [@var{keyword} @var{argument}]... @var{type} ... )
@end example
-The @var{type} argument represents each possible choice. The widget's
-value will be that of the chosen @var{type} argument. This widget will
-match any value matching at least one of the specified @var{type}
-arguments.
+The component types specify the choices, with one radio button for
+each. The widget's value will be that of the chosen @var{type}
+argument. This widget matches any value that matches at least one of
+the specified @var{type} arguments.
The following extra properties are recognized.
@item %b
Replace with the radio button.
@item %%
-Insert a literal @samp{%}.
+Insert a literal @samp{%}.
@end table
@vindex button-args@r{ keyword}
The current chosen type
@vindex args@r{ keyword}
-@item :args
-The list of types.
+@item :args
+The list of types.
@end table
You can add extra radio button items to a @code{radio-button-choice}
widget after it has been created with the function
-@code{widget-radio-add-item}.
+@code{widget-radio-add-item}.
@defun widget-radio-add-item widget type
Add to @code{radio-button-choice} widget @var{widget} a new radio button
Syntax:
@example
-ITEM ::= (item [KEYWORD ARGUMENT]... VALUE)
+@var{item} ::= (item [@var{keyword} @var{argument}]... @var{value})
@end example
The @var{value}, if present, is used to initialize the @code{:value}
Syntax:
@example
-ITEM ::= (choice-item [KEYWORD ARGUMENT]... VALUE)
+@var{item} ::= (choice-item [@var{keyword} @var{argument}]... @var{value})
@end example
The @var{value}, if present, is used to initialize the @code{:value}
property. The value should be a string, which will be inserted in the
buffer as a button. Activating the button of a @code{choice-item} is
equivalent to activating the parent widget. This widget will only match
-the specified value.
+the specified value.
@node toggle, checkbox, choice-item, Basic Types
@comment node-name, next, previous, up
Syntax:
@example
-TYPE ::= (toggle [KEYWORD ARGUMENT]...)
+@var{type} ::= (toggle [@var{keyword} @var{argument}]...)
@end example
The widget has two possible states, @samp{on} and @samp{off}, which
@item :on
A string representing the @samp{on} state. By default the string
@samp{on}.
-@item :off
+@item :off
A string representing the @samp{off} state. By default the string
@samp{off}.
@vindex on-glyph@r{ keyword}
Syntax:
@example
-TYPE ::= (checkbox [KEYWORD ARGUMENT]...)
+@var{type} ::= (checkbox [@var{keyword} @var{argument}]...)
@end example
@node checklist, editable-list, checkbox, Basic Types
Syntax:
@example
-TYPE ::= (checklist [KEYWORD ARGUMENT]... TYPE ... )
+@var{type} ::= (checklist [@var{keyword} @var{argument}]... @var{type} ... )
@end example
The @var{type} arguments represent each checklist item. The widget's
@item %b
Replace with the checkbox.
@item %%
-Insert a literal @samp{%}.
+Insert a literal @samp{%}.
@end table
@vindex greedy@r{ keyword}
@item :greedy
Usually a checklist will only match if the items are in the exact
sequence given in the specification. By setting @code{:greedy} to
-non-nil, it will allow the items to come in any sequence. However, if
-you extract the value they will be in the sequence given in the
-checklist, i.e.@: the original sequence is forgotten.
+non-@code{nil}, it will allow the items to come in any sequence.
+However, if you extract the value they will be in the sequence given
+in the checklist, i.e.@: the original sequence is forgotten.
@vindex button-args@r{ keyword}
@item :button-args
The widgets representing each type.
@vindex args@r{ keyword}
-@item :args
-The list of types.
+@item :args
+The list of types.
@end table
@node editable-list, group, checklist, Basic Types
Syntax:
@example
-TYPE ::= (editable-list [KEYWORD ARGUMENT]... TYPE)
+@var{type} ::= (editable-list [@var{keyword} @var{argument}]... @var{type})
@end example
The value is a list, where each member represents one widget of type
-@var{type}.
+@var{type}.
The following extra properties are recognized:
@item %v
This will be replaced with the buffer representation of the @var{type}
widget.
-@item %-
-Insert the @b{+/-} button.
@item %i
-Insert the @b{+} button at the end of a list.
+Insert the @b{[INS]} button.
@item %d
Insert the @b{[DEL]} button.
@item %%
-Insert a literal @samp{%}.
+Insert a literal @samp{%}.
@end table
-@vindex insert/delete-button-args@r{ keyword}
-@item :insert/delete-button-args
+@vindex insert-button-args@r{ keyword}
+@item :insert-button-args
A list of keyword arguments to pass to the insert buttons.
@vindex delete-button-args@r{ keyword}
@vindex args@r{ keyword}
@item :args
-List whose @code{car} is the type of the list elements.
+List whose @sc{car} is the type of the list elements.
@end table
@node group, , editable-list, Basic Types
Syntax:
@example
-TYPE ::= (group [KEYWORD ARGUMENT]... TYPE...)
+@var{type} ::= (group [@var{keyword} @var{argument}]... @var{type}...)
@end example
-The value is a list, with one member for each @var{type}.
+The value is a list, with one member for each @var{type}.
@node Sexp Types, Widget Properties, Basic Types, Top
@comment
@section Sexp Types
@cindex sexp types
-A number of widgets for editing @dfn{s-expressions} (lisp types), sexp
+A number of widgets for editing @dfn{s-expressions} (Lisp types), sexp
for short, are also available. These basically fall in several
categories described in this section.
@menu
-* constants::
-* generic::
-* atoms::
-* composite::
+* constants::
+* generic::
+* atoms::
+* composite::
@end menu
@node constants, generic, Sexp Types, Sexp Types
@subsection The Constant Widgets
@cindex constant widgets
-The @code{const} widget can contain any lisp expression, but the user is
+The @code{const} widget can contain any Lisp expression, but the user is
prohibited from editing it, which is mainly useful as a component of one
of the composite widgets.
The syntax for the @code{const} widget is:
@example
-TYPE ::= (const [KEYWORD ARGUMENT]... [ VALUE ])
+@var{type} ::= (const [@var{keyword} @var{argument}]... [ @var{value} ])
@end example
The @var{value}, if present, is used to initialize the @code{:value}
@deffn Widget const
This will display any valid s-expression in an immutable part of the
-buffer.
+buffer.
@end deffn
There are two variations of the @code{const} widget, namely
@subsection Generic Sexp Widget
@cindex generic sexp widget
-The @code{sexp} widget can contain any lisp expression, and allows the
+The @code{sexp} widget can contain any Lisp expression, and allows the
user to edit it inline in the buffer.
The syntax for the @code{sexp} widget is:
@example
-TYPE ::= (sexp [KEYWORD ARGUMENT]... [ VALUE ])
+@var{type} ::= (sexp [@var{keyword} @var{argument}]... [ @var{value} ])
@end example
@deffn Widget sexp
This will allow you to edit any valid s-expression in an editable buffer
-field.
+field.
The @code{sexp} widget takes the same keyword arguments as the
@code{editable-field} widget. @xref{editable-field}.
The syntax for all the atoms are:
@example
-TYPE ::= (NAME [KEYWORD ARGUMENT]... [ VALUE ])
+@var{type} ::= (@var{construct} [@var{keyword} @var{argument}]... [ @var{value} ])
@end example
The @var{value}, if present, is used to initialize the @code{:value}
@end deffn
@deffn Widget file
-Allows you to edit a file name in an editable field. If you invoke
-the tag button, you can edit the file name in the mini-buffer with
-completion.
+Allows you to edit a file name in an editable field.
Keywords:
@table @code
@vindex must-match@r{ keyword}
@item :must-match
-If this is set to non-nil, only existing file names will be allowed in
-the minibuffer.
+If this is set to non-@code{nil}, only existing file names will be
+allowed in the minibuffer.
@end table
@end deffn
@end deffn
@deffn Widget symbol
-Allows you to edit a lisp symbol in an editable field.
+Allows you to edit a Lisp symbol in an editable field.
@end deffn
@deffn Widget function
@end deffn
@deffn Widget boolean
-Allows you to edit a boolean. In lisp this means a variable which is
-either nil meaning false, or non-nil meaning true.
+Allows you to edit a boolean. In Lisp this means a variable which is
+either @code{nil} meaning false, or non-@code{nil} meaning true.
@end deffn
@subsection Composite Sexp Widgets
@cindex composite sexp widgets
-The syntax for the composite widget is:
+The syntax for the composite widget construct is:
@example
-TYPE ::= (NAME [KEYWORD ARGUMENT]... COMPONENT...)
+@var{type} ::= (@var{construct} [@var{keyword} @var{argument}]... @var{component}...)
@end example
@noindent
will be displayed in the buffer, and will be editable by the user.
@deffn Widget cons
-The value of a @code{cons} widget is a cons-cell where the @code{car} is
-the value of the first component and the @code{cdr} is the value of the
-second component. There must be exactly two components.
+The value of a @code{cons} widget must be a cons-cell whose @sc{car}
+and @sc{cdr} have two specified types. It uses this syntax:
+
+@example
+@var{type} ::= (cons [@var{keyword} @var{argument}]... @var{car-type} @var{cdr-type})
+@end example
+@end deffn
+
+@deffn Widget choice
+The value matched by a @code{choice} widget must have one of a fixed
+set of types. The widget's syntax is as follows:
+
+@example
+@var{type} ::= (choice [@var{keyword} @var{argument}]... @var{type} ... )
+@end example
+
+The value of a @code{choice} widget can be anything that matches any of the
+@var{types}.
@end deffn
@deffn Widget list
-The value of a @code{list} widget is a list containing the value of
-each of its component.
+The value of a @code{list} widget must be a list whose element types
+match the specified component types:
+
+@example
+@var{type} ::= (list [@var{keyword} @var{argument}]... @var{component-type}...)
+@end example
+
+Thus, @code{(list string number)} matches lists of two elements,
+the first being a string and the second being a number.
@end deffn
@deffn Widget vector
-The value of a @code{vector} widget is a vector containing the value of
-each of its component.
+The @code{vector} widget is like the @code{list} widget but matches
+vectors instead of lists. Thus, @code{(vector string number)} matches
+vectors of two elements, the first being a string and the second being
+a number.
@end deffn
The above suffice for specifying fixed size lists and vectors. To get
variable length lists and vectors, you can use a @code{choice},
-@code{set}, or @code{repeat} widgets together with the @code{:inline}
-keywords. If any component of a composite widget has the @code{:inline}
-keyword set, its value must be a list which will then be spliced into
-the composite. For example, to specify a list whose first element must
-be a file name, and whose remaining arguments should either by the
-symbol @code{t} or two files, you can use the following widget
-specification:
+@code{set}, or @code{repeat} widget together with the @code{:inline}
+keyword. If any component of a composite widget has the
+@code{:inline} keyword set, its value must be a list which will then
+be spliced into the composite. For example, to specify a list whose
+first element must be a file name, and whose remaining elements should
+either be the symbol @code{t} or two strings (file names), you can use
+the following widget specification:
@example
(list file
string string)))
@end example
-The value of a widget of this type will either have the form
-@code{(file t)} or @code{(file string string)}.
+The value of a widget of this type will either have the form
+@code{(file t)} or @code{(file @var{string} @var{string})}.
-This concept of inline is probably hard to understand. It was certainly
-hard to implement, so instead of confusing you more by trying to explain
-it here, I'll just suggest you meditate over it for a while.
-
-@deffn Widget choice
-Allows you to edit a sexp which may have one of a fixed set of types.
-It is currently implemented with the @code{choice-menu} basic widget,
-and has a similar syntax.
-@end deffn
+This concept of @code{:inline} may be hard to understand. It was
+certainly hard to implement, so instead of confusing you more by
+trying to explain it here, I'll just suggest you meditate over it for
+a while.
@deffn Widget set
-Allows you to specify a type which must be a list whose elements all
-belong to given set. The elements of the list are not significant.
-This is implemented on top of the @code{checklist} basic widget, and has
-a similar syntax.
+Specifies a type whose values are the lists whose elements all belong
+to a given set. The order of elements of the list is not significant.
+Here's the syntax:
+
+@example
+@var{type} ::= (set [@var{keyword} @var{argument}]... @var{permitted-element} ... )
+@end example
+
+Use @code{const} to specify each permitted element, like this:
+@code{(set (const a) (const b))}.
@end deffn
@deffn Widget repeat
-Allows you to specify a variable length list whose members are all of
-the same type. Implemented on top of the @code{editable-list} basic
-widget, and has a similar syntax.
+Specifies a list of any number of elements that fit a certain type.
+
+@example
+@var{type} ::= (repeat [@var{keyword} @var{argument}]... @var{type})
+@end example
@end deffn
@node Widget Properties, Defining New Widgets, Sexp Types, Top
widget again. It is enough to call @code{widget-setup} once if you
modify multiple widgets. This is currently only necessary if the widget
contains an editing field, but may be necessary for other widgets in the
-future.
+future.
If your application needs to associate some information with the widget
objects, for example a reference to the item being edited, it can be
@end defun
@defun widget-member widget property
-Non-nil if @var{widget} has a value (even nil) for property @var{property}.
+Non-@code{nil} if @var{widget} has a value (even @code{nil}) for
+property @var{property}.
@end defun
Occasionally it can be useful to know which kind of widget you have,
-i.e.@: the name of the widget type you gave when the widget was created.
+i.e.@: the name of the widget type you gave when the widget was created.
@defun widget-type widget
Return the name of @var{widget}, a symbol.
all its ancestors.
@lisp
-(while widget
+(while widget
(widget-apply widget :activate)
(setq widget (widget-get widget :parent)))
@end lisp
You can check if a widget has been made inactive by examining the value
-of the @code{:inactive} keyword. If this is non-nil, the widget itself
+of the @code{:inactive} keyword. If this is non-@code{nil}, the widget itself
has been deactivated. This is different from using the @code{:active}
keyword, in that the latter tells you if the widget @strong{or} any of
its ancestors have been deactivated. Do not attempt to set the
@cindex new widgets
@cindex defining new widgets
-You can define specialized widgets with @code{widget-define}. It allows
+You can define specialized widgets with @code{define-widget}. It allows
you to create a shorthand for more complex widgets, including specifying
component widgets and new default values for the keyword
-arguments.
+arguments.
-@defun widget-define name class doc &rest args
+@defun define-widget name class doc &rest args
Define a new widget type named @var{name} from @code{class}.
@var{name} and class should both be symbols, @code{class} should be one
-of the existing widget types.
+of the existing widget types.
-The third argument @var{DOC} is a documentation string for the widget.
+The third argument @var{doc} is a documentation string for the widget.
After the new widget has been defined, the following two calls will
create identical widgets:
@end defun
-Using @code{widget-define} just stores the definition of the widget type
+Using @code{define-widget} just stores the definition of the widget type
in the @code{widget-type} property of @var{name}, which is what
@code{widget-create} uses.
conversions, you can use @code{identity} as your conversion function.
The following additional keyword arguments are useful when defining new
-widgets:
+widgets:
@table @code
@vindex convert-widget@r{ keyword}
@item :convert-widget
Function to convert a widget type before creating a widget of that
type. It takes a widget type as an argument, and returns the converted
widget type. When a widget is created, this function is called for the
-widget type and all the widget's parent types, most derived first.
+widget type and all the widget's parent types, most derived first.
The following predefined functions can be used here:
Initialize @code{:value} from @code{:args} in @var{widget}.
@end defun
+@vindex copy@r{ keyword}
+@item :copy
+Function to deep copy a widget type. It takes a shallow copy of the
+widget type as an argument (made by @code{copy-sequence}), and returns a
+deep copy. The purpose of this is to avoid having different instances
+of combined widgets share nested attributes.
+
+The following predefined functions can be used here:
+
+@defun widget-types-copy widget
+Copy @code{:args} as widget types in @var{widget}.
+@end defun
+
@vindex value-to-internal@r{ keyword}
@item :value-to-internal
Function to convert the value to the internal format. The function
Function to delete a widget. The function takes one argument, a widget,
and should remove all traces of the widget from the buffer.
+The default value is:
+
+@defun widget-default-delete widget
+Remove @var{widget} from the buffer.
+Delete all @code{:children} and @code{:buttons} in @var{widget}.
+@end defun
+
+In most cases you should not change this value, but instead use
+@code{:value-delete} to make any additional cleanup.
+
@vindex value-create@r{ keyword}
@item :value-create
Function to expand the @samp{%v} escape in the format string. It will
be called with the widget as its argument and should insert a
representation of the widget's value in the buffer.
+Nested widgets should be listed in @code{:children} or @code{:buttons}
+to make sure they are automatically deleted.
+
@vindex value-delete@r{ keyword}
@item :value-delete
Should remove the representation of the widget's value from the buffer.
It will be called with the widget as its argument. It doesn't have to
remove the text, but it should release markers and delete nested widgets
-if such have been used.
-
-The following predefined function can be used here:
-
-@defun widget-children-value-delete widget
-Delete all @code{:children} and @code{:buttons} in @var{widget}.
-@end defun
+if these are not listed in @code{:children} or @code{:buttons}.
@vindex value-get@r{ keyword}
-@item :value-get
+@item :value-get
Function to extract the value of a widget, as it is displayed in the
-buffer.
+buffer.
The following predefined function can be used here:
@vindex action@r{ keyword}
@item :action
Function to handle user initiated events. By default, @code{:notify}
-the parent.
+the parent.
The following predefined function can be used here:
take four arguments, @var{widget}, @var{prompt}, @var{value}, and
@var{unbound} and should return a value for widget entered by the user.
@var{prompt} is the prompt to use. @var{value} is the default value to
-use, unless @var{unbound} is non-nil, in which case there is no default
+use, unless @var{unbound} is non-@code{nil}, in which case there is no default
value. The function should read the value using the method most natural
for this widget, and does not have to check that it matches.
@end table
If you want to define a new widget from scratch, use the @code{default}
widget as its base.
-@deffn Widget default
-Widget used as a base for other widgets.
+@deffn Widget default
+Widget used as a base for other widgets.
It provides most of the functionality that is referred to as ``by
-default'' in this text.
+default'' in this text.
@end deffn
@node Widget Browser, Widget Minor Mode, Defining New Widgets, Top
shows the value of each keyword, but uses links for certain keywords
such as @samp{:parent}, which avoids printing cyclic structures.
-@deffn Command widget-browse WIDGET
-Create a widget browser for WIDGET.
-When called interactively, prompt for WIDGET.
+@deffn Command widget-browse @var{widget}
+Create a widget browser for @var{widget}.
+When called interactively, prompt for @var{widget}.
@end deffn
-@deffn Command widget-browse-other-window WIDGET
-Create a widget browser for WIDGET and show it in another window.
-When called interactively, prompt for WIDGET.
+@deffn Command widget-browse-other-window @var{widget}
+Create a widget browser for @var{widget} and show it in another window.
+When called interactively, prompt for @var{widget}.
@end deffn
-@deffn Command widget-browse-at POS
-Create a widget browser for the widget at POS.
+@deffn Command widget-browse-at @var{pos}
+Create a widget browser for the widget at @var{pos}.
When called interactively, use the position of point.
@end deffn
There is a minor mode for manipulating widgets in major modes that
don't provide any support for widgets themselves. This is mostly
-intended to be useful for programmers doing experiments.
+intended to be useful for programmers doing experiments.
@deffn Command widget-minor-mode
Toggle minor mode for traversing widgets.
@defun widget-prompt-value widget prompt [ value unbound ]
Prompt for a value matching @var{widget}, using @var{prompt}.
The current value is assumed to be @var{value}, unless @var{unbound} is
-non-nil.@refill
+non-@code{nil}.@refill
@end defun
@defun widget-get-sibling widget
This is only meaningful for radio buttons or checkboxes in a list.
@end defun
-@node Widget Wishlist, Index, Utilities, Top
+@node Widget Wishlist, GNU Free Documentation License, Utilities, Top
@comment node-name, next, previous, up
@section Wishlist
@cindex todo
@itemize @bullet
-@item
+@item
It should be possible to add or remove items from a list with @kbd{C-k}
and @kbd{C-o} (suggested by @sc{rms}).
+@item
+The @samp{[INS]} and @samp{[DEL]} buttons should be replaced by a single
+dash (@samp{-}). The dash should be a button that, when invoked, asks
+whether you want to add or delete an item (@sc{rms} wanted to git rid of
+the ugly buttons, the dash is my idea).
+
@item
The @code{menu-choice} tag should be prettier, something like the abbreviated
menus in Open Look.
@item
Add commands to show overview of object and class hierarchies to the
-browser.
+browser.
-@item
+@item
Find a way to disable mouse highlight for inactive widgets.
@item
Find a way to make glyphs look inactive.
+@item
+Add @code{property-list} widget.
+
+@item
+Add @code{association-list} widget.
+
@item
Add @code{key-binding} widget.
Find clean way to implement variable length list.
See @code{TeX-printer-list} for an explanation.
-@item
+@item
@kbd{C-h} in @code{widget-prompt-value} should give type specific help.
-@item
+@item
Add a @code{mailto} widget.
@end itemize
-@node Index, , Widget Wishlist, Top
+@node GNU Free Documentation License, Index, Widget Wishlist, Top
+@appendix GNU Free Documentation License
+@include doclicense.texi
+
+@node Index, , GNU Free Documentation License, Top
@comment node-name, next, previous, up
@unnumbered Index
@setchapternewpage odd
@contents
@bye
+
+@ignore
+ arch-tag: 2b427731-4c61-4e72-85de-5ccec9c623f0
+@end ignore