The Emacs Widget Library 1 Introduction 2 User Interface 2.1 Editable Text Fields 2.2 Buttons 2.3 Navigation 3 Programming Example 4 Setting Up the Buffer 5 Basic Types 5.1 The ‘link’ Widget 5.2 The ‘url-link’ Widget 5.3 The ‘info-link’ Widget 5.4 The ‘push-button’ Widget 5.5 The ‘editable-field’ Widget 5.6 The ‘text’ Widget 5.7 The ‘menu-choice’ Widget 5.8 The ‘radio-button-choice’ Widget 5.9 The ‘item’ Widget 5.10 The ‘choice-item’ Widget 5.11 The ‘toggle’ Widget 5.12 The ‘checkbox’ Widget 5.13 The ‘checklist’ Widget 5.14 The ‘editable-list’ Widget 5.15 The ‘group’ Widget 6 Sexp Types 6.1 The Constant Widgets 6.2 Generic Sexp Widget 6.3 Atomic Sexp Widgets 6.4 Composite Sexp Widgets 7 Properties 8 Defining New Widgets 9 Widget Browser 10 Widget Minor Mode 11 Utilities 12 Wishlist Appendix A GNU Free Documentation License Index The Emacs Widget Library ************************ Copyright © 2000–2023 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual”, and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License”. (a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.” 1 Introduction ************** 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 ‘widget’ package simplifies this task. The basic widgets are: ‘link’ Areas of text with an associated action. Intended for hypertext links embedded in text. ‘push-button’ Like link, but intended for stand-alone buttons. ‘editable-field’ An editable text field. It can be either variable or fixed length. ‘menu-choice’ Allows the user to choose one of multiple options from a menu, each option is itself a widget. Only the selected option will be visible in the buffer. ‘radio-button-choice’ Allows the user to choose one of multiple options by activating radio buttons. The options are implemented as widgets. All options will be visible in the buffer. ‘item’ A simple constant widget intended to be used in the ‘menu-choice’ and ‘radio-button-choice’ widgets. ‘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. ‘toggle’ A simple ‘on’/‘off’ switch. ‘checkbox’ A checkbox (‘[ ]’/‘[X]’). ‘editable-list’ Create an editable list. The user can insert or delete items in the list. Each list item is itself a widget. Now, of what possible use can support for widgets be in a text editor? I’m glad you asked. The answer is that widgets are useful for implementing forms. A “form” in Emacs is a buffer where the user is supposed to fill out a number of fields, each of which has a specific meaning. The user is not supposed to change or delete any of the text between the fields. Examples of forms in Emacs are the ‘forms’ package (of course), the customize buffers, the mail and news compose modes, and the HTML form support in the ‘w3’ browser. The advantages for a programmer of using the ‘widget’ package to implement forms are: 1. More complex fields than just editable text are supported. 2. You can give the users immediate feedback if they enter invalid data in a text field, and sometimes prevent entering invalid data. 3. You can have fixed sized fields, thus allowing multiple fields to be lined up in columns. 4. It is simple to query or set the value of a field. 5. Editing happens in the buffer, not in the mini-buffer. 6. Packages using the library get a uniform look, making them easier for the user to learn. 7. 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. 2 User Interface **************** 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 ‘foo field’, meaning the field tagged with ‘Foo’. Here is an example form: Here is some documentation. Name: My Name *Choose*: This option Address: Some Place In some City Some country. See also _other work_ for more information. Numbers: count to three below [INS] [DEL] One [INS] [DEL] Eh, two? [INS] [DEL] Five! [INS] Select multiple: [X] This [ ] That [X] Thus Select one: (*) One ( ) Another One. ( ) A Final One. [Apply Form] [Reset Form] The top level widgets in this example are tagged ‘Name’, ‘Choose’, ‘Address’, ‘_other work_’, ‘Numbers’, ‘Select multiple’, ‘Select one’, ‘[Apply Form]’, and ‘[Reset Form]’. There are basically two things the user can do within a form, namely editing the editable text fields and activating the buttons. 2.1 Editable Text Fields ======================== In the example, the value for the ‘Name’ is most likely displayed in an editable text field, and so are values for each of the members of the ‘Numbers’ list. All the normal Emacs editing operations are available for editing these fields. The only restriction is that each change you make must be contained within a single editable text field. For example, capitalizing all text from the middle of one field to the middle of another field is prohibited. Editable text fields are created by the ‘editable-field’ widget. *Warning:* In an ‘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 ‘editable-field’ widget itself, or insert it with ‘widget-insert’. The ‘:format’ keyword is useful for generating the necessary text; for instance, if you give it a value of ‘"Name: %v "’, the ‘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 ‘:size’ keyword, the field will extend to the end of the line, and the terminating newline will provide separation after. *Warning:* In an ‘editable-field’ widget, the ‘%v’ escape must be preceded by some other text in the ‘:format’ string (if specified). The editing text fields are highlighted with the ‘widget-field-face’ face, making them easy to find. -- Face: widget-field-face Face used for other editing fields. 2.2 Buttons =========== Some portions of the buffer have an associated “action”, which can be “invoked” by a standard key or mouse command. These portions are called “buttons”. The default commands for activating a button are: ‘’ -- Command: widget-button-press POS &optional EVENT Invoke the button at POS, defaulting to point. If point is not located on a button, invoke the binding in ‘widget-global-map’ (by default the global map). ‘mouse-2’ -- Command: widget-button-click 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 ‘widget-global-map’ (by default the global map). There are several different kind of buttons, all of which are present in the example: _The Option Field Tags_ When you invoke one of these buttons, you will be asked to choose between a number of different options. This is how you edit an option field. Option fields are created by the ‘menu-choice’ widget. In the example, ‘Choose’ is an option field tag. _The ‘[INS]’ and ‘[DEL]’ buttons_ Activating these will insert or delete elements from an editable list. The list is created by the ‘editable-list’ widget. _Embedded Buttons_ The ‘_other work_’ is an example of an embedded 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 ‘link’ widget. _The ‘[ ]’ and ‘[X]’ buttons_ Activating one of these will convert it to the other. This is useful for implementing multiple-choice fields. You can create them with the ‘checkbox’ widget. _The ‘( )’ and ‘(*)’ buttons_ Only one radio button in a ‘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. _The ‘[Apply Form]’ and ‘[Reset Form]’ buttons_ These are explicit buttons made with the ‘push-button’ widget. The main difference from the ‘link’ widget is that the buttons will be displayed as GUI buttons when possible. To make them easier to locate, buttons are emphasized in the buffer. -- Face: widget-button-face Face used for buttons. -- User Option: widget-mouse-face Face used for highlighting a button when the mouse pointer moves across it. 2.3 Navigation ============== You can use all the normal Emacs commands to move around in a form buffer, plus you will have these additional commands: ‘’ -- Command: widget-forward &optional count Move point COUNT buttons or editing fields forward. ‘M-’ ‘S-’ -- Command: widget-backward &optional count Move point COUNT buttons or editing fields backward. 3 Programming Example ********************* Here is the code to implement the user interface example (*note User Interface::). (require 'widget) (eval-when-compile (require 'wid-edit)) (defvar widget-example-repeat) (defun widget-example () "Create the widgets from the Widget manual." (interactive) (switch-to-buffer "*Widget Example*") (kill-all-local-variables) (make-local-variable 'widget-example-repeat) (let ((inhibit-read-only t)) (erase-buffer)) (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" :value "This" :help-echo "Choose me, please!" :notify (lambda (widget &rest ignore) (message "%s is a good choice!" (widget-value widget))) '(item :tag "This option" :value "This") '(choice-item "That option") '(editable-field :menu-tag "No option" "Thus option")) (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 '("En" "To" "Tre")) (widget-setup)) "other work") (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" :notify (lambda (widget &rest ignore) (let ((old (widget-get widget ':example-length)) (new (length (widget-value widget)))) (unless (eq old new) (widget-put widget ':example-length new) (message "You can count to %d." new)))) :value '("One" "Eh, two?" "Five!") '(editable-field :value "three"))) (widget-insert "\n\nSelect multiple:\n\n") (widget-create 'checkbox t) (widget-insert " This\n") (widget-create 'checkbox nil) (widget-insert " That\n") (widget-create 'checkbox :notify (lambda (&rest ignore) (message "Tickle")) t) (widget-insert " Thus\n\nSelect one:\n\n") (widget-create 'radio-button-choice :value "One" :notify (lambda (widget &rest ignore) (message "You selected %s" (widget-value widget))) '(item "One") '(item "Another One.") '(item "A Final One.")) (widget-insert "\n") (widget-create 'push-button :notify (lambda (&rest ignore) (if (= (length (widget-value widget-example-repeat)) 3) (message "Congratulation!") (error "Three was the count!"))) "Apply Form") (widget-insert " ") (widget-create 'push-button :notify (lambda (&rest ignore) (widget-example)) "Reset Form") (widget-insert "\n") (use-local-map widget-keymap) (widget-setup)) 4 Setting Up the Buffer *********************** Widgets are created with ‘widget-create’, which returns a “widget” object. This object can be queried and manipulated by other widget functions, until it is deleted with ‘widget-delete’. After the widgets have been created, ‘widget-setup’ must be called to enable them. -- Function: widget-create type [ keyword argument ]... Create and return a widget of type TYPE. The syntax for the TYPE argument is described in *note Basic Types::. The keyword arguments can be used to overwrite the keyword arguments that are part of TYPE. -- Function: widget-delete widget Delete WIDGET and remove it from the buffer. -- Function: 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 ‘widget-insert’. -- Function: widget-insert Insert the arguments, either strings or characters, at point. The inserted text will be read-only. There is a standard widget keymap which you might find useful. -- Const: widget-keymap and ‘C-’ are bound to ‘widget-forward’ and ‘widget-backward’, respectively. and ‘mouse-2’ are bound to ‘widget-button-press’ and ‘widget-button-click’. -- Variable: widget-global-map Keymap used by ‘widget-button-press’ and ‘widget-button-click’ when not on a button. By default this is ‘global-map’. 5 Basic Types ************* This is the general syntax of a type specification: NAME ::= (NAME [KEYWORD ARGUMENT]... ARGS) | NAME Where, NAME is a widget name, KEYWORD is the name of a property, ARGUMENT is the value of the property, and ARGS are interpreted in a widget specific way. The following keyword arguments apply to all widgets: ‘:value’ The initial value for widgets of this type. Typically, a widget represents its value in two formats: external and internal. The external format is the value as the rest of Emacs sees it, and the internal format is a representation that the widget defines and uses in a widget specific way. Both formats might be the same for certain widgets and might differ for others, and there is no guarantee about which format the value stored in the ‘:value’ property has. However, when creating a widget or defining a new one (*note Defining New Widgets::), the ‘:value’ should be in the external format. ‘:format’ This string will be inserted in the buffer when you create a widget. The following ‘%’ escapes are available: ‘%[’ ‘%]’ The text inside will be marked as a button. By default, the text will be shown in ‘widget-button-face’, and surrounded by brackets. -- User Option: widget-button-prefix String to prefix buttons. -- User Option: widget-button-suffix String to suffix buttons. ‘%{’ ‘%}’ The text inside will be displayed with the face specified by ‘:sample-face’. ‘%v’ This will be replaced with the buffer representation of the widget’s value. What this is depends on the widget type. *Warning:* In an ‘editable-field’ widget, the ‘%v’ escape must be preceded by some other text in the format string (if specified). ‘%d’ Insert the string specified by ‘:doc’ here. ‘%h’ Like ‘%d’, with the following modifications: If the documentation string is more than one line, it will add a button which will toggle between showing only the first line, and showing the full text. Furthermore, if there is no ‘:doc’ property in the widget, it will instead examine the ‘:documentation-property’ property. If it is a lambda expression, it will be called with the widget’s value as an argument, and the result will be used as the documentation text. ‘%t’ Insert the string specified by ‘:tag’ here, or the ‘princ’ representation of the value if there is no tag. ‘%%’ Insert a literal ‘%’. ‘:button-face’ Face used to highlight text inside %[ %] in the format. ‘:button-prefix’ ‘:button-suffix’ Text around %[ %] in the format. These can be _nil_ No text is inserted. _a string_ The string is inserted literally. _a symbol_ The value of the symbol is expanded according to this table. ‘:doc’ The string inserted by the ‘%d’ escape in the format string. ‘:tag’ The string inserted by the ‘%t’ escape in the format string. ‘:tag-glyph’ Name of image to use instead of the string specified by ‘:tag’ on Emacsen that supports it. ‘:help-echo’ Specifies how to display a message whenever you move to the widget with either ‘widget-forward’ or ‘widget-backward’ or move the mouse over it (using the standard ‘help-echo’ mechanism). The argument 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. ‘:follow-link’ Specifies how to interpret a click on the widget. *Note Defining Clickable Text: (elisp)Clickable Text. ‘:indent’ An integer indicating the absolute number of spaces to indent children of this widget. ‘:offset’ An integer indicating how many extra spaces to add to the widget’s grandchildren compared to this widget. ‘:extra-offset’ An integer indicating how many extra spaces to add to the widget’s children compared to this widget. ‘:notify’ A function called each time the widget or a nested widget is changed. 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. ‘:menu-tag’ Tag used in the menu when the widget is used as an option in a ‘menu-choice’ widget. ‘:menu-tag-get’ Function used for finding the tag when the widget is used as an option in a ‘menu-choice’ widget. By default, the tag used will be either the ‘:menu-tag’ or ‘:tag’ property if present, or the ‘princ’ representation of the ‘:value’ property if not. ‘:match’ Should be a function called with two arguments, the widget and an external value, and should return non-‘nil’ if the widget can represent the specified value. ‘:validate’ A function which takes a widget as an argument, and returns ‘nil’ if the widget’s current value is valid for the widget. Otherwise it should return the widget containing the invalid data, and set that widget’s ‘:error’ property to a string explaining the error. The following predefined function can be used: -- Function: widget-children-validate widget All the ‘:children’ of WIDGET must be valid. ‘:tab-order’ Specify the order in which widgets are traversed with ‘widget-forward’ or ‘widget-backward’. This is only partially implemented. a. Widgets with tabbing order ‘-1’ are ignored. b. (Unimplemented) When on a widget with tabbing order N, go to the next widget in the buffer with tabbing order N+1 or ‘nil’, whichever comes first. c. When on a widget with no tabbing order specified, go to the next widget in the buffer with a positive tabbing order, or ‘nil’ ‘:parent’ The parent of a nested widget (e.g., a ‘menu-choice’ item or an element of a ‘editable-list’ widget). ‘:sibling-args’ This keyword is only used for members of a ‘radio-button-choice’ or ‘checklist’. The value should be a list of extra keyword arguments, which will be used when creating the ‘radio-button’ or ‘checkbox’ associated with this item. -- User Option: widget-image-directory Directory where Widget should look for images. Widget will look here for a file with the same name as specified for the image, with either a ‘.xpm’ (if supported) or ‘.xbm’ extension. -- User Option: widget-image-enable If non-‘nil’, allow images to appear on displays where they are supported. 5.1 The ‘link’ Widget ===================== Syntax: TYPE ::= (link [KEYWORD ARGUMENT]... [ VALUE ]) The VALUE, if present, is used to initialize the ‘:value’ property. The value should be a string, which will be inserted in the buffer. By default the link will be shown in brackets. -- User Option: widget-link-prefix String to prefix links. -- User Option: widget-link-suffix String to suffix links. 5.2 The ‘url-link’ Widget ========================= Syntax: TYPE ::= (url-link [KEYWORD ARGUMENT]... URL) When this link is invoked, the WWW browser specified by ‘browse-url-browser-function’ will be called with URL. 5.3 The ‘info-link’ Widget ========================== Syntax: TYPE ::= (info-link [KEYWORD ARGUMENT]... ADDRESS) When this link is invoked, the built-in Info reader is started on ADDRESS. 5.4 The ‘push-button’ Widget ============================ Syntax: TYPE ::= (push-button [KEYWORD ARGUMENT]... [ VALUE ]) The VALUE, if present, is used to initialize the ‘:value’ property. The value should be a string, which will be inserted in the buffer. By default the tag will be shown in brackets. -- User Option: widget-push-button-prefix String to prefix push buttons. -- User Option: widget-push-button-suffix String to suffix push buttons. 5.5 The ‘editable-field’ Widget =============================== Syntax: TYPE ::= (editable-field [KEYWORD ARGUMENT]... [ VALUE ]) The VALUE, if present, is used to initialize the ‘:value’ 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: ‘:size’ The width of the editable field. By default the field will reach to the end of the line. ‘:value-face’ Face used for highlighting the editable field. Default is ‘widget-field-face’, see *note User Interface::. ‘:secret’ Character used to display the value. You can set this to, e.g., ‘?*’ if the field contains a password or other secret information. By default, this is ‘nil’, and the value is not secret. ‘:valid-regexp’ By default the ‘:validate’ function will match the content of the field with the value of this attribute. The default value is ‘""’ which matches everything. ‘:keymap’ Keymap used in the editable field. The default value is ‘widget-field-keymap’, which allows you to use all the normal editing commands, even if the buffer’s major mode suppresses some of them. Pressing invokes the function specified by ‘:action’. 5.6 The ‘text’ Widget ===================== This is just like ‘editable-field’, but intended for multiline text fields. The default ‘:keymap’ is ‘widget-text-keymap’, which does not rebind the key. 5.7 The ‘menu-choice’ Widget ============================ Syntax: TYPE ::= (menu-choice [KEYWORD ARGUMENT]... TYPE ... ) The TYPE argument represents each possible choice. The widget’s value will be that of the chosen TYPE argument. This widget will match any value matching at least one of the specified TYPE arguments. ‘:void’ Widget type used as a fallback when the value does not match any of the specified TYPE arguments. ‘:case-fold’ Set this to ‘nil’ if you don’t want to ignore case when prompting for a choice through the minibuffer. ‘:children’ A list whose CAR is the widget representing the currently chosen type in the buffer. ‘:choice’ The current chosen type. ‘:args’ The list of types. 5.8 The ‘radio-button-choice’ Widget ==================================== Syntax: TYPE ::= (radio-button-choice [KEYWORD ARGUMENT]... TYPE ... ) The component types specify the choices, with one radio button for each. The widget’s value will be that of the chosen TYPE argument. This widget matches any value that matches at least one of the specified TYPE arguments. The following extra properties are recognized. ‘:entry-format’ This string will be inserted for each entry in the list. The following ‘%’ escapes are available: ‘%v’ Replace with the buffer representation of the TYPE widget. ‘%b’ Replace with the radio button. ‘%%’ Insert a literal ‘%’. ‘:button-args’ A list of keywords to pass to the radio buttons. Useful for setting, e.g., the ‘:help-echo’ for each button. ‘:buttons’ The widgets representing the radio buttons. ‘:children’ The widgets representing each type. ‘:choice’ The current chosen type ‘:args’ The list of types. You can add extra radio button items to a ‘radio-button-choice’ widget after it has been created with the function ‘widget-radio-add-item’. -- Function: widget-radio-add-item widget type Add to ‘radio-button-choice’ widget WIDGET a new radio button item of type TYPE. Please note that such items added after the ‘radio-button-choice’ widget has been created will *not* be properly destructed when you call ‘widget-delete’. 5.9 The ‘item’ Widget ===================== Syntax: ITEM ::= (item [KEYWORD ARGUMENT]... VALUE) The VALUE, if present, is used to initialize the ‘:value’ property. The value should be a string, which will be inserted in the buffer. This widget will only match the specified value. 5.10 The ‘choice-item’ Widget ============================= Syntax: ITEM ::= (choice-item [KEYWORD ARGUMENT]... VALUE) The VALUE, if present, is used to initialize the ‘:value’ property. The value should be a string, which will be inserted in the buffer as a button. Activating the button of a ‘choice-item’ is equivalent to activating the parent widget. This widget will only match the specified value. 5.11 The ‘toggle’ Widget ======================== Syntax: TYPE ::= (toggle [KEYWORD ARGUMENT]...) The widget has two possible states, ‘on’ and ‘off’, which correspond to a ‘t’ or ‘nil’ value, respectively. The following extra properties are recognized: ‘:on’ A string representing the ‘on’ state. By default the string ‘on’. ‘:off’ A string representing the ‘off’ state. By default the string ‘off’. ‘:on-glyph’ Name of a glyph to be used instead of the ‘:on’ text string, on emacsen that supports this. ‘:off-glyph’ Name of a glyph to be used instead of the ‘:off’ text string, on emacsen that supports this. 5.12 The ‘checkbox’ Widget ========================== This widget has two possible states, ‘selected’ and ‘unselected’, which corresponds to a ‘t’ or ‘nil’ value. Syntax: TYPE ::= (checkbox [KEYWORD ARGUMENT]...) 5.13 The ‘checklist’ Widget =========================== Syntax: TYPE ::= (checklist [KEYWORD ARGUMENT]... TYPE ... ) The TYPE arguments represent each checklist item. The widget’s value will be a list containing the values of all checked TYPE arguments. The checklist widget will match a list whose elements all match at least one of the specified TYPE arguments. The following extra properties are recognized: ‘:entry-format’ This string will be inserted for each entry in the list. The following ‘%’ escapes are available: ‘%v’ Replaced with the buffer representation of the TYPE widget. ‘%b’ Replace with the checkbox. ‘%%’ Insert a literal ‘%’. ‘:greedy’ Usually a checklist will only match if the items are in the exact sequence given in the specification. By setting ‘: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. ‘:button-args’ A list of keywords to pass to the checkboxes. Useful for setting, e.g., the ‘:help-echo’ for each checkbox. ‘:buttons’ The widgets representing the checkboxes. ‘:children’ The widgets representing each type. ‘:args’ The list of types. 5.14 The ‘editable-list’ Widget =============================== Syntax: TYPE ::= (editable-list [KEYWORD ARGUMENT]... TYPE) The value is a list, where each member represents one widget of type TYPE. The following extra properties are recognized: ‘:entry-format’ This string will be inserted for each entry in the list. The following ‘%’ escapes are available: ‘%v’ This will be replaced with the buffer representation of the TYPE widget. ‘%i’ Insert the [INS] button. ‘%d’ Insert the [DEL] button. ‘%%’ Insert a literal ‘%’. ‘:insert-button-args’ A list of keyword arguments to pass to the insert buttons. ‘:delete-button-args’ A list of keyword arguments to pass to the delete buttons. ‘:append-button-args’ A list of keyword arguments to pass to the trailing insert button. ‘:buttons’ The widgets representing the insert and delete buttons. ‘:children’ The widgets representing the elements of the list. ‘:args’ List whose CAR is the type of the list elements. 5.15 The ‘group’ Widget ======================= This widget simply group other widgets together. Syntax: TYPE ::= (group [KEYWORD ARGUMENT]... TYPE...) The value is a list, with one member for each TYPE. 6 Sexp Types ************ A number of widgets for editing “s-expressions” (Lisp types), sexp for short, are also available. These basically fall in several categories described in this section. 6.1 The Constant Widgets ======================== The ‘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 ‘const’ widget is: TYPE ::= (const [KEYWORD ARGUMENT]... [ VALUE ]) The VALUE, if present, is used to initialize the ‘:value’ property and can be any s-expression. -- Widget: const This will display any valid s-expression in an immutable part of the buffer. There are two variations of the ‘const’ widget, namely ‘variable-item’ and ‘function-item’. These should contain a symbol with a variable or function binding. The major difference from the ‘const’ widget is that they will allow the user to see the variable or function documentation for the symbol. -- Widget: variable-item An immutable symbol that is bound as a variable. -- Widget: function-item An immutable symbol that is bound as a function. 6.2 Generic Sexp Widget ======================= The ‘sexp’ widget can contain any Lisp expression, and allows the user to edit it inline in the buffer. The syntax for the ‘sexp’ widget is: TYPE ::= (sexp [KEYWORD ARGUMENT]... [ VALUE ]) -- Widget: sexp This will allow you to edit any valid s-expression in an editable buffer field. The ‘sexp’ widget takes the same keyword arguments as the ‘editable-field’ widget. *Note editable-field::. 6.3 Atomic Sexp Widgets ======================= The atoms are s-expressions that do not consist of other s-expressions. For example, a string, a file name, or a symbol are atoms, while a list is a composite type. You can edit the value of an atom with the following widgets. The syntax for all the atoms are: TYPE ::= (CONSTRUCT [KEYWORD ARGUMENT]... [ VALUE ]) The VALUE, if present, is used to initialize the ‘:value’ property and must be an expression of the same type as the widget. That is, the string widget can only be initialized with a string. All the atom widgets take the same keyword arguments as the ‘editable-field’ widget. *Note editable-field::. -- Widget: string Allows you to edit a string in an editable field. -- Widget: regexp Allows you to edit a regular expression in an editable field. -- Widget: character Allows you to enter a character in an editable field. -- Widget: file Allows you to edit a file name in an editable field. Keywords: ‘:must-match’ If this is set to non-‘nil’, only existing file names will be allowed in the minibuffer. -- Widget: directory Allows you to edit a directory name in an editable field. Similar to the ‘file’ widget. -- Widget: symbol Allows you to edit a Lisp symbol in an editable field. -- Widget: function Allows you to edit a lambda expression, or a function name with completion. -- Widget: variable Allows you to edit a variable name, with completion. -- Widget: integer Allows you to edit an integer in an editable field. -- Widget: number Allows you to edit a number in an editable field. -- 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. 6.4 Composite Sexp Widgets ========================== The syntax for the composite widget construct is: TYPE ::= (CONSTRUCT [KEYWORD ARGUMENT]... COMPONENT...) where each COMPONENT must be a widget type. Each component widget will be displayed in the buffer, and will be editable by the user. -- Widget: cons The value of a ‘cons’ widget must be a cons-cell whose CAR and CDR have two specified types. It uses this syntax: TYPE ::= (cons [KEYWORD ARGUMENT]... CAR-TYPE CDR-TYPE) -- Widget: choice The value matched by a ‘choice’ widget must have one of a fixed set of types. The widget’s syntax is as follows: TYPE ::= (choice [KEYWORD ARGUMENT]... TYPE ... ) The value of a ‘choice’ widget can be anything that matches any of the TYPES. -- Widget: list The value of a ‘list’ widget must be a list whose element types match the specified component types: TYPE ::= (list [KEYWORD ARGUMENT]... COMPONENT-TYPE...) Thus, ‘(list string number)’ matches lists of two elements, the first being a string and the second being a number. -- Widget: vector The ‘vector’ widget is like the ‘list’ widget but matches vectors instead of lists. Thus, ‘(vector string number)’ matches vectors of two elements, the first being a string and the second being a number. The above suffice for specifying fixed size lists and vectors. To get variable length lists and vectors, you can use a ‘choice’, ‘set’, or ‘repeat’ widget together with the ‘:inline’ keyword. If any component of a composite widget has the ‘: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 ‘t’ or two strings (file names), you can use the following widget specification: (list file (choice (const t) (list :inline t :value ("foo" "bar") string string))) The value of a widget of this type will either have the form ‘(file t)’ or ‘(file STRING STRING)’. This concept of ‘: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. -- Widget: set 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: TYPE ::= (set [KEYWORD ARGUMENT]... PERMITTED-ELEMENT ... ) Use ‘const’ to specify each permitted element, like this: ‘(set (const a) (const b))’. -- Widget: repeat Specifies a list of any number of elements that fit a certain type. TYPE ::= (repeat [KEYWORD ARGUMENT]... TYPE) 7 Properties ************ You can examine or set the value of a widget by using the widget object that was returned by ‘widget-create’. -- Function: widget-value widget Return the current value contained in WIDGET. It is an error to call this function on an uninitialized widget. -- Function: widget-value-set widget value Set the value contained in WIDGET to VALUE. It is an error to call this function with an invalid VALUE. *Important:* You _must_ call ‘widget-setup’ after modifying the value of a widget before the user is allowed to edit the widget again. It is enough to call ‘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. If your application needs to associate some information with the widget objects, for example a reference to the item being edited, it can be done with ‘widget-put’ and ‘widget-get’. The property names must begin with a ‘:’. -- Function: widget-put widget property value In WIDGET set PROPERTY to VALUE. PROPERTY should be a symbol, while VALUE can be anything. -- Function: widget-get widget property In WIDGET return the value for PROPERTY. PROPERTY should be a symbol, the value is what was last set by ‘widget-put’ for PROPERTY. -- Function: widget-member widget property Non-‘nil’ if WIDGET has a value (even ‘nil’) for property PROPERTY. -- Function: widget-apply widget property &rest args Apply the value of PROPERTY to WIDGET, passing ARGS as additional arguments to the function. Return the result of that function call. 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. -- Function: widget-type widget Return the name of WIDGET, a symbol. Widgets can be in two states: active, which means they are modifiable by the user, or inactive, which means they cannot be modified by the user. You can query or set the state with the following code: ;; Examine if WIDGET is active or not. (if (widget-apply WIDGET :active) (message "Widget is active.") (message "Widget is inactive.") ;; Make WIDGET inactive. (widget-apply WIDGET :deactivate) ;; Make WIDGET active. (widget-apply WIDGET :activate) A widget is inactive if it, or any of its ancestors (found by following the ‘:parent’ link), have been deactivated. To make sure a widget is really active, you must therefore activate both it and all its ancestors. (while widget (widget-apply widget :activate) (setq widget (widget-get widget :parent))) You can check if a widget has been made inactive by examining the value of the ‘:inactive’ keyword. If this is non-‘nil’, the widget itself has been deactivated. This is different from using the ‘:active’ keyword, in that the latter tells you if the widget *or* any of its ancestors have been deactivated. Do not attempt to set the ‘:inactive’ keyword directly. Use the ‘:activate’ ‘:deactivate’ keywords instead. 8 Defining New Widgets ********************** You can define specialized widgets with ‘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. -- Function: define-widget name class doc &rest args Define a new widget type named NAME from ‘class’. NAME and class should both be symbols, ‘class’ should be one of the existing widget types. The third argument DOC is a documentation string for the widget. After the new widget has been defined, the following two calls will create identical widgets: • (widget-create NAME) • (apply widget-create CLASS ARGS) Using ‘define-widget’ just stores the definition of the widget type in the ‘widget-type’ property of NAME, which is what ‘widget-create’ uses. If you only want to specify defaults for keywords with no complex conversions, you can use ‘identity’ as your conversion function. The following additional keyword arguments are useful when defining new widgets: ‘: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. The following predefined functions can be used here: -- Function: widget-types-convert-widget widget Convert ‘:args’ as widget types in WIDGET. -- Function: widget-value-convert-widget widget Initialize ‘:value’ from ‘:args’ in WIDGET. ‘:copy’ Function to deep copy a widget type. It takes a shallow copy of the widget type as an argument (made by ‘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: -- Function: widget-types-copy widget Copy ‘:args’ as widget types in WIDGET. ‘:value-to-internal’ Function to convert the value to the internal format. The function takes two arguments, a widget and an external value, and returns the internal value. The function is called on the present ‘:value’ when the widget is created, and on any value set later with ‘widget-value-set’. ‘:value-to-external’ Function to convert the value to the external format. The function takes two arguments, a widget and an internal value, and returns the external value. ‘:create’ Function to create a widget from scratch. The function takes one argument, a widget type, and creates a widget of that type, inserts it in the buffer, and returns a widget object. ‘:delete’ 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: -- Function: widget-default-delete widget Remove WIDGET from the buffer. Delete all ‘:children’ and ‘:buttons’ in WIDGET. In most cases you should not change this value, but instead use ‘:value-delete’ to make any additional cleanup. ‘:value-create’ Function to expand the ‘%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 ‘:children’ or ‘:buttons’ to make sure they are automatically deleted. ‘: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 these are not listed in ‘:children’ or ‘:buttons’. ‘:value-get’ Function to extract the value of a widget, as it is displayed in the buffer. The following predefined function can be used here: -- Function: widget-value-value-get widget Return the ‘:value’ property of WIDGET. ‘:format-handler’ Function to handle unknown ‘%’ escapes in the format string. It will be called with the widget and the character that follows the ‘%’ as arguments. You can set this to allow your widget to handle non-standard escapes. You should end up calling ‘widget-default-format-handler’ to handle unknown escape sequences, which will handle the ‘%h’ and any future escape sequences, as well as give an error for unknown escapes. ‘:action’ Function to handle user initiated events. By default, ‘:notify’ the parent. The following predefined function can be used here: -- Function: widget-parent-action widget &optional event Tell ‘:parent’ of WIDGET to handle the ‘:action’. Optional EVENT is the event that triggered the action. ‘:prompt-value’ Function to prompt for a value in the minibuffer. The function should take four arguments, WIDGET, PROMPT, VALUE, and UNBOUND and should return a value for widget entered by the user. PROMPT is the prompt to use. VALUE is the default value to use, unless UNBOUND is non-‘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. If you want to define a new widget from scratch, use the ‘default’ widget as its base. -- 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. 9 Widget Browser **************** There is a separate package to browse widgets. This is intended to help programmers who want to examine the content of a widget. The browser shows the value of each keyword, but uses links for certain keywords such as ‘:parent’, which avoids printing cyclic structures. -- Command: widget-browse WIDGET Create a widget browser for WIDGET. When called interactively, prompt for WIDGET. -- Command: widget-browse-other-window WIDGET Create a widget browser for WIDGET and show it in another window. When called interactively, prompt for WIDGET. -- Command: widget-browse-at POS Create a widget browser for the widget at POS. When called interactively, use the position of point. 10 Widget Minor Mode ******************** 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. -- Command: widget-minor-mode Toggle minor mode for traversing widgets. With arg, turn widget mode on if and only if arg is positive. -- Variable: widget-minor-mode-keymap Keymap used in ‘widget-minor-mode’. 11 Utilities ************ -- Function: widget-prompt-value widget prompt [ value unbound ] Prompt for a value matching WIDGET, using PROMPT. The current value is assumed to be VALUE, unless UNBOUND is non-‘nil’. -- Function: widget-get-sibling widget Get the item which WIDGET is assumed to toggle. This is only meaningful for radio buttons or checkboxes in a list. -- Function: widget-choose title items &optional event Prompt the user to choose an item from a list of options. TITLE is the name of the list of options. ITEMS should be a menu, with its items in the simple format or in the extended format. *Note Defining Menus: (elisp)Defining Menus. Independently of the format, you don’t have to provide a title for the menu, just pass the desired title in TITLE. The optional EVENT is an input event. If EVENT is a mouse event and the number of elements in ITEMS is less than the user option ‘widget-menu-max-size’, then ‘widget-choose’ uses a popup menu to prompt the user. Otherwise, ‘widget-choose’ uses the minibuffer. When ITEMS is a keymap menu, the returned value is the symbol in the key vector, as in the argument of ‘define-key’ (*note (elisp)Changing Key Bindings::). When ITEMS is a list whose selectable items are of the form (NAME . VALUE) (i.e., the simplified format), then the return value is the VALUE of the chosen element. 12 Wishlist *********** • It should be possible to add or remove items from a list with ‘C-k’ and ‘C-o’ (suggested by RMS). • The ‘[INS]’ and ‘[DEL]’ buttons should be replaced by a single dash (‘-’). The dash should be a button that, when invoked, asks whether you want to add or delete an item (RMS wanted to git rid of the ugly buttons, the dash is my idea). • The ‘menu-choice’ tag should be prettier, something like the abbreviated menus in Open Look. • Finish ‘:tab-order’. • Make indentation work with glyphs and proportional fonts. • Add commands to show overview of object and class hierarchies to the browser. • Find a way to disable mouse highlight for inactive widgets. • Find a way to make glyphs look inactive. • Add ‘property-list’ widget. • Add ‘association-list’ widget. • Add ‘key-binding’ widget. • Add ‘widget’ widget for editing widget specifications. • Find clean way to implement variable length list. See ‘TeX-printer-list’ for an explanation. • ‘C-h’ in ‘widget-prompt-value’ should give type specific help. • Add a ‘mailto’ widget. Appendix A GNU Free Documentation License ***************************************** Version 1.3, 3 November 2008 Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. 0. PREAMBLE The purpose of this License is to make a manual, textbook, or other functional and useful document “free” in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others. This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software. We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference. 1. APPLICABILITY AND DEFINITIONS This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. 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The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing. ADDENDUM: How to use this License for your documents ==================================================== To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page: Copyright (C) YEAR YOUR NAME. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''. If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with...Texts.” line with this: with the Invariant Sections being LIST THEIR TITLES, with the Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST. If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation. If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software. Index ***** This is an alphabetical listing of all concepts, functions, commands, variables, and widgets described in this manual. * Menu: * action keyword: Defining New Widgets. (line 1333) * activate a widget: Widget Properties. (line 1181) * active widget: Widget Properties. (line 1181) * append-button-args keyword: editable-list. (line 919) * args keyword: menu-choice. (line 731) * args keyword <1>: radio-button-choice. (line 771) * args keyword <2>: checklist. (line 885) * args keyword <3>: editable-list. (line 928) * atomic sexp widget: atoms. (line 999) * basic widgets: Introduction. (line 63) * boolean: atoms. (line 1052) * browse-url-browser-function, and url-link widget: url-link. (line 629) * button widgets: User Interface. (line 200) * button-args keyword: radio-button-choice. (line 758) * button-args keyword <1>: checklist. (line 875) * button-face keyword: Basic Types. (line 486) * button-prefix keyword: Basic Types. (line 489) * button-suffix keyword: Basic Types. (line 489) * buttons keyword: radio-button-choice. (line 762) * buttons keyword <1>: checklist. (line 879) * buttons keyword <2>: editable-list. (line 922) * case-fold keyword: menu-choice. (line 720) * character: atoms. (line 1021) * checkbox widget: checkbox. (line 837) * checklist widget: checklist. (line 847) * children keyword: menu-choice. (line 724) * children keyword <1>: radio-button-choice. (line 765) * children keyword <2>: checklist. (line 882) * children keyword <3>: editable-list. (line 925) * choice: composite. (line 1072) * choice keyword: menu-choice. (line 728) * choice keyword <1>: radio-button-choice. (line 768) * choice-item widget: choice-item. (line 800) * composite sexp widgets: composite. (line 1059) * cons: composite. (line 1066) * const: constants. (line 963) * constant widgets: constants. (line 952) * convert-widget keyword: Defining New Widgets. (line 1243) * copy keyword: Defining New Widgets. (line 1258) * create keyword: Defining New Widgets. (line 1281) * deactivate a widget: Widget Properties. (line 1181) * default: Defining New Widgets. (line 1355) * define-widget: Defining New Widgets. (line 1219) * defining new widgets: Defining New Widgets. (line 1215) * delete keyword: Defining New Widgets. (line 1286) * delete-button-args keyword: editable-list. (line 916) * directory: atoms. (line 1032) * doc keyword: Basic Types. (line 503) * editable-field widget: editable-field. (line 663) * editable-list widget: editable-list. (line 891) * embedded buttons: User Interface. (line 227) * entry-format keyword: radio-button-choice. (line 748) * entry-format keyword <1>: checklist. (line 858) * entry-format keyword <2>: editable-list. (line 900) * example of using widgets: Programming Example. (line 273) * external format: Basic Types. (line 422) * extra-offset keyword: Basic Types. (line 533) * file: atoms. (line 1024) * follow-link keyword: Basic Types. (line 521) * format keyword: Basic Types. (line 435) * format-handler keyword: Defining New Widgets. (line 1323) * function: atoms. (line 1039) * function-item: constants. (line 976) * generic sexp widget: generic. (line 982) * greedy keyword: checklist. (line 868) * group widget: group. (line 934) * help-echo keyword: Basic Types. (line 513) * inactive widget: Widget Properties. (line 1181) * indent keyword: Basic Types. (line 525) * info-link widget: info-link. (line 635) * insert-button-args keyword: editable-list. (line 913) * integer: atoms. (line 1046) * internal format: Basic Types. (line 422) * item widget: item. (line 789) * keymap keyword: editable-field. (line 691) * keyword arguments: Basic Types. (line 420) * link widget: link. (line 607) * list: composite. (line 1081) * match keyword: Basic Types. (line 554) * menu-choice widget: menu-choice. (line 708) * menu-tag keyword: Basic Types. (line 544) * menu-tag-get keyword: Basic Types. (line 548) * mouse-2 (on button widgets): User Interface. (line 210) * must-match keyword: atoms. (line 1028) * new widgets: Defining New Widgets. (line 1215) * notify keyword: Basic Types. (line 537) * number: atoms. (line 1049) * off-glyph keyword: toggle. (line 829) * offset keyword: Basic Types. (line 529) * on-glyph keyword: toggle. (line 826) * option field tag: User Interface. (line 220) * parent keyword: Basic Types. (line 585) * prompt-value keyword: Defining New Widgets. (line 1343) * properties of widgets: Widget Properties. (line 1136) * push-button widget: push-button. (line 645) * radio-button-choice widget: radio-button-choice. (line 737) * regexp: atoms. (line 1018) * repeat: composite. (line 1128) * secret keyword: editable-field. (line 681) * set: composite. (line 1118) * sexp: generic. (line 989) * sexp types: Sexp Types. (line 945) * sibling-args keyword: Basic Types. (line 589) * size keyword: editable-field. (line 673) * string: atoms. (line 1015) * symbol: atoms. (line 1036) * tab-order keyword: Basic Types. (line 570) * tag keyword: Basic Types. (line 506) * tag-glyph keyword: Basic Types. (line 509) * text widget: text. (line 701) * todo: Widget Wishlist. (line 1429) * toggle widget: toggle. (line 813) * url-link widget: url-link. (line 625) * utility functions for widgets: Utilities. (line 1398) * valid-regexp keyword: editable-field. (line 686) * validate keyword: Basic Types. (line 559) * value keyword: Basic Types. (line 422) * value-create keyword: Defining New Widgets. (line 1299) * value-delete keyword: Defining New Widgets. (line 1307) * value-face keyword: editable-field. (line 677) * value-get keyword: Defining New Widgets. (line 1314) * value-to-external keyword: Defining New Widgets. (line 1276) * value-to-internal keyword: Defining New Widgets. (line 1269) * variable: atoms. (line 1043) * variable-item: constants. (line 973) * vector: composite. (line 1090) * void keyword: menu-choice. (line 716) * widget browser: Widget Browser. (line 1364) * widget buttons: User Interface. (line 200) * widget library, why use it: Introduction. (line 103) * widget minor mode: Widget Minor Mode. (line 1384) * widget properties: Widget Properties. (line 1136) * widget-apply: Widget Properties. (line 1170) * widget-backward: User Interface. (line 267) * widget-browse: Widget Browser. (line 1369) * widget-browse-at: Widget Browser. (line 1377) * widget-browse-other-window: Widget Browser. (line 1373) * widget-button-click: User Interface. (line 211) * widget-button-click <1>: Setting Up the Buffer. (line 399) * widget-button-face: User Interface. (line 249) * widget-button-prefix: Basic Types. (line 446) * widget-button-press: User Interface. (line 205) * widget-button-press <1>: Setting Up the Buffer. (line 399) * widget-button-suffix: Basic Types. (line 449) * widget-children-validate: Basic Types. (line 567) * widget-choose: Utilities. (line 1406) * widget-create: Setting Up the Buffer. (line 374) * widget-default-delete: Defining New Widgets. (line 1292) * widget-default-format-handler: Defining New Widgets. (line 1329) * widget-delete: Setting Up the Buffer. (line 381) * widget-field-face: User Interface. (line 194) * widget-field-keymap: editable-field. (line 691) * widget-forward: User Interface. (line 263) * widget-get: Widget Properties. (line 1162) * widget-get-sibling: Utilities. (line 1402) * widget-global-map: Setting Up the Buffer. (line 404) * widget-image-directory: Basic Types. (line 595) * widget-image-enable: Basic Types. (line 600) * widget-insert: Setting Up the Buffer. (line 393) * widget-keymap: Setting Up the Buffer. (line 399) * widget-link-prefix: link. (line 616) * widget-link-suffix: link. (line 619) * widget-member: Widget Properties. (line 1167) * widget-minor-mode: Widget Minor Mode. (line 1388) * widget-minor-mode-keymap: Widget Minor Mode. (line 1392) * widget-mouse-face: User Interface. (line 252) * widget-parent-action: Defining New Widgets. (line 1339) * widget-prompt-value: Utilities. (line 1398) * widget-push-button-prefix: push-button. (line 654) * widget-push-button-suffix: push-button. (line 657) * widget-put: Widget Properties. (line 1158) * widget-radio-add-item: radio-button-choice. (line 778) * widget-setup: Setting Up the Buffer. (line 384) * widget-text-keymap: text. (line 701) * widget-type: Widget Properties. (line 1178) * widget-types-convert-widget: Defining New Widgets. (line 1252) * widget-types-copy: Defining New Widgets. (line 1266) * widget-value: Widget Properties. (line 1139) * widget-value-convert-widget: Defining New Widgets. (line 1255) * widget-value-set: Widget Properties. (line 1143) * widget-value-value-get: Defining New Widgets. (line 1320) * widgets, basic types: Introduction. (line 63) * widgets, programming example: Programming Example. (line 273)