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The class text-input-pane is a pane for entering a single line of text.









The text in the pane.


The position of the caret in the text (from 0).


The maximum number of characters allowed.


Controls the enabled state of the pane.


A function usually called when the user presses Return.


The type of arguments to callback .


A function called when a change is made.


The type of arguments to change-callback .


A function designator.


A function called to validate a change.

Note: Implemented for Motif only, not Microsoft Windows or Mac OS X.


A list of pairs ( gesture . callback ).


A function called to complete the text.


A function designator.


t, nil or a pathname designator.


A boolean.


A boolean.


A list of strings or the keyword :default.


A boolean.


A function called when certain keyboard gestures occur in the pane.


A function called when editing starts or stops.


A plist specifying buttons to add, or t or nil.


Along with the next four initargs, this is implemented only on Cocoa. It specifies that the pane has "recent-items", which also means using NSSearchField.


See :search-field above.


See :search-field above.


See :search-field above.


See :search-field above.






The class text-input-pane provides a great deal of flexibility in its handling of the text being entered. It starts with the initial text and caret-position specified by the arguments text and caret-position respectively. It limits the number of characters entered with the max-characters argument (which defaults to nil, meaning there is no maximum).

If enabled is nil, the pane is disabled. If enabled is :read-only, then the pane shows the text and allows it to be selected without it being editable. In this case the visual appearance varies between window systems, but often the text can be copied and the caret position altered. If enabled is any other true value, then the pane is fully enabled. The default value of enabled is t.

You can programmatically get and set the selection and caret position by set-text-input-pane-selection, text-input-pane-selected-text, text-input-pane-selection and text-input-pane-caret-position. You can programmatically perform standard edit operations by using text-input-pane-paste, text-input-pane-copy, text-input-pane-cut and text-input-pane-delete. You can programmatically invoke the completion functions by text-input-pane-complete-text and text-input-pane-in-place-complete.

For more than one line of input, use multi-line-text-input-pane.

Description: Callbacks

callback , if non-nil, is called when the user presses Return, unless navigation-callback is non-nil, in which case navigation-callback is called instead. If the pane has "recent-items" (implemented only on Cocoa) then the timing of calls to callback is modified: see the discussion of recent-items below for the details.

When the text or caret-position is changed, the callback change-callback is called with the text , the pane itself, the interface and the caret-position . The arguments that are passed to the change-callback can be altered by specifying the change-callback-type (see the callbacks class for details of possible values).

With the Motif implementation it is possible to check changes that the user makes to the text-input-pane by providing a confirm-change-function which gets passed the new text, the pane itself, its interface and the new caret position, and which should return non-nil if it is OK to make the change. If nil is returned, then the pane will be unaltered and a beep will be signalled to indicate that the new values were invalid.

gesture-callbacks provides callbacks to perform for specific keyboard gestures. Each gesture must be an object that sys:coerce-to-gesture-spec can coerce to a gesture-spec. Each callback can be a callable (symbol or function) which takes one argument, the pane. Alternatively each callback can be a list of the form ( function arguments ). Note that in this case, the pane itself is not automatically passed to the function amongst arguments .

When the user enters a gesture that matches gesture in any pair amongst gesture-callbacks , the callback is executed and the gesture is not processed any more.

text-change-callback is a change callback (see change-callback ) that is called only when the text in the pane changes. In contrast, change-callback is also called when the caret moves. If both text-change-callback and change-callback are supplied, only text-change-callback is invoked.

Notes: Callbacks
  1. change-callback is potentially called more than once for each user gesture.
  2. The interaction of in-place completion is implemented using gesture-callbacks . Gestures which you define explicitly by gesture-callbacks override the gestures which are defined implicitly by the in-place completion mechanism.
  3. For gestures that change the text, text-change-callback is probably better than gesture-callbacks .
Description: Completion

A completion-function can be specified which will get called when the completion gesture is made by the user (by pressing the Tab key) or when text-input-pane-complete-text is called. The function should have signature:

completion-function pane string => completions , start , end

where pane is the text-input-pane itself and string is the string to complete. When completion is invoked completion-function is called with pane and a string containing the text of pane to the left of the cursor.

The completion-function is called with the pane and the text to complete and should return either nil, the completed text as a string or a list completions of candidate completions. In the latter case, the CAPI will prompt the user for the completion they wish, and this will become the new text. In addition, the completion-function can return two more values, start and end , which specify a range in the text that is to be replaced if the completion is successful.

When complete-do-action is non-nil, completion of the text in the pane automatically invokes callback (if callback is non-nil). The default value of complete-do-action is nil.

in-place-completion-function tells the pane to do in-place completion and specifies the function to use. The function should have signature:

in-place-completion-function pane string => completions , start , end

where pane is the text-input-pane itself and string is the string to complete. When in-place completion is invoked in-place-completion-function is called with pane and a string containing the text of pane to the left of the cursor.

completions needs to be a list of strings that are possible completions, a single string that is a unique completion, or the symbol :destroy. :destroy means that the in-place completion needs to stop and close the in-place window. In addition, the completion function can return two more values, start and end , which specify a range in the text that is to be replaced if the completion is successful. The function is called repeatedly whenever there is a change to the text that should be completed.

The default value of in-place-completion-function is nil.

file-completion , if non-nil, tells the pane to do file completion using an in-place window. The user invokes In-place completion or file completion by pressing the Up or Down key. In-place completion for more details of the user interaction.

If file-completion is a pathname designator, its location is used as the root path for the completion.

The default value of file-completion is nil.

in-place-filter takes effect only when either in-place-completion-function or file-completion is non-nil. If in-place-filter is t then the in-place window can have a filter. Note that the filter needs to requested by a user gesture. Control+Return is the default in-place filter gesture. The default value of in-place-filter is t.

directories-only takes effect only if file-completion is used. If directories-only is t then in-place completion shows only directories. The default value of directories-only is nil.

ignore-file-suffices takes effect only if file-completion is used. It tells in-place completion to ignore files whose file namestring (the result of cl:file-namestring) ends with any of the strings in the list ignore-file-suffices . If ignore-file-suffices is :default, then completion uses the default value, which is the value of editor:*ignorable-file-suffices* (see config/a-dot-lispworks.lisp).

Notes: Completion
  1. If in-place-completion-function needs some dynamic information, it can put it in a property of the pane (using capi-object-property).
  2. For dynamic control over whether there is an in-place completion or not, specify an in-place-completion-function that simply returns the keyword :destroy when there should be no completion.
  3. The initarg :file-completion overrides :in-place-completion-function.
  4. The in-place completion mechanism uses gesture-callbacks to implement the functionality.
  5. :in-place-filter can be used to specify that the in-place window can have a filter.
  6. The behavior of in-place completion is somewhat different from other completion.
  7. The initargs :directories-only and :ignore-file-suffices can be used to change the behavior of the completion.
Description: Editing and navigation callbacks

navigation-callback , if non-nil, is a function that will be called when certain navigation gestures are used in the text-input-pane. The function is called with two arguments, the pane itself, and one of the following keywords:


Tab was pressed.


Tab Backwards (usually Shift+Tab) was pressed.


Return was pressed.


Shift+Return was pressed.


Enter was pressed.


Shift+Enter was pressed.

When navigation-callback is non-nil, it is called instead of callback when Return is pressed. callback is still called via an OK button if there is one (see buttons below).

navigation-callback is implemented only on Microsoft Windows and Cocoa.

editing-callback , if non-nil, is a function of two arguments:

editing-callback pane type

pane is the text-input-pane and type is a keyword. editing-callback is called with type :start when the user starts editing and type :end when the user stops editing. In general, this occurs when the focus changes, but on Cocoa type :start is passed when the first change is made to the text.

Notes: Editing and navigation callbacks

Enter is the key usually found on the numeric keypad.

Description: Buttons

buttons specifies toolbar buttons which appear next to the pane and facilitate user actions on it. It also specifies the position of the buttons relative to the pane. This feature appears in the LispWorks IDE, for example the Class box of the Class Browser.

The allowed keys and values of the plist buttons are:


A boolean or a plist, default value t. If true, a button which calls callback appears. If the value is a plist then this plist supplies details for the button, as described below.


A boolean or a plist, default value nil. If true, a button which calls cancel-function appears. A plist value is interpreted as for :ok and can also contain the key :accelerator which specifies an accelerator used for the button. There is no default accelerator.


A boolean or a plist. If true, a button which calls completion-function appears. The default value is t if completion-function is non-nil, and nil otherwise. A plist value is interpreted as for :ok.


A keyword or a plist. If true, a button which invokes prompt-for-file appears. If the value is :save or :open then it is passed as the operation argument to prompt-for-file, replacing the text in the pane if successful. If the value is a plist, then it supplies details for the button, as described below, and can also contain the keywords :message to specify a message for the file prompter; :pathname to specify the default pathname of the file prompter (defaults to the text in the text-input-pane), :directory to use prompt-for-directory rather than prompt-for-file, or any of the keywords :ok-check, :filter, :filters, :if-exists, :if-does-not-exist, :operation, :owner, :pane-args or :popup-args which are passed directly to prompt-for-file or prompt-for-directory.


A function that expects the pane as its single argument. The default is a function which sets text to the empty string.


Specifies a help button. The value must be a plist containing either keys :function and optionally :arguments, or the keys :title, :message and optionally :dialog-p.

If function is supplied, when the user presses the help button it calls

(apply function pane arguments )

where pane is the text-input-pane. title , message and dialog-p are ignored in this case.

Otherwise when the user presses the help button it opens a window with title title displaying the string message in a display-pane. The message can be long, and can include newlines. The window is owned by the pane, but is not modal, so the user can interact with the pane while the help window is displayed. If dialog-p is true, the help window is raised as a dialog. The default value for dialog-p is nil. function and arguments are ignored in this case.

The plist can contain other keys as described below.


The value is either :horizontal or :vertical. orientation controls the orientation of the toolbar. This is useful for multi-line-text-input-pane. The default value is :horizontal.


The value is :top, :center, :centre or :bottom. adjust controls how the buttons are adjusted vertically relative to the text input pane. This is useful for multi-line-text-input-pane. The default value is :center.


The value is :top, :bottom, :left or :right. position determines whether the buttons appear above, below, left or right of the text input pane. If :position is not supplied, then the buttons appear to the right of the pane.

The value nil for buttons means there are no buttons - this is the default. When buttons is true the buttons appear or not according to their specified values or their default values.

All of the button plists (for :ok, :cancel, :help and so on) can contain the following keys and values in addition to those mentioned above:


A value that controls whether the button is enabled. (See the reader text-input-pane-buttons-enabled).


The image to use for the button. This should be either a pathname or string naming an image file to load, a symbol giving the id of an image registered with register-image-translation, an image object as returned by load-image or an external-image. The default image is one of the symbols ok-button, cancel-button or complete-button, which are pre-registered image identifiers corresponding to each button.


The help-key used to find a tooltip for the button.

The reader text-input-pane-buttons-enabled returns a list containing keywords such as:ok, :cancel and :completion, one for each corresponding button (as specified by buttons ) that is currently enabled.

The writer (setf text-input-pane-buttons-enabled) takes a list of keywords as described for the reader and sets the enabled state of the buttons, enabling each button if it appears in the list and disabling it otherwise. The value t can also be passed: this enables all the buttons.

Description: Search field and recent items

If search-field is a string and recent-items-name is not supplied, then the value search-field is used as the name. See the discussion of recent-items below.

If any of search-field , recent-items or recent-items-name is supplied and is non-nil, the pane uses NSSearchField, and also has "recent items". An NSSearchField has a different appearance from text-input-pane, can display recent items menu, and its input behavior is a little different too.

If recent-items is non-nil, it must be a list of strings, or t. When it is a list of strings, it specifies the initial list of "recent items". When it is t, it simply specifies that the pane should handle recent items.

If recent-items-name is non-nil, it should be a string. The string specifies the autosave name of the pane. When a pane has an autosave name, Cocoa remembers the list of recent items for pane with the same autosave name and same application. The record persists between invocations of the application.

If recent-items-name is not supplied or is nil, and search-field is a string, it is used instead as the name.

The maximum number of recent items defaults to 50 and can be controlled by the initarg value maximum-recent-items . The value 0 can be used to switch off the "recent items" feature, including the menu.

The recent items list can be read and set by text-input-pane-recent-items, or modified by any of text-input-pane-replace-recent-items, text-input-pane-delete-recent-items, text-input-pane-append-recent-items, text-input-pane-prepend-recent-items and text-input-pane-set-recent-items.

The input behavior of text-input-pane with "recent items" is the same is that of other text-input-panes except for the timing of calls to callback . Note that this refers to the function that is passed with the initarg :callback, so change-callback is not affected.

By default, each time the user types a character it causes a scheduling of callback some short time later. If the user types another character before the callback, it is re-scheduled later. The result is that as long as the user types, there are no callbacks, but once the user stops a callback is generated.

The behavior of callback can be controlled by the initarg value recent-items-mode , which can be one of :explicit, :delayed or :immediate. :explicit gives the same behavior as a normal text-input-pane, :delayed is the default described above, and :immediate means doing a callback immediately after each character. In addition, when the user selects an item from the recent items menu or clicks its Cancel button, the callback is called. In the case of the Cancel button, the string would be empty.

(capi:contain (make-instance 'capi:text-input-pane
                             :text "Hello world"))
(setq tip (capi:contain
                        :enabled nil)))
  tip #'(setf capi:text-input-pane-enabled) t tip)
 tip #'(setf capi:text-input-pane-enabled) nil tip)
 tip #'(setf capi:text-input-pane-text) "New text" tip)
(capi:contain (make-instance
               :text "Hello world"
               :callback #'(lambda (text interface)
                              "Interface ~S's text: ~S"
                              interface text))))

This example uses a plist value for the buttons key :cancel to specify that the Cancel button is initially disabled:

 (make-instance 'capi:text-input-pane 
                '(:ok t :cancel (:enabled nil))))

This example shows how to specify a Help button which displays a help message:

(defvar *help-message* "A long help message.")
 (make-instance 'capi:text-input-pane
                  (:title "help window"
                   :message ,*help-message*))))

This example shows to specify a button which prompts for a directory:

 (make-instance 'capi:text-input-pane
                '(:browse-file (:directory t 
                                :image :std-file-open)
                  :ok nil))
  :title "Enter a directory path")

This example illustrates the use of gesture-callbacks . Ctrl+e moves the cursor to the end of the input, Ctrl+a moves it to the start, and Ctrl+6 does something else:

    #'(lambda (tip)
        (setf (capi:text-input-pane-caret-position tip)
              (length (capi:text-input-pane-text tip)))))
    #'(lambda (tip)
        (setf (capi:text-input-pane-caret-position tip)
    #\Ctrl-6 'do-something-else))))

There is a further example here:

(example-edit-file "capi/elements/text-input-pane")
See also

Controlling Mnemonics
Displaying and entering text
Matching resources for GTK+
Adding Toolbars
Toolbar items other than buttons with images
In-place completion

CAPI User Guide and Reference Manual (Windows version) - 25 Feb 2015