term::interact::menu - Terminal control

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# term::interact::menu(n) 0.1 tcllib "Terminal control"

## Name

term::interact::menu - Terminal widget, menu

## Synopsis

- package require Tcl 8.4
- package require term::interact::menu ?0.1?

- term::interact::menu object dict ?options...?
- object interact
- object done
- object clear
- object configure
- object configure option
- object configure option value...
- object cget option

## Description

This package provides a class for the creation of a simple menu control.

## Class API

The package exports a single command, the class command, enabling the creation of menu instances. Its API is:

term::interact::menu object dict ?options...?

  This command creates a new menu object with the name object, initializes it, and returns the fully qualified name of the object command as its result.

  The argument is the menu to show, possibly followed by configuration options and their values. The options are explained in the section Configuration. The menu is a dictionary maping labels to symbolic action codes.

## Object API

The objects created by the class command provide the methods listed below:

object interact

  Shows the menu in the screen at the configured location and starts interacting with it. This opens its own event loop for the processing of incoming characters. The method returns when the interaction has completed. See section Interaction for a description of the possible interaction.

  The method returns the symbolic action of the menu item selected by the user at the end of the interaction.

object done

  This method can be used by user supplied actions to terminate the interaction with the object.

object clear

  This method can be used by user supplied actions to remove the menu from the terminal.

object configure
object configure option
object configure option value...
object cget option

  Standard methods to retrieve and configure the options of the menu.

## Configuration

A menu instance recognizes the following options:

-in chan

  Specifies the channel to read character sequences from. Defaults to stdin.

-out chan

  Specifies the channel to write the menu contents to. Defaults to stdout.

-column int

  Specifies the column of the terminal where the left margin of the menu display should appear. Defaults to 0, i.e. the left-most column.

-line int

  Specifies the line of the terminal where the top margin of the menu display should appear. Defaults to 0, i.e. the top-most line.

-height int

  Specifies the number of lines of text to show at most in the display. Defaults to 25.

-actions dict

  Specifies a dictionary containing additional actions, using character sequences as keys. Note that these sequences cannot override the hardwired sequences described in section Interaction.

-hilitleft int
-hilitright int

  By default the entire selected menu entry is highlighted in revers output. However, when present these two options restrict revers dispay to the specified sub-range of the entry.

-framed bool

  By default the menu is shown using only header and footer out of characters box graphics. If this flag is set the menu is fully enclosed in a box.

## Interaction

A menu object recognizes the control sequences listed below and acts as described. The user can supply more control sequences to act on via the configuration, but is not able to overide these defaults.

Cursor Up

  The selection is moved up one entry, except if the first entry of the menu is already selected.

Cursor Down

  The selection is moved down one entry, except if the last entry of the menu is already selected.

Enter/Return

  The interaction with the object is terminated.

## Bugs, Ideas, Feedback

This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category term of the Tcllib Trackers. Please also report any ideas for enhancements you may have for either package and/or documentation.

When proposing code changes, please provide unified diffs, i.e the output of diff -u.

Note further that attachments are strongly preferred over inlined patches. Attachments can be made by going to the Edit form of the ticket immediately after its creation, and then using the left-most button in the secondary navigation bar.

## Keywords

control, menu, terminal, text display

## Category

Terminal control

## Copyright

Copyright © 2006 Andreas Kupries <andreas_kupries@users.sourceforge.net>