term::interact::pager(n) Terminal control term::interact::pager(n)


term::interact::pager - Terminal widget, paging

package require Tcl 8.4

package require term::interact::pager ?0.1?

term::interact::pager object text ?options...?

object interact

object done

object clear

object text text

object configure

object configure option

object configure option value...

object cget option


This package provides a class for the creation of a simple paging text display.

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

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

The argument is the text to show, possibly followed by configuration options and their values. The options are explained in the section Configuration.

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

Show the pager in the screen at the configured location and start 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.
This method can be used by user supplied actions to terminate the interaction with the object.
This method can be used by user supplied actions to remove the pager from the terminal.
This method can be used to change the text shown by the pager. The pager will reset the dispay to show the first line of the text at the top.
Standard methods to retrieve and configure the options of the pager.

A pager instance recognizes the following options:

Specifies the channel to read character sequences from. Defaults to stdin.
Specifies the channel to write the pager contents to. Defaults to stdout.
Specifies the column of the terminal where the left margin of the pager display should appear. Defaults to 0, i.e. the left-most column.
Specifies the line of the terminal where the top margin of the pager display should appear. Defaults to 0, i.e. the top-most line.
Specifies the number of lines of text to show at most in the display. Defaults to 25.
Specifies a dictionary containing additional actions, using character sequences as keys. Note that these sequences cannot override the hardwired sequences described in section Interaction.

A pager 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.

The text is scrolled down a single line, making one more line visible at the top. The pager will not react if the first line of the text is already shown.
The text is scrolled up a single line, making one more line visible at the bottom. The pager will not react if the last line of the text is already shown.
The text is scrolled down a page. The pager will not react if the first line of the text is already shown.
The text is scrolled up a page. The pager will not react if the last line of the text is already shown.
The interaction with the object is terminated.

This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category term of the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883]. Please also report any ideas for enhancements you may have for either package and/or documentation.

control, pager, terminal, text display

Terminal control

Copyright (c) 2006 Andreas Kupries <andreas_kupries@users.sourceforge.net>
0.1 term