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NAME

README - This file provides out of bounds mechanics.

DESCRIPTION

This document describes the main features of the out-of-bounds mechanics that extends the bind and bindtags functions.

The bound method associates callbacks with X events in the same manner as bind does. For example :

$widget->bound(tag,sequence,oob,callback)

If oob is specified, bound will arrange for oob to be evaluated whenever the event(s) given by sequence occur in the window(s) identified by $widget or tag. If oob is an empty string then the current binding for sequence is destroyed, leaving sequence bound less. In all of the cases where a oob argument is provided, bind returns an empty string. If oob is specified and evaluated to a valid out of bounds bit mask, then bound will arrange for callback to be called, if specified, for the previous callback to be called otherwise.

The boundtags method associates callbacks with X events in the same manner as bindtags does. For example :

$widget->boundtags([tagList],[levellist]);

When a bounding is created with the bound command, it is associated either with a particular window such as $widget, a class name such as Tk::Button, the keyword all, or any other string. All of these forms are called bounding tags. Each window has a list of bounding tags and levels that determine how events are processed for the window. When an event occurs in a window, it is applied to each of the window's tags in order: for each tag, the most specific bounding that matches the given tag and event is executed. See the Tk::bound documentation for more information on the matching process.

In addition, Tk::Bounded is used with Perl's multiple inheritance to override some methods normally inherited from Tk::Derived and Tk::Widget. It also specifies level 1 bound tags for caller class.

AUTHOR

Copyright (c) 2000-2007 Meccanomania