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UI-Various-1.00
River stage zero No dependents
1 ++
/ UI::Various::Curses::base

NAME

UI::Various::Curses::base - abstract helper class for Curses's UI elements

SYNOPSIS

    # This module should only be used by the UI::Various::Curses UI
    # element classes!

ABSTRACT

This module provides some helper functions for the UI elements of the Curses::UI GUI.

DESCRIPTION

The documentation of this module is only intended for developers of the package itself.

All functions of the module will be included as second "base class" (in @ISA). Note that this is not a diamond pattern as this "base class" does not import anything besides Exporter, though it add a common private attribute to all UI::Various::Curses classes:

Attributes

_cui [rw, optional]

a reference to the main Curses::UI element used for the implementation of the UI element

Note that usually this should only be used within UI::Various::Curses.

_cid [ro, auto]

a unique ID needed for accessing some Curses::UI methods, most notably delete

Note that we can't simply use our own object ($self) as Curses::UI uses the class-name if it encounters an object as ID.

METHODS

The module also provides the following common (internal) methods for all UI::Various::Curses UI element classes:

_cleanup - cleanup UI element

    $ui_element->cleanup;

description:

This method prepares a UI element for destruction by removing all of the references it is holding (including its parent reference). An object will therefore only survive if it is additionally still referenced outside of UI::Various, e.g. a variable used to create it in the first place.

_reference - remember SCALAR referenece

    $self->_reference($scalar, $update);

parameters:

    $self               reference to derived object
    $scalar             reference to SCALAR
    $update             flag to initiate update of objects using same SCALAR

description:

This method stores all SCALAR references for later updates when the content of a SCALAR is changes. If the optional update flag is set (to any true value) all other references are updated (by calling their _update method).

_update_all_references - update all SCALAR refereneces

    $self->_update_all_references();

parameters:

    $self               unused reference object

description:

This method updates all stored SCALAR references for all objects. Currently it's only used after destroying a UI::Various::Curses::Dialog.

_common_attributes - compute array of common Curses::UI attributes

    my @attributes = $ui_element->_common_attributes();

description:

This method returns an array of attributes of a UI element that are common to all Curses::UI widgets.

_needed_width - determine needed width of UI element

    $ui_element->_needed_width();

description:

This method updates determines the width a UI element needs, which is either specified explicitly or the maximum width of its text lines (with possible embedded newlines).

SEE ALSO

UI::Various

LICENSE

Copyright (C) Thomas Dorner.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See LICENSE file for more details.

AUTHOR

Thomas Dorner <dorner (at) cpan (dot) org>