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NAME

Tie::Wx::Widget - implicit access value of a Wx widget

SYNOPSIS

    use Tie::Wx::Widget;

    tie $tiedwidget, Tie::Wx::Widget, $widget;

    $tiedwidget = 7;       # instead of $widgetref->SetValue(7);

    say $tiedwidget;       # instead of say $widgetref->GetValue;

    untie $tiedwidget;     # now $tiedwidget is a normal scalar again (not required)

CALLBACKS

Often are the widget values coupled with each other. For instance in App::Spirograph is a slider, which max value is the value of another slider. Once you know this, why keep track of it and change the range by hand any given time?

    tie $tslider, Tie::Wx::Widget, $slider,
        sub { $[0]->SetValue($[1]); $subslider->SetRange(1, $[1]) };

The first parameter to the callback is always the Wx object reference, the assign-callback gets also a second with the assigned value. Own callbacks replace the the ones, generated by default.

The complete parameter list is is:

    tie $tw, Tie::Wx::Widget, $widget, [&$do_when_assign, &$do_when_retrieve];

Yes, its also doable with events, but thats also more syntax than this. Plus, its a different event for many widgets, why remember this? Plus, a tied widget still gives you the freedom to change the value under the radar. See section "INTERNALS" for more.

WARNINGS

Your program will die, if you don't provide a proper Wx widget, that has a GetValue and SetValue method, or the callbacks are no coderef. Unless you init with:

    use Tie::Wx::Widget 'warn_mode';

or do later:

    Tie::Wx::Widget::warn_mode();

Then will be called warn instead of die. But you can switch anytime back with:

    Tie::Wx::Widget::die_mode();

Wich has only effect for all variables tied afterwards. Because if the Wx ref is not good, there will be no tying anyway.

INTERNALS

    # how to get a reference to the Tie::Wx::Widget object ?
    $tieobject = tie $tiedwidget, Tie::Wx::Widget, $widget;
    $tieobject = tied $tiedwidget;

    # now you even can:
    $tieobject->FETCH()
    # aka:
    $tieobject->{'widget'}->GetValue;
    # or do any other method on the wx object
    $tieobject->{'w'}->Show(0);
    # works too (hides the widget)
    $tieobject->STORE(7);

    # doesn't do anything
    $tieobject->DESTROY()

ACKNOWLEDGEMENTS

This was solely my idea before Linuxtag 2011. Started as a slide for my talk there.

AUTHOR

Herbert Breunung, <lichtkind at cpan.org>

LICENSE AND COPYRIGHT

Copyright 2011-2022 Herbert Breunung.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.