I don't know what you mean by trigger. 

#!/usr/bin/perl

# http://perlmonks.org/?node_id=1170638

use strict;
use warnings;
use Tk;
use Tk::JPEG;
use Image::Size;

my $file = '../smalltux.gif';
my ($w, $h) = imgsize($file);

my $mw = new MainWindow;

my $one = $mw->Frame()->pack;
my $labelone = $one->Label(-text => 'Panel One', -fg => 'red',
  )->pack(-side => 'left');
$one->Button(-text => 'On',
  -command => sub { $labelone->configure(-fg => 'green')},
  )->pack(-side => 'left');
$one->Button(-text => 'Off',
  -command => sub { $labelone->configure(-fg => 'red')},
  )->pack(-side => 'left');

my $c = $mw->Canvas(-width => $w, -height => $h )->pack();
my $im = $c->Photo(-file =>$file);
$c->createImage(0, 0, -image => $im, -anchor => 'nw');

my $two = $mw->Frame()->pack;
my $labeltwo = $two->Label(-text => 'Panel One', -fg => 'red',
  )->pack(-side => 'left');
$two->Button(-text => 'On',
  -command => sub { $labeltwo->configure(-fg => 'green')},
  )->pack(-side => 'left');
$two->Button(-text => 'Off',
  -command => sub { $labeltwo->configure(-fg => 'red')},
  )->pack(-side => 'left');

MainLoop;

[download]

In reply to Re^3: Feedback for programming a UI in Perl by Anonymous Monk
in thread Feedback for programming a UI in Perl by stevieb

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