#!/usr/bin/perl use strict; use Tk; my $mw = MainWindow->new(); $mw->protocol('WM_DELETE_WINDOW', \&ExitApplication); MainLoop(); sub ExitApplication {    # Prepare dialog yes|no    my $dialog = $mw->Dialog(-text => 'Do you really want to quit?',                             -bitmap => 'question',                             -title => 'Quit?',                             -default_button => 'Yes',                             -buttons => [qw/Yes No/],                            );    my $answer = $dialog->Show(); # and display dialog    if ($answer =~ /y/i){        # maybe do some cleaning up and        exit;    }    else {        # continue    } } # sub ExitApplication