#!/usr/bin/perl -w
# Copyright 2008, 2010 Kevin Ryde
# This file is part of Chart.
#
# Chart is free software; you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation; either version 3, or (at your option) any later version.
#
# Chart is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along
# with Chart. If not, see <http://www.gnu.org/licenses/>.
use strict;
use warnings;
use Data::Dumper;
use Glib;
use Scalar::Util;
use Gtk2 '-init';
use Gtk2::Ex::TimerObject;
sub timer {
my @args = @_;
print "timer ", Dumper (\@args);
}
{
my $timer;
{
my $widget = Gtk2::Label->new;
$widget->signal_connect (destroy => sub { print "widget destroy\n"; });
$timer = $widget->{'timer'} = Gtk2::Ex::TimerObject->new
(period => 1000,
callback => \&timer,
userdata => $widget,
weak => 1);
}
Gtk2->main;
exit 0;
}
{
my $widget = Gtk2::Label->new;
my $weak_widget = $widget;
Scalar::Util::weaken ($weak_widget);
my $id = Glib::Timeout->add (1000, \&timer, $weak_widget);
Gtk2->main;
exit 0;
}
__END__
{
{
my $widget = Gtk2::Label->new;
$widget->signal_connect (destroy => sub { print "label destroy\n"; });
my $id = Gtk2::Ex::TimerObject::timeout_add_weak (1000, \&timer, $widget);
}
Gtk2->main;
exit 0;
}
#------------------------------------------------------------------------------
# generic weakened callback
sub _weak_callback {
my @args = @_;
my $wdata = $args[$#args];
my $userdata = $wdata->[1];
if (! defined $userdata) { return 0; }
$args[$#args] = $userdata;
return &{$wdata->[0]} (@args);
}
sub weak_callback {
my ($period, $callback, $userdata, @optional_priority) = @_;
if (ref $userdata) {
my @wdata = ($callback, $userdata);
Scalar::Util::weaken ($wdata[1]);
return (\&_weak_callback, \@wdata);
} else {
return ($callback, $userdata);
}
}
# $self->{'timer_id'} = Glib::Timeout->add
# ($period, weak_callback(\&_timer_object_callback,$self), @optional_priority);
#------------------------------------------------------------------------------
# integer ID, with weak reference to userdata
sub timeout_add_weak {
my ($period, $callback, $userdata, @optional_priority) = @_;
if (ref $userdata) {
my @wdata = ($callback, $userdata);
Scalar::Util::weaken ($wdata[1]);
$callback = \&_timeout_weak_callback;
$userdata = \@wdata;
}
return Glib::Timeout->add ($period, $callback, $userdata,
@optional_priority);
}
sub _timeout_weak_callback {
my ($wdata) = @_;
if (! defined $wdata->[1]) {
print "userdata garbage collected, stopping\n";
return 0;
}
return (&{$wdata->[0]} ($wdata->[1]));
}