The London Perl and Raku Workshop takes place on 26th Oct 2024. If your company depends on Perl, please consider sponsoring and/or attending.


Gtk2::GladeXML - Create user interfaces directly from Glade XML files.


  # for a pure gtk+ glade project
  use Gtk2 -init;
  use Gtk2::GladeXML;
  $gladexml = Gtk2::GladeXML->new('');
  $quitbtn = $gladexml->get_widget('Quit'); 

  # for glade files using gnome widgets, you must initialize Gnome2
  # before loading the glade file.
  use Gnome2;
  use Gtk2::GladeXML;
  # this call also initializes gtk+ for us
  Gnome2::Program->init ($appname, $version);
  $gladexml = Gtk2::GladeXML->new('');


Gtk2::GladeXML allows Perl programmers to use libglade, a C library which generates graphical user interfaces directly from the XML output of the Glade user interface designer.


Glade is a free user interface builder for GTK+ and GNOME. After designing a user interface with glade-2 the layout and configuration are saved in an XML file. libglade is a library which knows how to build and hook up the user interface described in the Glade XML file at application run time.

This extension module binds libglade to Perl so you can create and manipulate user interfaces in Perl code in conjunction with Gtk2 and even Gnome2. Better yet you can load a file's contents into a PERL scalar do a few magical regular expressions to customize things and the load up the app. It doesn't get any easier.


$gladexml = Gtk2::GladeXML->new(GLADE_FILE, [ROOT, DOMAIN])

Create a new GladeXML object by loading the data in GLADE_FILE. ROOT is an optional parameter that specifies a point (widget node) from which to start building. DOMAIN is an optional parameter that specifies the translation domain for the xml file.

$gladexml = Gtk2::GladeXML->new_from_buffer(BUFFER, [ROOT, DOMAIN])

Create a new GladeXML object from the scalar string contained in BUFFER. ROOT is an optional parameter that specifies a point (widget node) from which to start building. DOMAIN is an optional parameter that specifies the translation domain for the xml file.

$widget = $gladexml->get_widget(NAME)

Return the widget created by the XML file with NAME or undef if no such name exists.

$gladexml->signal_autoconnect($callback[, $userdata])

Iterates over all signals and calls the given callback:

   sub example_cb {
      my ($name, $widget, $signal, $signal_data, $connect, $after, $userdata) = @_;

The following two convenience methods use this to provide a more convenient interface.

$gladexml->signal_autoconnect_from_package([PACKAGE or OBJECT])

Sets up the signal handling callbacks as specified in the glade XML data.

The argument to this method can be a Perl package name or an object. If a package name is used, each handler named in the Glade XML data will be called as a subroutine in the named package. If an object is supplied each handler will be called as a method of the object. If no argument is supplied, the name of the calling package will be used. A user data argument cannot be supplied however this is seldom necessary when an object is used.

The names of the subroutines or methods must exactly match the handler name in the XML data. It is worth noting that callbacks you get for free in c such as gtk_main_quit will not exist in perl and must always be defined, for example:

  sub gtk_main_quit

Otherwise behavior should be exactly as expected with the use of libglade from a C application.

$gladexml->signal_autoconnect_all (name => handler, ...)

Iterates over all named signals and tries to connect them to the handlers specified as arguments (handlers not given as argument are being ignored). This is very handy when implementing your own widgets, where you can't use global callbacks.

$widget = Gtk2::Glade->set_custom_handler ($callback[, $userdata])

This method tells Gtk2::GladeXML how to create handlers for custom widgets.

You can specify a "custom" widget in a glade file, which allows you to include in your interface widgets that Glade itself doesn't know how to create. To tell libglade how to instantiate such widgets, you specify a "custom widget handler", a function which returns a Gtk2:Widget object for that custom widget. This handler needs to be installed sometime before the instantiation of your Gtk2::GladeXML object, by calling set_custom_handler.

    my $widget = Gtk2::Glade->set_custom_handler( \&my_handler );
    my $gladexml = Gtk2::GladeXML->new( '' );

The prototype for the custom handler is:

    sub my_handler {
        my ($xml,       # The Gtk2::GladeXML object
            # the remaining arguments are as specified in the glade file:
            $func_name, # The function name
            $name,      # the name of the widget to be created
            $str1,      # the string1 property
            $str2,      # the string2 property
            $int1,      # the int1 property
            $int2,      # the int2 property
            $userdata   # the data passed to set_custom_handler
           ) = @_;
        return $widget; # a new Gtk2::Widget; you must call ->show on it.


Where is the option to generate Perl source in Glade?

Glade itself only creates the XML description, and relies on extra converter programs to write source code; only a few converters are widely popular.

In general, however, you don't want to generate source code for a variety of reasons, mostly to do with maintainability. This message on the glade-devel list explains it best:

Why does my program crash on startup?

Does your glade file use Gnome widgets? If so, you must initialize Gnome manually; libglade can knows how to create gnome widgets, but can't know how you want to initialize the app. This is usually sufficient:

  use Gnome2;
  Gnome2::Program->init ($app_name, $version_string);

Libglade's API reference mentions this:


perl(1), Glib(3pm), Gtk2(3pm)

The Libglade Reference Manual at


Ross McFarland <rwmcfa1 at neces dot com>, Marc Lehmann <>, muppet <scott at asofyet dot org>. Bruce Alderson provided several examples. Grant McClean <grant at mclean dot net dot nz> and Marco Antonio Manzo <amnesiac at perl dot org dot mx> contributed documentation.


Copyright 2003-2005 by the gtk2-perl team.

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This library 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 Library General Public License for more details.

You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307 USA.