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From the GTK+ website:

GTK+, or the GIMP Toolkit, is a multi-platform toolkit for creating graphical user interfaces. Offering a complete set of widgets, GTK+ is suitable for projects ranging from small one-off tools to complete application suites.

GTK+, The GIMP Toolkit, was initially made by the GNU Project for the GIMP but is now a very popular toolkit with bindings for many languages. This article will explore the tools used to configure the GTK+ theme, style, icon, font and font size, and also detail manual configuration.

Configuration programs

These GUI programs allow theme selection and at least customising of a font. They generally overwrite the ~/.gtkrc-2.0 file.

Note: As ~/.gtkrc-2.0 and other user theme files are not read by other accounts, the custom theme will not apply to X applications run as root. Possible solutions include:
  • Create symlinks, e.g
# ln -s /home/USER/.gtkrc-2.0 /root/.gtkrc-2.0
  • Adjust the theme as root
# gksu lxappearance
  • Use a settings daemon (this is what most desktop environments do). A desktop-agnostic variant using XSETTINGS is available in the AUR under xsettingsd-gitAUR.

See also Uniform Look for Qt and GTK Applications#Changing styles in each toolkit.


GTK+ 1.x

There are loads of GTK+ 1.x themes in the AUR: search for gtk-theme. A good start is gtk-smooth-engineAUR.

Most major desktop environments provide tools to configure the GTK+ theme, icons, font and font size.

Alternatively, use gtk-theme-switch2. Run it with the switch command.

GTK+ 2.x

There are loads of GTK+ 2.x themes in the AUR: search for gtk2-theme. A good start is gtk-engines which includes the popular Clearlooks theme.

Most major desktop environments provide tools to configure the GTK+ theme, icons, font and font size.

Alternatively, GTK+ settings can be configured manually by editing ~/.gtkrc-2.0. A list of GTK+ settings can be found in the GNOME library. To manually change the GTK+ theme, icons, font and font size, add the following to ~/.gtkrc-2.0:

gtk-icon-theme-name = "[name-of-icon-theme]"
gtk-theme-name = "[name-of-theme]"
gtk-font-name = "[font-name] [size]"

For example:

gtk-icon-theme-name = "Tango"
gtk-theme-name = "Murrine-Gray"
gtk-font-name = "DejaVu Sans 8"
Note: The above example requires the packages ttf-dejavu, tangerine-icon-theme, gtk-engine-murrine from the official repositories, and gtk-theme-murrine-collectionAUR from the AUR.

Another example:

# GTK theme
include "/usr/share/themes/Clearlooks/gtk-2.0/gtkrc"

# Font
style "myfont" {
    font_name = "DejaVu Sans 8"
widget_class "*" style "myfont"
gtk-font-name = "DejaVu Sans 8"

# Icon theme
gtk-icon-theme-name = "Tango"

# Toolbar style
gtk-toolbar-style = GTK_TOOLBAR_ICONS
  • The icon theme name is the name defined in the theme's index file, not the name of its directory.
  • If you edit your .gtkrc-2.0 file, only newly started applications will display the changes.

GTK+ 3.x

A good start is gnome-themes-standard which includes the popular Adwaita theme.

If selected style has both GTK+ 2.x and GTK+ 3.x themes, they will be used. If selected style has only GTK+ 2.x theme, it will be used for GTK+ 2.x applications and (ugly) defaults will be used for GTK+ 3.x applications. If selected style has only GTK+ 3.x theme, it will be used for GTK+ 3.x applications and (ugly) defaults will be used for GTK+ 2.x applications. Thus for uniform UI appearance and best experience one can use style that has both GTK+ 2.x and GTK+ 3.x themes.

Most major desktop environments provide tools to configure the GTK+ theme, icons, font and font size. If you use GNOME, use GNOME Tweak Tool: install gnome-tweak-tool. If you use Xfce, use the Appearance tool: go to Settings > Appearance.

An alternative without huge dependencies is lxappearance.

If you prefer not to install a theme manager at all, your theme can be set manually in $XDG_CONFIG_HOME/gtk-3.0/settings.ini (this is usually ~/.config/gtk-3.0/settings.ini). An example settings.ini file:

gtk-application-prefer-dark-theme = false
gtk-theme-name = Zukitwo
gtk-fallback-icon-theme = gnome
gtk-icon-theme-name = [icon theme name]
gtk-font-name = [font name] [font size]

A full example of a custom theme as converted from GTK+ 2.x to GTK+ 3.x by lxappearance:

gtk-font-name=Luxi Sans 12

If it still does not change, delete old gtk-3.0 folder in $XDG_CONFIG_HOME and copy gtk-3.0 folder from /path/to/theme to $XDG_CONFIG_HOME. Example:

$ rm -r ~/.config/gtk-3.0/
$ cp -r /usr/share/themes/Zukitwo/gtk-3.0/ ~/.config/  

After this, you need to set the same theme in your DE's appearance configuration tool. There are only a few themes which provide a uniform look for GTK+ 3.x and GTK+ 2.x apps. A few examples:

  1. Adwaita (part of gnome-themes-standard)
  2. Clearlooks-Phenix (AUR: clearlooks-phenix-gtk-themeAUR)
  3. Newlooks for GTK+ 3 and Clearlooks for GTK+ 2
  4. Zukitwo (zukitwo-themesAUR)
  5. Elegant Brit
  6. Atolm
  7. Hope
  8. OMG
  • Some themes may require librsvg to display correctly, but not all specify it as a dependency. Try installing it if the chosen theme looks broken.
  • There probably are other themes. Some of these themes are available in the AUR. Also, some of them are not usable as-is for displaying a GTK+ 2.x panel (light text over light background), so you need to use the provided panel background.

You could find what themes installed on your system have both an GTK+ 2.x and GTK+ 3.x version by using this command (does not work with names containing spaces):

find $(find ~/.themes /usr/share/themes/ -wholename "*/gtk-3.0" | sed -e "s/^\(.*\)\/gtk-3.0$/\1/")\
-wholename "*/gtk-2.0" | sed -e "s/.*\/\(.*\)\/gtk-2.0/\1"/

GTK+ and Qt

If you have GTK+ and Qt (KDE) applications on your desktop then you know that their looks do not blend well. If you wish to make your GTK+ styles match your Qt styles please read Uniform Look for Qt and GTK Applications.

GTK+ and HTML with Broadway

The GDK Broadway backend provides support for displaying GTK+ applications in a web browser, using HTML5 and web sockets. [1]

When using broadwayd, specify the display number to use, prefixed with a colon, similar to X. The default display number is 1.

$ display_number=:5

Start it.

$ broadwayd $display_number 

Port Used on default

port = 8080 + ($display_number - 1)

Point your browser to http://localhost:port

To Start apps

$ GDK_BACKEND=broadway BROADWAY_DISPLAY=$display_number <<app>>

Alternatively can set address and port

$ broadwayd --port $port_number --address $address $display_number

Configuration file

Note: See the GtkSettings properties in the GTK+ programming reference manual for the full list of GTK configuration options.

The purpose of this section is to collect GTK+ configuration settings which can e.g. be used within one's GTK+ configuration files.

There are two relevant locations for GTK+ configuration files (which are in an ini format) : $XDG_CONFIG_HOME/gtk-3.0/ (usually ~/.config/gtk-3.0/) and /etc/gtk-3.0/. The former is reserved for user wide settings, and the latter for system wide settings.

Enabling Customizable Keyboard Shortcuts

You can customize your GTK+ applications' keyboard shortcuts (those are called accelerators in GTK+ terminology) by hovering your mouse over a menu item and pressing your desired key combination. However, this feature is disabled by default. To enable it, set

gtk-can-change-accels = 1

Speed up your GNOME menu

This setting controls the delay between you pointing the mouse at a menu and that menu opening in GNOME. Change this to a setting you prefer. I guess the number is in milliseconds, e.g. 250 being a quarter of a second.

gtk-menu-popup-delay = 0

Reduce widget sizes

If you have a small screen or you just do not like big icons and widgets, you can resize things easily. To have icons without text in toolbars, use

gtk-toolbar-style = GTK_TOOLBAR_ICONS

To use smaller icons, use a line like this:

gtk-icon-sizes = "panel-menu=16,16:panel=16,16:gtk-menu=16,16:gtk-large-toolbar=16,16\

Or to remove icons from buttons completely:

gtk-button-images = 0

You can also remove icons from menus:

gtk-menu-images = 0

There is some more tweaking to do in your themes gtkrc like explained here and there's another theme that does it all.


Client-side decorations

GTK 3.12 introduced client-side decorations, which move the title-bar away from the window manager. This only works correctly in GNOME. Other environments may suffer from double title-bars or no title-bar at all. Some composite managers also conflict.

gtk3-noforcedcsdAUR from the AUR disables client-side decorations through the GTK_DISABLE_CSD variable.

Enable cedilla ç/Ç instead of ć/Ć

When you select the keyboard layout "U.S., alternative international" in Settings --> Keyboard --> Layout to enable accents, the typical combination for the cedilla ' + c results in ć instead of ç.

To change this suffice edit files gtk.immodules for gtk-2.0 and immodules.cache for gtk-3.0 in line that contains "cedilla" adding both "en" in the list "az:ca:co:fr:gv:oc:pt:sq:tr:wa" but in alphabetical order, staying that way in /etc/gtk-2.0/gtk.immodules

"cedilla" "Cedilla" "gtk20" "/usr/share/locale" "az:ca:co:en:fr:gv:oc:pt:sq:tr:wa"

and this in /usr/lib/gtk-3.0/3.0.0/immodules.cache

"cedilla" "Cedilla" "gtk30" "/usr/share/locale" "az:ca:co:en:fr:gv:oc:pt:sq:tr:wa"

Then, do

# echo "export GTK_IM_MODULE=cedilla" >> /etc/environment

Done. Simply just close and reopen the gtk programs like gedit.


When writing a start-from-scratch GTK+ 3 program with C, it's necessary to add CFLAGS for gcc:

$ gcc -g -Wall $(pkg-config --cflags --libs gtk+-3.0) -o base base.c

-g and -Wall parameters are not necessary since they are only for verbose debugging outputs. You may try out the official Hello World example.

Write a simple message dialog app

You can write your own GTK+ 3 message dialog easily in many programming languages through GObject-Introspection or bindings, or you can simply use bash.

The following examples display a simple "Hello world" in a message dialog.


  • Dependency: gtkadaAUR from AUR
  • Makedependency: gcc-ada
  • Build with: gnatmake hello_world `gtkada-config`
with Gtk.Main;
with Gtk.Dialog;           use Gtk.Dialog;
with Gtk.Message_Dialog;   use Gtk.Message_Dialog;

procedure hello_world is
  Dialog   : Gtk_Message_Dialog;
  Response : Gtk_Response_Type;
  Gtk_New (Dialog   => Dialog,
           Parent   => null,
           Flags    => 0,
           The_Type => Message_Info,
           Buttons  => Buttons_OK,
           Message  => "Hello world!");
  Format_Secondary_Markup (Dialog, "This is an example dialog.");
  Response := Run (Dialog);
end hello_world;

zenity --info --title='Hello world!' --text='This is an example dialog.'


  • Dependency: gtk-sharp-3 (and boo)
  • Makedependency: boo
  • Build with: booc
  • Run with: mono hello_world.exe (or booi
import Gtk from "gtk-sharp"
Hello = MessageDialog(null, DialogFlags.Modal, MessageType.Info, ButtonsType.Ok, "Hello world!")
Hello.SecondaryText = "This is an example dialog."


  • Dependency: gtk3
  • Build with: gcc -o hello_world $(pkg-config --cflags --libs gtk+-3.0) hello_world.c
#include <gtk/gtk.h>
int main (int argc, char *argv[]) {
	gtk_init (&argc, &argv);
        GtkWidget *hello = gtk_message_dialog_new (NULL, GTK_DIALOG_MODAL, GTK_MESSAGE_INFO, GTK_BUTTONS_OK, "Hello world!");
	gtk_message_dialog_format_secondary_text (GTK_MESSAGE_DIALOG (hello), "This is an example dialog.");
        gtk_dialog_run(GTK_DIALOG (hello));
        return 0;


  • Dependency: gtkmm3
  • Build with: g++ -o hello_world $(pkg-config --cflags --libs gtkmm-3.0)
#include <gtkmm/main.h>
#include <gtkmm/messagedialog.h>
int main(int argc, char *argv[]) {
	Gtk::Main kit(argc, argv);
	Gtk::MessageDialog Hello("Hello world!", false, Gtk::MESSAGE_INFO, Gtk::BUTTONS_OK);
	Hello.set_secondary_text("This is an example dialog.");;


  • Dependency: gtk-sharp-3
  • Build with: mcs -pkg:gtk-sharp-3.0 hello_world.cs
  • Run with: mono hello_world.exe
using Gtk;
public class HelloWorld {
	static void Main() {
		Application.Init ();
		MessageDialog Hello = new MessageDialog (null, DialogFlags.Modal, MessageType.Info, ButtonsType.Ok, "Hello world!");
		Hello.SecondaryText="This is an example dialog.";
		Hello.Run ();


  • Dependency: gtk-sharp-3
  • Makedependency: cobraAUR from AUR
  • Build with: cobra -c hello_world
  • Run with: mono hello_world.exe
@args -pkg:gtk-sharp-3.0
use Gtk

class HelloWorld
    def main
        hello = MessageDialog(nil, DialogFlags.Modal, MessageType.Info, ButtonsType.Ok, "Hello world!")
        hello.secondaryText = "This is an example dialog."


  • Dependency: gtkdAUR from AUR
  • Makedependency: dmd
  • Build with: dmd hello_world $(pkg-config --cflags --libs gtkd-2)
import gtk.Main;
import gtk.MessageDialog;

void main(string[] args)
	MessageDialog dialog = new MessageDialog(null, GtkDialogFlags.MODAL, MessageType.INFO, ButtonsType.OK, "Hello world!");;


  • Dependency: gtk-sharp-3
  • Makedependency: fsharpAUR from AUR
  • Build with: fsharpc -r:gtk-sharp.dll -I:/usr/lib/mono/gtk-sharp-3.0/
  • Run with: mono hello_world.exe
open Gtk
let Hello = new MessageDialog(null, DialogFlags.Modal, MessageType.Info, ButtonsType.Ok, "Hello world!")
Hello.SecondaryText <- "This is an example dialog."
Hello.Run() |> ignore


  • Dependency: gtk-3-fortran-gitAUR from AUR
  • Makedependency: gcc-fortran
  • Build with: gfortran hello_world.f90 -o hello_world $(pkg-config --cflags --libs gtk-3-fortran)
program hello_world
  use gtk_hl
  use gtk, only: gtk_init

  integer(c_int) :: resp
  character(40), dimension(2) :: msg

  call gtk_init()
  msg(1) ="Hello world!"
  msg(2) = "This is an example dialog."
  resp = hl_gtk_message_dialog_show(msg, GTK_BUTTONS_OK, type=GTK_MESSAGE_INFO)
end program hello_world


  • Dependency: gtk3
  • Makedependency: vala
  • Build with: valac --pkg gtk+-3.0
	Gtk.init (ref args)
	var Hello=new MessageDialog (null, Gtk.DialogFlags.MODAL, Gtk.MessageType.INFO, Gtk.ButtonsType.OK, "Hello world!")
	Hello.format_secondary_text ("This is an example dialog.") ()


  • Dependency: gtk3
  • Makedependency: gotk3-gitAUR from AUR
  • Build with: go build hello_world.go
  • (Or run with: go run hello_world.go)
package main
import ("")

func main() {
	dialog := gtk.MessageDialogNew(nil, gtk.DIALOG_MODAL, gtk.MESSAGE_INFO, gtk.BUTTONS_OK, "Hello world!")
	dialog.FormatSecondaryText("This is an example notification.")


  • Dependencies: groovy, java-gnomeAUR from AUR
  • Build with: groovyc -cp /usr/share/java/gtk.jar HelloWorld.groovy && jar cfe HelloWorld.jar HelloWorld HelloWorld.class
  • Run with: java -cp /usr/share/groovy/embeddable/groovy-all.jar:/usr/share/java/gtk.jar:HelloWorld.jar HelloWorld (or groovy -cp /usr/share/java/gtk.jar HelloWorld.groovy)
import org.gnome.gtk.*
def Hello = new InfoMessageDialog(null, "Hello world!", "This is an example dialog.")


  • Dependency: gtk3
  • Makedependency: haskell-gtk3AUR from AUR
  • Build with: ghc hello_world
import Graphics.UI.Gtk

main = do
	dialog <- messageDialogNew Nothing [DialogModal] MessageInfo ButtonsOk "Hello world!"
	messageDialogSetSecondaryText dialog "This is an example dialog."
	_res <- dialogRun dialog
	return 0


  • Dependency: java-gnomeAUR from AUR
  • Makedependency: java-environment
  • Build with: javac -cp /usr/share/java/gtk.jar && jar cfe HelloWorld.jar HelloWorld HelloWorld.class
  • Run with: java -cp /usr/share/java/gtk.jar:HelloWorld.jar HelloWorld
import org.gnome.gtk.Gtk;
import org.gnome.gtk.Dialog;
import org.gnome.gtk.InfoMessageDialog;

public class HelloWorld {
    public static void main(String[] args) {
        Dialog Hello = new InfoMessageDialog(null, "Hello world!", "This is an example dialog.");;


const Gtk =
Gtk.init(null, null)
var Hello = new Gtk.MessageDialog({type: Gtk.MessageType.INFO,
                                   buttons: Gtk.ButtonsType.OK,
                                   text: "Hello world!",
                                   "secondary-text": "This is an example dialog."})


lgi = require 'lgi'
Gtk = lgi.require('Gtk')
Hello=Gtk.MessageDialog {message_type = Gtk.MessageType.INFO,
                         buttons = Gtk.ButtonsType.OK,
                         text = "Hello world!",
                         secondary_text = "This is an example dialog."}


program	hello_world;
uses	Math, Gtk3;
var	dialog: PGtkWidget;
	SetExceptionMask([exInvalidOp, exDenormalized, exZeroDivide, exOverflow, exUnderflow, exPrecision]);
	gtk_init(@argc, @argv);
	dialog := gtk_message_dialog_new(nil, GTK_DIALOG_MODAL, GTK_MESSAGE_INFO, GTK_BUTTONS_OK, '%s', ['Hello world!']);
	gtk_message_dialog_format_secondary_text(PGtkMessageDialog(dialog), '%s', ['This is an example dialog.']);

use Gtk3 -init;
my $hello = Gtk3::MessageDialog->new (undef, 'modal', 'info', 'ok', "Hello world!");
$hello->set ('secondary-text' => 'This is an example dialog.');

from gi.repository import Gtk
Hello=Gtk.MessageDialog(None, Gtk.DialogFlags.MODAL, Gtk.MessageType.INFO, Gtk.ButtonsType.OK, "Hello world!")
Hello.format_secondary_text("This is an example dialog.")


require 'gtk3'
Hello = => :info,
                               :buttons_type => :ok,
                               :message => "Hello world!")
Hello.secondary_text = "This is an example dialog."


  • Dependency: java-gnomeAUR from AUR (and scala)
  • Makedependency: scala
  • Build with: scalac -cp /usr/share/java/gtk.jar -d HelloWorld.jar HelloWorld.scala
  • Run with: java -cp /usr/share/java/gtk.jar:HelloWorld.jar HelloWorld (or scala -cp /usr/share/java/gtk.jar HelloWorld.scala)
import org.gnome.gtk._
object HelloWorld {
  def main(args: Array[String]) {
    var hello = new InfoMessageDialog(null, "Hello world!", "This is an example dialog.")


  • Dependency: gtk3
  • Makedependency: vala
  • Build with: valac --pkg gtk+-3.0 hello_world.vala
using Gtk;
public class HelloWorld {
	static void main (string[] args) {
		Gtk.init (ref args);
		var Hello=new MessageDialog (null, Gtk.DialogFlags.MODAL, Gtk.MessageType.INFO, Gtk.ButtonsType.OK, "Hello world!");
		Hello.format_secondary_text ("This is an example dialog."); ();

Visual Basic .NET

  • Dependency: gtk-sharp-3
  • Makedependency: mono-basic
  • Build with: vbnc -r:/usr/lib/mono/gtk-sharp-3.0/gio-sharp.dll -r:/usr/lib/mono/gtk-sharp-3.0/glib-sharp.dll -r:/usr/lib/mono/gtk-sharp-3.0/gtk-sharp.dll hello_world.vb
  • Run with: mono hello_world.exe
Imports Gtk
Public Class Hello
	Inherits MessageDialog
	Public Sub New
		MyBase.New(Me, DialogFlags.Modal, MessageType.Info, ButtonsType.Ok, "Hello world!")
		Me.SecondaryText = "This is an example dialog."
	End Sub
	Public Shared Sub Main
		Dim Dialog As New Hello
	End Sub
End Class

See also