GTK+

Name	GTK+
Logo
Developer	GNOME Foundation
Latest release version	3.0.11
Latest release date
Latest preview version	3.1.6
Latest preview date
Programming language	C
Operating system	Cross-platform
Platform	Cross-platform
Size	18 MB
Language	Multilingual
Status	Active
Genre	Widget toolkit
License	GNU Lesser General Public License
Website	http://www.gtk.org/

GTK+ (GIMP Toolkit) is a cross-platform widget toolkit for creating graphical user interfaces. It is one of the most popular toolkits for the X Window System, along with Qt.

GTK+ was initially created for the GNU Image Manipulation Program (GIMP), a raster graphics editor, in 1997 by Spencer Kimball and Peter Mattis, members of eXperimental Computing Facility (XCF) at University of California, Berkeley.

GTK+ is licensed under the terms of the LGPL free software license, which allows both free and proprietary software to use it. GTK+ is part of the GNU Project, which aims to create a whole free software operating system (the LGPL was originally written for the GNU Project).

Design

GTK+ is an object-oriented widget toolkit written in the C programming language; object-orientation is achieved by using the GLib object system. On the X11 display server, GTK+ uses Xlib to draw widgets. Using Xlib provides flexibility and allows GTK+ to be used on platforms where the X Window System is unavailable. While GTK+ is primarily targeted at the X Window System, other platforms are supported, including Microsoft Windows, and Quartz on Mac OS X. HTML5 and Wayland backends are in development.

GTK+ can be configured to change the look of the widgets drawn; this is done using different display engines. Several display engines exist which try to emulate the look of the native widgets on the platform in use.

Programming language bindings

A library written in one programming language may be used in another programming language if bindings are written; GTK+ has bindings in many languages.

See the table below:

{| class="wikitable sortable" ! Language ! Name ! Support |- ! Ada | GtkAda | style="text-align:center;" | Partial support up to 2.18 |- ! C | GTK+ | |- ! C++ | gtkmm | |- !C# and other .NET languages | Gtk# | style="text-align:center;" | Partial support up to 2.20 |- ! D | gtkD | style="text-align:center;" | Partial support up to 2.20 (plus Cairo, Gda, Gl, GStreamer) |- ! Erlang | gtkNode | style="text-align:center;" | Partial support up to 2.16 |- !GOB | languages written for the GObject system. | |- !Gambas | gambas2-gb-gtk | |- !Genie | languages written for the GObject system. | |- ! Haskell | gtk2hs | |- ! Fortran | gtk-fortran | style="text-align:center;" | Partial support up to 2.24 & 3.0 |- ! FreeBASIC | GladeToBac | style="text-align:center;" | Supports all versions from 2.8 to 3.0 |- ! FreePascal | (header) integrated into the core distribution | style="text-align:center;" | GTK 2.16 with partial support of later versions

|- ! Java | java-gnome | style="text-align:center;" | Partial support up to 2.20 (not available on Windows) |- ! JavaScript | seed/GJS | |- ! Lua | lgob | style="text-align:center;" | Supports all versions from 2.16 |- ! Lua | LuaGtk | style="text-align:center;" | Partial support up to 2.16 |- ! Ocaml | LablGTK | style="text-align:center;" | Partial support up to 2.16 |- ! Perl | Gtk2-Perl | style="text-align:center;" | Partial support up to 2.20 |- ! PHP | PHP-GTK | style="text-align:center;" | Partial support up to 2.20 |- ! Python | PyGTK | |- ! R | RGtk2 | style="text-align:center;" | Partial support up to 2.12 |- ! Ruby | ruby-gtk2 | |- ! Smalltalk | Smalltalk GTK | style="text-align:center;" | GNU Smalltalk, Smalltalk YX, Squeak |- ! Tcl | Gnocl | |- ! Vala | languages written for the GObject system. | |}

History

GTK+ was originally designed and used in the GNU Image Manipulation Program (GIMP) as a replacement of the Motif toolkit; at some point Peter Mattis became disenchanted with Motif and began to write his own GUI toolkit called the GIMP toolkit and had successfully replaced Motif by the 0.60 release of GIMP. Finally GTK was re-written to be object oriented and was renamed GTK+. This was first used in the 0.99 release of GIMP.

GTK+ 2 has succeeded GTK+. Its new features include improved text rendering using Pango, a new theme engine, improved accessibility using the Accessibility Toolkit, complete transition to Unicode using UTF-8 strings, and a more flexible API. However, GTK+ 2 lacks compatibility with GTK+ 1, and programmers must port applications to it.

Starting with version 2.8, GTK+ 2 depends on the cairo graphics library for rendering vector graphics in GTK+ 2.

Future developments

Project Ridley is an attempt to consolidate several libraries that are currently external to GTK+, including libgnome, libgnomeui, libgnomeprint22, libgnomeprintui22, libglade, libgnomecanvas, libegg, libeel, gtkglext and libsexy.

Developers are also considering new directions for the library, including removing deprecated API components and adding an integrated scene graph system, similar to the Clutter graphics library, effectively integrating GTK+ with OpenGL.

Development and design of the GTK+ 3 release of the toolkit started in February 2009 during the GTK+ Theming Hackfest held in Dublin. A first draft of the development roadmap has been released on April 9, 2009.

GTK+ hello world

GTK+ hello world in the C programming language. This program has a window with the title "Hello World" and a label with similar text.

#include

int main (int argc, char *argv[]) { GtkWidget *window; GtkWidget *label;

gtk_init (&argc;, &argv;);

/* create the main, top level, window */ window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

/* give it the title */ gtk_window_set_title (GTK_WINDOW (window), "Hello World");

/* Connect the destroy signal of the window to gtk_main_quit * When the window is about to be destroyed we get a notification and * stop the main GTK+ loop */ g_signal_connect (window, "destroy", G_CALLBACK (gtk_main_quit), NULL);

/* Create the "Hello, World" label */ label = gtk_label_new ("Hello, World");

/* and insert it into the main window */ gtk_container_add (GTK_CONTAINER (window), label);

/* make sure that everything, window and label, are visible */ gtk_widget_show_all (window);

/* start the main loop, and let it rest there until the application is closed */ gtk_main ();

return 0; }

Compile: $ clang file.c $(pkg-config --cflags --libs gtk+-3.0)

Uses

2.4. GTK+ is responsible for managing the interface components of the program, including the menus, buttons, and input fields.]]

; Environments that use GTK+

GNOME is based on GTK+, meaning that GNOME programs use GTK+

Xfce is based on GTK+, though its applications typically do not depend on as many libraries (this is the difference between something being branded as a "GNOME program" or as a "GTK+ program")

LXDE (Lightweight X11 Desktop Environment) is based on GTK+

ROX Desktop is a lightweight desktop, with features from the GUI of RISC OS

GPE Palmtop Environment

Access Linux Platform (successor of the Palm OS PDA platform)

Sugar the learning platform uses GTK+ and PyGTK

KDE, though based on Qt, has integration with GTK+-based programs and themes (since version 4.2).

Those desktop environments are not required to run GTK+ programs. If the required libraries are installed, a GTK+ program can run on top of other X11-based desktop environments or window managers; this includes Mac OS X if X11.app is installed (which is the default since the Leopard release). GTK+ can also run under Microsoft Windows, where it is used by some popular cross-platform applications like Pidgin and GIMP. wxWidgets, a cross-platform GUI toolkit, uses GTK+ for Unix systems. Other ports include DirectFB (used by the Debian installer, for example) and ncurses.

; Window managers The following window managers use GTK+

Aewm

AfterStep

Amaterus

Fluxbox

IceWM

Metacity

Mutter

Sawfish

Wmg

Xfwm

Applications

Some notable applications that use GTK+ as a widget toolkit include:

AbiWord – Word processor

Anjuta – open-source IDE

Ardour – Digital Audio Workstation

Chromium – Web browser based upon WebKit and developed in large part by Google

Ekiga (formerly GnomeMeeting) – VoIP and video conferencing application

Epiphany - Official GNOME Web browser.

Evolution – personal information manager

GIMP – Raster graphics editor

Gnumeric – Spreadsheet software

GRAMPS – Genealogy software

Gretl – Econometrics package

Inkscape – SVG Vector graphics editor

Midori – lightweight web browser

MonoDevelop – open-source IDE

Pidgin – Instant messaging

Surf - lightweight WebKit-based web browser

VMware Player – virtualization software

Wireshark – packet analyzer

Licensing

GTK+ is released under the GNU Lesser General Public License version 2.1. According to the GTK+ Project world-wide website:

See also

gtkmm – C++ bindings for GTK+

FLTK – A light, cross-platform, non-native widget toolkit

FOX toolkit – A fast, open source, cross-platform widget toolkit

Microsoft Foundation Class Library (MFC)

Object Windows Library (OWL)

Qt

Ultimate++

Visual Component Library (VCL)

wxWidgets - cross platform open source C++ widgets toolkit developed by community

Widget toolkit

List of widget toolkits

References

Bibliography

External links

Official website

Official GTK+ 2.x Tutorial

GTK+ Reference Manual

List of GTK+ applications

Another list of GTK+ applications

Category:Application programming interfaces Category:C libraries Category:Cross-platform software Category:Free development toolkits and libraries Category:Free software programmed in C Category:GNU Project software Category:Widget toolkits Category:X-based libraries