Beyond Linux® From Scratch (systemd Edition) - Version 11.3

Chapter 25. Graphical Environment Libraries

GTK+-3.24.36

Introduction to GTK+ 3

The GTK+ 3 package contains libraries used for creating graphical user interfaces for applications.

This package is known to build and work properly using an LFS 11.3 platform.

Package Information

GTK+ 3 Dependencies

Required

at-spi2-core-2.46.0, gdk-pixbuf-2.42.10, libepoxy-1.5.10, and Pango-1.50.12

Recommended

adwaita-icon-theme-43 (default for some gtk+3 settings keys, also needed for tests), docbook-xsl-nons-1.79.2 (for generating manual pages), hicolor-icon-theme-0.17 (needed for tests), ISO Codes-4.12.0, libxkbcommon-1.5.0, libxslt-1.1.37 (for generating manual pages), sassc-3.6.2, Wayland-1.21.0, and wayland-protocols-1.31

Recommended (Required if building GNOME)

gobject-introspection-1.74.0

Optional

colord-1.4.6, Cups-2.4.2, GTK-Doc-1.33.2, PyAtSpi2-2.46.0 (for tests), Tracker-3.4.2, and PAPI

User Notes: https://wiki.linuxfromscratch.org/blfs/wiki/gtk3

Installation of GTK+ 3

Install GTK+ 3 by running the following commands: 

mkdir build &&
cd    build &&
meson setup --prefix=/usr           \
            --buildtype=release     \
            -Dman=true              \
            -Dbroadway_backend=true \
            .. &&
ninja

To test the results you need a graphical session, then issue ninja test. Two tests may fail because the time out setting is too short.

Now, as the root user: 

ninja install
[Note]

Note

If you installed the package on to your system using a “DESTDIR” method, an important file was not installed and must be copied and/or generated. Generate it using the following command as the root user: 

gtk-query-immodules-3.0 --update-cache
[Note]

Note

If you installed the package to your system using a “DESTDIR” method, /usr/share/glib-2.0/schemas/gschemas.compiled was not updated/created. Create (or update) the file using the following command as the root user: 

glib-compile-schemas /usr/share/glib-2.0/schemas

Command Explanations

-Dbroadway_backend=true: This switch enables the HTML5 GTK backend.

-Dman=true: This switch allows generating manual pages.

-Dgtk_doc=true: This switch enables building documentation. It requires GTK-Doc-1.33.2.

-Dtracker3=true: This switch enables the search function based on Tracker 3 in the GTK+-3 file chooser dialog. It requires Tracker-3.4.2.

Configuring GTK+ 3

Config Files

~/.config/gtk-3.0/settings.ini and /etc/gtk-3.0/settings.ini

Configuration Information

GTK+ 3 themes change the way a GTK+ 3 application looks. An icon theme can be used to change the icons that appear on the application's toolbar. If you have installed a GTK+ 3 theme (e.g. the Adwaita theme built in GTK+ 3), an icon theme (such as oxygen-icons5-5.103.0) and/or a font (Dejavu fonts), you can set your preferences in ~/.config/gtk-3.0/settings.ini, or the default system wide configuration file (as the root user), in /etc/gtk-3.0/settings.ini. For the local user an example is: 

mkdir -vp ~/.config/gtk-3.0
cat > ~/.config/gtk-3.0/settings.ini << "EOF"
[Settings]
gtk-theme-name = Adwaita
gtk-icon-theme-name = oxygen
gtk-font-name = DejaVu Sans 12
gtk-cursor-theme-size = 18
gtk-toolbar-style = GTK_TOOLBAR_BOTH_HORIZ
gtk-xft-antialias = 1
gtk-xft-hinting = 1
gtk-xft-hintstyle = hintslight
gtk-xft-rgba = rgb
gtk-cursor-theme-name = Adwaita
EOF

There are many settings keys, some with default values. You can find them at Settings: GTK+ 3 Reference Manual. There are many more themes available at https://www.gnome-look.org/browse/ and other places.

As part of GTK+-3.0's redesign, the scroll bar buttons are no longer visible on the scrollbar in many applications. If this functionality is desired, modify the gtk.css file and restore them using the following command: 

cat > ~/.config/gtk-3.0/gtk.css << "EOF"
*  {
   -GtkScrollbar-has-backward-stepper: 1;
   -GtkScrollbar-has-forward-stepper: 1;
}
EOF

Contents

Installed Programs: broadwayd, gtk3-demo, gtk3-demo-application, gtk3-icon-browser, gtk3-widget-factory, gtk-builder-tool, gtk-encode-symbolic-svg, gtk-launch, gtk-query-immodules-3.0, gtk-query-settings, and gtk-update-icon-cache
Installed Libraries: libgailutil-3.so, libgdk-3.so, and libgtk-3.so
Installed Directories: /etc/gtk-3.0, /usr/include/{gail,gtk}-3.0, /usr/{lib,share}/gtk-3.0, and /usr/share/themes/{Default,Emacs}/gtk-3.0

Short Descriptions

broadwayd

provides support for displaying GTK+ 3 applications in a web browser, using HTML5 and web sockets

gtk3-demo

is a simple program that demonstrates some of the tasks that can be done with GTK+ 3

gtk3-demo-application

is a simple GTK+ 3 application

gtk3-icon-browser

is a utility to explore the icons in the current icon theme. It shows icons in various sizes, their symbolic variants where available, as well as a description of the icon and its context

gtk3-widget-factory

is a program to view GTK+ 3 themes and widgets

gtk-builder-tool

performs various operations on GtkBuilder .ui files

gtk-encode-symbolic-svg

converts symbolic SVG icons into specially prepared PNG files. GTK+ 3 can load and recolor these PNGs, just like original SVGs, but loading them is much faster

gtk-launch

launches an application using the given name. The name should match the application desktop file name, as residing in /usr/share/applications, with or without the '.desktop' suffix

gtk-query-immodules-3.0

collects information about loadable input method modules for GTK+ 3 and writes it to the default cache file location, or to standard output

gtk-query-settings

provides a complete listing of all settings related to GTK+ 3

gtk-update-icon-cache

is an icon theme caching utility that creates mmap()able cache files for icon themes

libgailutil-3.so

contains functions that implement the accessibility interfaces defined by the GNOME Accessibility Toolkit

libgdk-3.so

contains functions that act as a wrapper around the low-level drawing and windowing functions provided by the underlying graphics system

libgtk-3.so

contains functions that provide an API to implement graphical user interfaces