Large number of gnome libraries.

GTK+

• windows
• widgets
• tree & list widgets
• model/view architecture
• containers contain children
• GtkVBox - vertical stacking
• scroll bars
• some widgets know how to display scroll bars themselves
• other widgets require parent to display scroll bars
• look at GTK demo code.

GLADE

• glade - user tool that writes XML file
• Libglade - constructs user interface from XML file
• designing user interfaces
• (non?) use of glade makes it harder for others to contribute

Pango

• internationalisation
• GtkTextView widget

GtkTextView

• can’t do top to bottom text rendering, e.g. for Japanese
• all GTK text is parsed as UTF8
• mark up text in different fonts and colours

glib

• constants and macros, byte ordering, printf format specifiers
• lists, hash tables, trees, memory management, caching
• string functions, with Unicode support
• filesystem and process support
• for writing portable code, especially Win32.
• thread support
• asynchronous queues
• main loop
  • idle moments
  • scheduled basis (with timeouts)
  • when input arrives or output ready to be sent (polling/file descriptors).
  • not all external libraries fit into this, e.g. libcurl, python(?).
• very well documented

GObject

• object orientated C programming
• latest rewrite (2-4 years ago)
• call back functions
• signals
• reference counting
• boxed data types - opaque data objects
• enums, have description
• signals
  • GTK widgets
  • handlers can be changed
  • event based programming
  • call-backs
• language bindings
• descriptions
• internal objects, keep as structures, as GObjects have overhead

GConf

• shared daemon for storing configuration/preferences information
• “registry link structure”
• Havoc Pennington’s paper from OLS 2002
• designed to store parameters for running programs, system administrator friendly
• system administrator can make certain settings read-only
• requirement to store persistence state data:
  • gnome-config not safe if user logged in multiple times and running multiple copies of application
  • XML based files
• split: programmer API, back-end
• back-end: XML file, Berkeley db, networks, central machine, LDAP
• dbus?? dbus way below gnome, heavily under development
  • apt-cache show dbus-1: […] D-BUS is a message bus, used for sending messages between applications. Conceptually, it fits somewhere in between raw sockets and CORBA in terms of complexity. […]

Bonobo

• reusable composable components
• GNOME - GNU Network Object Modelling Environment
• layer on top of CORBA
• please give me any component that can give me a text field
• what is a component?
• component for E-Mail
• Widget for E-Mail, not entire application.
• self contained piece of code that serves some function and has a clearly defined interface
• Bonobo, endangered species of monkey
• factory management and object creation
• Bonobo activation: Do you have anything on the system that meets the text 1.0 interface?
• Do you have something the the text interface and the icon interface and can display PDFs?

libbonoboui

• is easy to start spelling libbonoboui but hard to know when to stop
• GEdit, example
  • spell checker
  • calendar
  • syntax highlighter
• menu items

libgnome

• support infrastructure
• initialisation, parse parameters
• help support
• high score handling for games
• displaying URLs in configured applications
• process management support (should go in glib???)
• not compulsory
• use it unless you have a good reason not to
• gnome_program_init() gnome_program_run()

libgnomeui

• extra widgets not available in GTK+
• back-ends for accessing filesystem
• more as much as possible to GTK+
• same things have to stay here, due to dependency issues
• some stuff should be removed
• library reaching the end of its life
• guaranteed not to remove any of Gnome before Gnome 3.

libgnomevfs

• yet another VFS system
• abstract open file, read file, close file, etc
• HTTP WebDAV samba ftp
• authentication stuff, single login/authentication
• MIME detection, determine correct application
• where is the desktop? Where is the trashcan?
• dynamic shared library for extra protocols, e.g. cryptographic file system
• how heavy weight is this interface

multimedia support (GStreamer)

• multimedia framework
• plug them together
• sinks, sources, pipeline, branch, merge
• 1 pipeline audio
• 1 pipeline video
• many different formats available
• writing new modules is not too difficult
• learning curve
• 13:45 Thursday, Steve Baker talks about GStreamer

libxml

• XML support
• used by Gnumeric, yelp, libbonobo
• libxslt for XSLT processing
• no dependencies on anything else in Gnome stack
• extremely well tested
• some schema support (schema large and complicated)
• relax NG, simpler then schema

printing

• separate application and user interface
• libgnomeprint application level support
• libgnomeprintui interface portions
• future looks good with Cairo support in the pipeline
• currently maintained by maintainer of Gnumeric
• previous maintainer passed away
• used by Gnumeric, Planner, Evolution.

vte

• terminal widget, zvte gnome 1. gnome-terminal uses it.

gtksourceview

• source code highlight plug-in, used in GEdit
• comes with examples

libwmck

• common window manager utility functions
• author had too much free time
• how do you get a list of all the windows the window manager knows about?
• how do you minimise/maximise windows?

panel applets

• libpanelapplet

notification area icons

• Gaim
• rythmbox
• egg tray
• libegg
• new gnome functions hatch out of libegg
• libegg, never should be used, cut & paste instead
• contains old/rotten eggs that need to be thrown out

language over then C support

libbonobo not ported to Windows

• => libgnome not ported
• => libgnomeui not ported
• => Gnumeric and planner not ported

libgnomecanvas

• recommended

libfoocanvas

• highly optimised

GDK lives under GTK, geometry, etc. gdkpixbuf high level widget

GDK-X11 lives under GDK

Audience Comment:

• “Java is so self contained in its own world, its hard to link against C libraries”

Stock icons

Human interface guidelines

Hebrew - OK button goes last place you are going to look; errr… after the last place you will have looked at

translating 100,000 strings. 8 months to translate everything

LANG= environment variable used by C library
GDM_LANG= environment variable used by GDM????

keyboard accelerators didn’t work in Arabic; underlining characters can change the meaning of certain letters.

Chinese, save menu item is only a couple of characters, keep a Roman character so accelerators remain accelerators.