Sugar Components

This is part 2 of the Sugar internals series. Part 1 is at Understanding sugar code. Part 3 is at Activity creation internals.

Sugar Components

Here, we are in the middle of walking through a sugar shell initialization to see all of the packages and utilities used in the sugar environment. Previously, we saw how Fedora is set up to launch sugar within a python context. Sugar had python launch Matchbox as an X windows environment, and DBUS as an interprocess messaging bus. After importing serveral python libraries (sys, os, gtk, & gobject), and some sugar environment libraries (env, logger, profile, & TracebackUtils), sugar is now going to continue setting up by importing special core python libraries and instantiating various classes and routines... Let's see what happens:

Sugar Package & Module Imports

The sugar-shell has already imported python and sugar environment modules, but now, sugar starts to import component modules from the view and model packages:

>>> from view.FirstTimeDialog import FirstTimeDialog
>>> from view.Shell import Shell
>>> from model.ShellModel import ShellModel

This looks a good bit like a Model, View, Controller design pattern.

Also, here is a bit about Python Modules and Packages.

Sugar's View Package

This thing's python path is sugar.view

It includes these modules:

• ActivityHost -- For sharing activities and managing a chat for each shared activity
• BuddyIcon -- The actual buddy Icon (an object) in the neighborhood & friends window.
• BuddyMenu -- Popup menu when you point to a buddy in your neighborhood (or friends window?)
• FirstTimeDialog -- Special dialog to get your nickname. Also randomly assigns you a color.
• OverlayWindow -- something to do with window management??
• Shell -- This module pulls together several objects and manages the actuall Shell class.
• clipboardicon -- logic for one item on the clipboard.
• clipboardmenu -- manages items on clipboard and copy status.
• stylesheet -- Sets default sizes and colors for sugar UI icons.

And these sub-packages:

frame

Manages the OLPC-HIG sugar ui side frame.

• ActivitiesBox
• Frame
• FriendsBox
• PanelWindow
• ZoomBox
• clipboardbox
• clipboardpanelwindow
• notificationtray
• overlaybox

home

Manages the OLPC-HIG zoom metaphor of the sugar ui center for the Mesh, Friends, & Donut views.

• FriendView -- ? OLPC-HIG Groups
• FriendsBox -- ? OLPC-HIG Groups
• HomeBox -- ? OLPC-HIG home
• HomeWindow -- ?
• MeshBox -- ? OLPC-HIG Neighborhood
• MyIcon -- Initializes OLPC-HIG user icon color based on stored preference file.
• activitiesdonut -- Manage the activities in the process donut view.

Sugar's Shell Module

Sugar's Shell Module pulls lots of services and system interfaces together and unifies them into a full user interface. The Shell module is a part of the View package.

Imports:

• logging -- (sugar logger)
• gtk -- (The GIMP Tool Kit)
• gobject -- (gtk package)
• wnck -- (Window Navigator Construction Kit)

Lots of Sugar UI imports:

• view.stylesheet
• style
• HomeWindow
• PresenceService
• ActivityHost
• ActivityFactory
• Activity
• Frame
• ShellModel
• HardwareManager
• KeyGrabber
• AudioManager
• env
• sugar

Sugar's Model Package

The Model Packages has the following modules:

• BuddyModel -- Tracks the details and connection to a single buddy on the mesh
• Friends -- Adds and removes Buddies to a list of friends
• Invites -- Invites Buddies to shared activities.
• MeshModel -- Tracks Activities, presense, and connections
• Owner -- Tracks details about the OLPC owner (nickname, icon, etc.)
• ShellModel -- Tracks List of Activities, Presence, List of Friends, Home, also announces presence of computer to others.
• homeactivity -- This class is instantiated to control a running activity.
• homemodel -- This is the data model used to manage a running activity.