• Start Here!
• Preparing for Development
• Installing Image Creator
• Projects and Targets
• Creating a Target Image
• Development System
• Development Guides
• Sample Code
• Moblin Compliance
• Reference Documentation
• FAQ
• Glossary

Concept
After creating a target using Moblin Image Creator, you can add one or more fsets to the target. A an fset is a bundle of individual packages that add a certain high level of functionality. Some are specifically aimed for development, system configuration, or localization. Some fsets may depend on other fsets. If you choose to install a an fset with dependencies, Moblin Image Creator will automatically install its dependent fsets.

Functional Set Configuration
When using Moblin Image Creator to build images, there are different platform architectures you may select among, based on the physical architecture of your device. For example, the Samsung Q1 Ultra* is currently being built with the McCaslin Low Power Intel Architecture (LPIA). If you select the platform mccaslin-lpia, Moblin Image Creator will allow you to install only the fsets specific to that platform. Some fsets are available to all architectures and some are specific to particular devices.

For each platform, there is detailed information describing the available fsets in the fset configuration file. By reading the file specific to your platform, you can add fsets according to your need. These files can usually be found at /usr/share/pdk/platforms/[chosen-platform]/fsets/base.fset on your workstation. For example, if your target platform is menlow-lpia, the fset configuration file would be located at /usr/share/pdk/platforms/menlow-lpia/fsets/base.fset.

Basic Functional Sets
Certain fsets are commonly used, either because they contain the most fundamental packages or they contain a wide variety of packages covering most users' needs. Other fsets are important, because they provide a very specific functionality. The following sections describe the content of these fsets.

Hildon Libraries
Hildon, the GUI application framework of Maemo*, is based on GTK+, and some other technologies from the GNOME framework. Hildon contains some enhancements to GTK+, making it more suitable for the use on mobile devices. A more detailed description of Hildon can be found here.

Moblin also uses Hildon as an application framework. Here are three major Hildon libraries that you may need to install for Moblin application development:

• libhildon: This library contains is the widgets collection that can be used by Moblin applications. It provides an enhancement on the standard GTK+ widgets that enables specific mobile functionality and provides richer graphics. This will automatically get installed when adding the fset Developer-Tools.
• libhildondesktop: This library is the desktop environment for hand-held devices. Features it provides include task navigation, status bar items (such as showing battery/wireless information), and system menu, etc. In Moblin, both "Home" and "Marquee" are developed based on libhildondesktop. This will automatically get installed when adding the fset Developer-Tools.
• libhildonfm: This library is the Hildon File Management and is based on GNOME VFS. It provides a unified management mechanism to local and remote/internet file management. The Hildon File Management library includes a bunch of easy-to-use, built-in objects, such as standard Hildon file selection/chooser dialog, file container widget, and the ability to query file information and attributes.

GStreamer* Libraries
GStreamer is a framework for creating streaming media applications. The framework is designed to make it easy to write applications ranging from simple Ogg/Vorbis playback to complex audio (mixing) and video (non-linear editing) processing.

One of the most obvious uses of GStreamer is media player. GStreamer already includes components for building a media player that can support a very wide variety of formats. Developers can also add new codecs and filters by writing a simple plug-in with a clean, generic interface^[1].

More documents can be found at http://gstreamer.freedesktop.org/. You can download the GStreamer packages from this website. Also, you can use apt or yum to install GStreamer. For example, when using apt to install Gstreamer Core development files, you can run apt-get install libgstreamer0.10-dev.

Helix* Libraries
Helix* is very similar to GStreamer, which is also a multimedia framework to handle video and audio coding, synchronizing, and other processes. It is cross-platform (Symbian*, Linux*, Windows*, Solaris*, Mac*, etc.), and is sponsored by Real Network Corp. It has many success models (such as media players) on handset devices. Comparing with GStreamer, Helix supports DRM (Digital Rights Management)^[2]. More detailed information can be found at http://helixcommunity.org/.

To set up a Helix engine on a Moblin target file-system for development, you can follow the instructions in this document.

D-Bus Related Libraries
D-Bus is a message bus system, that is, a simple way for applications to talk to one another. In addition to interprocess communication, D-Bus helps coordinate the process lifecycle; it makes it simple and reliable to code a "single instance" application or daemon, and to launch applications and daemons on demand when their services are needed^[3]. More detailed information can be found at http://www.freedesktop.org/wiki/Software/dbus.

LibOSSO, a wrapper of the D-Bus's low level APIs, is a library all applications designed for Maemo are expected to use. It provides a notification mechanism to applications so they can close gracefully in the event of system shut down or low memory. In addition, LibOSSO conveniently isolates the application from possible implementation changes on D-Bus level.

LibOSSO also provides useful utility functions to handle autosaving and state saving features of the platform, process hardware state and device mode changes and other important events happening in Internet Tablets. It also provides convenient utility wrapper functions to send remote procedure method calls over the D-Bus^[4]. You can refer to http://maemo.org/maemo_training_material/maemo4.x/html/maemo_Platform_Development/
Chapter_02_LibOSSO.html for more detailed information about LibOSSO.

You can use apt or yum to install D-Bus related development files. For example, when using apt to install LibOSSO development files, you can run apt-get install libosso-dev.