ilixi is an application framework written in C++ with embedded Linux systems in mind. So it is important that you are familiar with both C++ and Linux.
ilixi has a very small footprint and unlike most frameworks it was specifically written to work with DirectFB from day one. This helps it achieve optimal performance in most cases.
ilixi depends on a few other libraries; these are shown in the block diagram (actual number of required libraries depends on whether you are running single or multiple applications). CPU load will be much lower if hardware acceleration is available via an up-to-date DirectFB GFX driver for your platform.
First get yourself a copy of ilixi. Click here for download instructions.
Build and install ilixi on your platform. Click here for install instructions for Ubuntu.
A good place to start learning more about usage is example code in applications folder. You will notice that classes and methods in ilixi are intuitively named so it is easy to use for first-time developers. Some are just wrappers for low-level DirectFB methods while others provide new features like Widget class which provides common functionality for all UI elements. You can learn more by going through our articles or API Reference.
If you wish to create a new project you can use this autoconf based template.