The Enlightened Widget Library

Introduction

The Enlightened Widget Library (Ewl) is a high level toolkit providing all of the widgets you'll need to create your application. Ewl is built on the Enlightenment Foundataion Libraries and makes heavy use of the provided technologies. The goal of Ewl is to abstract the use of these backends and to present an easy to use object model to the end programmer. The expansive object oriented style API provides tools to easily extend widgets and containers for new situations.

Overall, Ewl is similar in design and functionality to other common toolkits such as GTK+ and QT. The APIs differ, but the overall concepts and ideas are similar. If you are familiar with these other toolkits getting into Ewl should be relatively simple.

Inheritance is used extensively throughout Ewl to reduce code duplication and simplify the programming API. Any functions that operate on a an inherited class will also operate on the inheriting class. This can be seen in the Ewl_Entry and Ewl_Text case. An Ewl_Entry inherits from Ewl_Text so a lot of the operations you'll use to set text colors and font information are the ewl_text_* class.

Features

Among the wide variety of features Ewl provides are:

Object, widget and container abstraction layers;
A variety of containers for laying out widgets in arrangements such as boxes, tables and lists;
Simple widgets such as buttons, labels, images and progressbars;
Decorative containers for wrapping borders and controls around widgets;
High level data abstractions including lists, expandable trees and combo boxes;
An extraordinarily flexible theming system;
High level abstractions to build applications quickly, such as file and color dialogs, as well as a menu system;
A flexible event system to allow application programmers to hook into nearly every change that occurs;
ewl_test: a tutorial and testing application.

Installation

As was mentioned Ewl depends on a few of the EFL libraries for its functionality. These libraries include:

Evas
Ecore
Edje
Efreet
Epsilon (optional)
Emotion (optional)
Tango (The Tango icon set is used by Ewl. If it isn't installed Ewl will still work, you just won't see any icons displayed.)

Ewl has been setup to use, if available, OpenGL, framebuffer or software X11 support in Evas. You only require one of these engines to function but can have all of them compiled in, if desired.

Note:: The framebuffer and OpenGL engines have had a lot less testing then the software engine, so your mileage may vary in their usage. About 90% of the code in the OpenGL engine is shared with the software engine so it should be pretty stable.

Once you have the pre-requisites installed you can install Ewl. This is done with your standard set of procedures:

  ./autogen.sh    (if you've checked out from cvs)
  ./configure
  make
  make install    (as root)

You can check that everything is working correctly by running:

 ewl_test

Next Steps

You should now have a working installation of Ewl available to you. So, where do you go from here? Well, a good place to start is the Getting Started pages. They will guide you through creating a simple application with Ewl.

Once you've got the basics down you can take a look at some of the more advanced topics:

Resources

There are several resources scattered around that can help you on the road to learning Ewl:

http://wiki.enlightenment.org/index.php/EWL -- Enlightenment Wiki
http://docs.enlightenment.org/api/ewl/html -- Ewl Doxygen API reference