ne of the hardest things about developing Java ME applications, especially for Connected Limited Device Configuration (CLDC)/Mobile Information Device Profile (MIDP) apps, has been trying to figure out how to build a palatable graphical user interface. Just getting the job done is hard enough given the restrictive Limited Capability Device User Interface (LCDUI) API. Trying to build user interfaces that are engaging and “rich” is pretty close to impossible. There have always been options for building the UI, but the options usually leave developers choosing between easier-to-build/poor looking displays versus harder-to-build/better-looking displays and potential portability issues. Thus many consider the "Limited Capability" part of the LCDUI acronym an understatement. At this year's JavaOne conference (held in early May), Sun unveiled a fountain of hope for Java ME developers responsible for user interfaces.
The Lightweight UI Toolkit or LWUIT (pronounced loo-it by Jeet Kaul, Sun Vice President, Client Software Group) is a free UI library and tool for creating richer and more portable Java ME user interfaces.
According LWUIT team member Yoav Barel, "LWUIT was inspired by Swing and its design." That becomes immediately apparent when you start to work with the feature set LWUIT brings to Java ME user interfaces. LWUIT's rich set of UI components, layout management, animation and transitions, and themes should even impress graphical designers and user interface specialists.
The current version of the library works on top of CLDC/MIDP. However, Sun plans to make the library available on other Java ME platforms such as the Connected Device Configuration. If successful in making the library available on other configurations and platforms, this would make LWUIT a true cross-platform capability and help to eliminate a major source of device fragmentation issues that occur at the graphical user interface level.