The best way for a Swing developer to get into mobile is just to open a LWUIT based project and start working, its just that simple! At first the use of styles might seem slightly alien but you get used to it instantly and its ridiculously familiar.
There are quite a few differences between LWUIT and Swing which came thanks to the fact that we could learn and adapt from Swing. So LWUIT is in effect better than Swing mostly thanks to it being newer. Here is a list of highlight/bullet points for Swing developers wishing to take a look at LWUIT.
- Component/Container hierarchy with layout managers to arrange the elements. All the old friends are there with some additional added features (GridLayout, BorderLayout, BoxLayout, FlowLayout, GroupLayout) and some new (TableLayout, LayeredLayout). Naturally LWUIT doesn't feature the whole JComponent sub hierarchy and maintains a simpler hierarchy.
- You can override paint and get a graphics object to do whatever you want. LWUIT is lightweight (just like Swing) and draws everything on its own to maximize portability and flexibility
- You can add/remove action listener and similar observer based patterns for various events
- Dialogs can be modal, so when you use Dialog.show() or similar method the next line won't execute until the dialog is disposed. Like in Swing, this is entirely optional.
- LWUIT has a glasspane, its a bit different from the Swing glasspane but very similar in functionality
- List model and list cell renderer, pretty much like Swing's API with added functionality for animations and horizontal lists.
- ContentPane for the body of the Form (LWUIT's root component) which is technically hidden
- The LWUIT EDT requires that you interact with it over a single thread, it has a callSerially method (invokeLater), callSeriallyAndWait (invokeAndWait) and even an invokeAndBlock (foxtrot for the advanced swing users)
What's Different :
- Optimized for phones/tablets both touch & feature phones. This includes support for gestures and complex key layouts
- Styles & Themeing - the PLAF is much narrower in LWUIT (due to size constraints) but LWUIT makes up for it by having a Style object associated with every component. Furthermore, LWUIT allows customizing said styles with a theme that can be created visually using an open source resource editor tool!
- Animations are integrated in the core of LWUIT in several levels. You can animate layouts, transitions and just arbitrary objects.
- The resource file format is an integral part of LWUIT (although technically completely optional) it offers a GUI builders (optional but quite helpful), theme creator, localization etc. Unlike matisse it doesn't generate any code thus providing a more VB like experience where the UI and code are cleanly separated. The tool can be given to a designer with no coding experience
- Painters - Swing tried to integrate painters after the fact and failed since the framework needs to be designed with them to begin with. We did just that. We also separated background painting from foreground painting and made it easier to override just background painting.
- Deep and elaborate porting layer allowing LWUIT to be ported to any platform easily
- LWUIT is truly open source - while Swing was technically open sourced, debugging/modifying Swing was not trivial since it was integrated into the JDK. This also prevented developers from incorporating fixes (or a known working version) into their build.
LWUIT is bundled with the application so you can easily fix it and very easily modify code/debug to locate/fix issues. The development is easy to follow with a public viewable SVN. You can actually get commits from us as we fix issues and add features.