C H A P T E R 1

Overview

The Java Wireless Client software is an implementation of the MIDP 2.1 Specification that provides handset manufacturers and graphical user interface developers the tools to create graphical presentations on a wide range of mobile devices. It does this by providing Adaptive User Interface Technology (AUIT), which is a set of predefined graphical elements that can be customized to create a distinct look and feel. By customizing the AUIT, it becomes possible to present high-level graphic elements that closely match the native presentation on a device.

Adaptive User Interface Default Skin

The Java Wireless Client software comes with a default set of AUIT components, also known as a default "skin." The default skin is one example of how the adaptive user interface can be presented on a mobile device. Customers porting the Java Wireless Client software can use the default skin in their implementations or they can customize it for their own look and feel. This guide provides the directions you need to customize Java Wireless Client software adaptive user interface skins for your devices.

The Java Wireless Client software adaptive user interface accommodates a wide range of user experience models on devices ranging from small grayscale screens to large color displays. The default skin includes bright, saturated colors for a device. On linux_fb and linux_qte platforms, the supported resolution is 176x210 pixels. On a win32_javcall platform, the supported resolution is 240x320 pixels. Both target the consumer demographic. The adaptive user interface also supports features such as layering, translucency, animation, and portable skins.

Note - This document does not provide instructions for porting Adaptive User Interface Technology or its components. For information on how to port adaptive user interfaces, see the Sun Java Wireless Client Porting Guide.

Understanding the Default Skin

The Java Wireless Client software implementation provides a default adaptive user interface look and feel, which is the default skin. This guide uses the default skin as an example to explain the following adaptive user interface topics:

The graphical elements used in the adaptive user interface, for example, a soft button, a system menu, a ticker, or a progress bar.

The customizable skin file, skin.xml, that contains the property settings and values used by the default skin, in XML format. It describes how to modify this default skin file to create your own unique adaptive user interface look and feel.

The reference skin file, skin_constants.xml, that contains all the possible property settings used by each graphical element, presented in an XML format.

The actions you take before customizing the default skin, such as considering you design elements and preparing your graphic images.

The actions you take to modify and redisplay your customized skin, as you develop it for your implementation.

Using the Optional Second Skin

The Java Wireless Client software provides an optional second skin that can be used as a visual sanity check and reference tool by the visual designer during the process of customizing your own skin.

This optional second skin makes it possible for the visual designer to compare how different image files, with the same file names and settings assigned in the skin.xml file, can produce different appearances in the default skin when it is displayed in the Java Wireless Client emulator during the development process. This makes it easy for the visual designer to see how changing specific elements of the skin can affect the look of the skin, without actually changing the skin itself.

For more information about the optional second default skin, see Chapter 2.

Overview of the Adaptive User Interface Process

The Java Wireless Client software adaptive user interface default skin can be used as is, without any additional customization. However, to change the look and feel of the default skin, you can customize it by following these general steps:

1. Evaluate the design issues you need to address for your implementation:

Types and number of devices to run your customized skin

Desired color scheme

Kind of background images you want to display

Other issues need to be considered as well. For more information on design considerations, see Chapter 2.

2. Evaluate, create, and assemble the graphic images to use in your customized skin. For example, you might want to present a different background image than the default skin. To do this, you must create the image files required to construct and tile these backgrounds.

For more information on working with graphic images, see Chapter 2.

Note - Properly preparing graphic images for your customized skin requires the skills of a visual designer, using specialized tools. Detailed instructions for preparing your graphics are outside the scope of this document.

3. Customize the default property file, skin.xml, by redefining the value assignments for each graphical element used in your customized skin.

The skin.xml file is customized separately for each platform you are supporting. For example, the Java Wireless Client software provides a skin.xml file for the following supported platforms, including the JavaCall trademark API: linux_fb, linux_qte, and win32_javacall. To customize the default skin for these platforms, you must customize the skin.xml file individually for each one.

For more information on customizing the default skin property file, see Chapter 3.

4. Refer to the skin reference file, skin_constants.xml. This file contains complete descriptions of the visual design elements, the property settings, the type assignments, and the purpose of each graphical component in the adaptive user interface.

You do not change this file. Only one skin_constants.xml file is provided and it is for reference only. It is recommended that you become familiar with it before you customize your skin and use it for reference during the skin update process.

For more information on the skin reference file, see Chapter 4.

5. Build your customized skin. This is done initially as part of the Java Wireless Client software build process. Once the default skin is built, it is possible to modify and customize the skin in two ways:

Make modifications to property settings in the skin.xml file. This enables you to change items such as background color, text descriptions, and other settings that do not require changes to graphic image content.

Make modifications to existing graphic image files or add new graphic files.

For step-by-step instructions on how to customizing your skin, see Chapter 5. For information on how to regenerate or build your newly customized skin, see Chapter 6.

When to Customize

The Java Wireless Client software adaptive user interface default skin can be customized for your own look and feel at the following times:

Before you port the Java Wireless Client software to your implementation. For information on customizing the default skin as part of the porting process, see the Sun Java Wireless Client Porting Guide.

After you complete your port, following a process of customization, until you achieve the look, feel, and performance you are seeking.

The steps for customizing the default skin are contained in this guide. For information on building a Java Wireless Client software implementation that includes your customized skin, see the Sun Java Wireless Client Build Guide.