Learning WML and WMLScript

The next generation of mobile communicators is here, and delivering content to them will mean programming in WML (Wireless Markup Language) and WMLScript, the languages of the Wireless Application Environment (WAE). The WAE allows information in almost all applications to be formatted for display on mobile devices, such as cell phones, and enables the user to interact with the information. Why learn yet another technology? According to some estimates, 75 per cent of Web document viewing by the year 2002 will be through non-desktop devices, many using wireless technologies. Clearly, the future is wireless. For Web developers who want to get up to speed quickly in these languages, Learning WML & WMLScript maps out in detail the WAE and its two major components, WML and WMLScript. Fortunately, the WAE provides a World Wide Web-like model for writing applications, incorporating several key features of the Web to ease the transition for developers. Almost all wireless applications can be written with WML, which replaces HTML in the wireless environment, and WMLScript, which replaces JavaScript. With this book, Web developers with some knowledge of programming and C, Java, or JavaScript syntax can master both languages. Chapter by chapter, Learning WML & WMLScript takes readers through the following WML topics: decks, templates and cards; User Interaction; variables and contexts; tasks, events, and timers; text and text formatting; and images. WMLScript topics include: data types, conversions and variables; operators and expressions; statements; functions; and standard libraries.

Table of Contents:
Preface 1. Introduction to WML A Complete Example Cards Empty-Element Tags Elements Attributes Entities Comments 2. WML Variables and Contexts Variable Substitution Setting Variables Browser Contexts 3. WML Tasks and Events Tasks Events 4. WML User Interaction Problems with Web Interaction Interaction in WAP The Element The Element The Element The Element The Element The Element The Element The tabindex Attribute 5. WML Timers Using Timers with WML The Element 6. WML Decks, Templates, and Cards The Element The Element The Element The Element The Element The Element 7. WML Text and Text Formatting The Element The Element Character Formatting Tables 8. WML Images The Element The WBMP Image Format 9. Introduction to WMLScript WMLScript with WML What Is WMLScript? 10. WMLScript Datatypes, Variables, and Conversions Datatypes and Literals Variables Type Conversion 11. WMLScript Operators and Expressions Operand Conversions Assignment Operators Arithmetic Operators Bitwise Operators Shift Operators Logical Operators Increment and Decrement Operators Comparison Operators Type Operators The Conditional Operator The Comma Operator Precedence and Associativity 12. WMLScript Statements Expressions as Statements Blocks of Statements Conditions Loops Returning from a Function Other Statements 13. WMLScript Functions Function Declarations Function Calls Calls to Other Script Units Calling WMLScript from WML Standard Libraries 14. WMLScript Pragmas The access Pragma The meta Pragma 15. The Lang Library abort abs characterSet exit float isFloat isInt max maxInt min minInt parseFloat parseInt random seed 16. The Float Library ceil floor int maxFloat minFloat pow round sqrt 17. The String Library charAt compare elementAt elements find format insertAt isEmpty length removeAt replace replaceAt squeeze subString toString trim 18. The URL Library escapeString getBase getFragment getHost getParameters getPath getPort getQuery getReferer getScheme isValid loadString resolve unescapeString 19. The WMLBrowser Library getCurrentCard getVar go newContext prev refresh setVar 20. The Dialogs Library alert confirm prompt 21. Complete Examples Calculator Battleships A. Absolute and Relative URLs B. WAP Gateways and WSP C. Summary of WMLScript Operators D. Serving WAP Content from a Standard Web Server Index