XForms Essentials

The use of forms on the web is so commonplace that most user interactions involve some type of form. XForms--a combination of XML and forms--offers a powerful alternative to HTML-based forms. By providing excellent XML integration, including XML Schema, XForms allows developers to create flexible, web-based user-input forms for a wide variety of platforms, including desktop computers, handhelds, information appliances, and more.

XForms Essentials is an introduction and practical guide to the new XForms specification. Written by Micah Dubinko, a member of the W3C XForms working group and an editor of the specification, the book explains the how and why of XForms, showing readers how to take advantage of them without having to write their own code. You'll learn how to integrate XForms with both HTML and XML vocabularies, and how XForms can simplify the connection between client-based user input and server-based processing.

XForms Essentials begins with a general introduction to web forms, including information on history and basic construction of forms. The second part of the book serves as a reference manual to the XForms specification. The third section offers additional hints, guidelines, and techniques for working with XForms. Topics covered in the book include:

• creating XForms files in a text or XML editor
  
• converting existing forms (electronic or paper) to XForms
  
• collecting XML data from users in a user-friendly way
  
• reducing the amount of JavaScript needed within browser interfaces
  
• increasing the security and reliability of your current forms system by combining client-side and server-side checks into a common code base
  
• creating interactive websites using the latest standard technology

XForms Essentials focuses on the practical application of XForms technology. If you work with forms, HTML, or XML information, XForms Essentials will provide you with a much simpler route to more sophisticated interactions with users.

Table of Contents

Preface 

1. Introduction to Web Forms

      The Past, Present, and Future of Web Forms 

      A Brief Review of HTML Forms 

      Limitations of HTML Forms, Advantages of XForms 

      The History of XForms 

      The Revenge of the Simple Syntax 

2. XForms Building Blocks

      More Than Forms 

      A Real-World Example 

      Host Language Issues 

      Linking Attributes 

3. XPath in XForms

      Getting Up to Speed with XPath 

      Going Deep: The XPath Data Model 

      Location Paths 

      Computed Expressions 

      How XPath is Used in XForms 

4. XML Schema in XForms

      Wide Open (Value) Spaces 

      Useful Datatypes 

      Other Datatypes 

      An Email Datatype for XForms 

      Complex Types 

      xsi:type 

5. The XForms Model

      Will the Real Data Model Step Forward? 

      Structural Elements 

      Common Attributes 

      Model Item Properties 

      Making the Connection-Binding 

6. The XForms User Interface

      Form Controls 

      Interaction with Instance Data 

      Grouping 

      Dynamic Presentation 

      Repeating Line Items 

7. Actions and Events

      XML Events 

      XForms Actions 

      XForms Events 

8. Submit

      When to Submit 

      What to Submit 

      Where and How to Submit 

      What Happens After Submit? 

      The submission Element 

      Review: Submission Options 

      Security and Privacy Concerns 

9. Styling XForms

      CSS, Level 3 

10. Form Accessibility, Design, and Troubleshooting

      Basics of Accessibility 

      Form Design Patterns 

      XForms-specific Design Hints 

      Troubleshooting 

      Making the Switch to XForms 

11. Extending XForms

      The Cost of Extensibility 

      Ways to Extend 

A. Examining Microsoft InfoPath

B. The GNU Free Documentation License

Index