The Freedom to Achieve

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The Freedom to Achieve
Independent, Open Solutions for Business and
Government www.platinumsolutions.com
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Forming Good HabitsA Gentle Introduction To
XForms The Future Of Forms On The Web
Northern Virginia Java Users Group
(NOVAJUG) February 22, 2005 600pm -
900pm Presented by Brian Rosenthal Manager,
PlatinumSolutions brian.rosenthal_at_platinumsolution
s.com
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Who Am I

• Web apps developer since 1996
• Working with Java since 1998
• Working with XML Since 2000
• Manager PlatinumSolutions, Inc.
• Federal Government contractor
• Founding NOVAJUG member

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and why am I here?
Global Schema
State/Local Agencys Systems
Overlapping Systems
Our XML Schema
Legacy Database
Draft Cases
Import/Export(XML, CSV, PDF)
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Presentation Outline

• XForms Defined
• What are XForms?
• Why should I care?
• Client-side examples/demo
• Server-side examples/demo
• Current status of XForms

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Poll the Juggies

• Have you used
• HTML
• XHTML
• XML
• XSLT/XSL/XPath
• XForms

Out with the old
In with the new!
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What is XForms?

• A new emerging W3C standard
• The successor of HTML forms
• Will replace them in XHTML 2.0
• Addresses limitations of HTML forms
• Adds common functionality found in most
  form-applications

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Why XForms?

• Web forms are weak
• Diversity of frameworks used to overcome their
  weaknessesbut they are proprietary and/or
  commercial
• Server infrastructures have established industry
  standards for nearly all requirements - except
  form-processing.

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This Will Change Drastically!

• Forms will be portable from one server to
  another, serve different clients, provide rich
  validation and calculation, and allow complex
  logic without a single line of scripting code.
• Furthermore XForms is maintainable through clear
  separation of logic, data and presentation which
  allow a role-based development process.

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Working Group Requirements

• XForms should use XML, both for initial data and
  submitted data.
• The difference between a blank form and a
  filled-out form should be minimal and able to be
  represented as an XML document.
• Forms should be easy to route to multiple users
  and locations.
• XForms should separate purpose, presentation, and
  form data. Earlier, each section describing an
  HTML form control had to define two things how
  the control looked, and how it affected the form
  data set. XForms should cleanly separate these
  two aspects.
• XForms should provide the 20 percent of
  functionality needed to avoid 80 percent of all
  forms scripting.
• Popular features such as calculations and
  validations should be included in the language.
• XForms should be designed in such a way to
  encourage those using HTML forms to switch over
  by making sure that all the commonly used
  features in HTML forms are still possible in
  XForms.
• Taken from http//xformsinstitute.com/essentials/T
  aken

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Four Limitations of HTML Forms

• Dependency on scripting languages
• Difficulty in initializing form data
• Flat representation of data
• Assumption of a one-step submission process

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HTML Forms Limitation 1

• Dependency on scripting languages
• Marking controls as required
• Performing validations and calculations
• Displaying error messages
• Managing dynamic layout
• which results in complex documents
• Time-consuming
• Costly

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XForms Advantage 1

• Reduces the need for script
• Defines a framework for simple, XPath-based
  calculations and validations
• Provides better user feedback on the status of
  the form, through dynamic features such as
  repeating tables and optional sections, and
  through a system of XForms Actionselements that
  cause commonly needed actions such as setting
  focus or changing a data value.

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HTML Forms Limitation 2

• Difficulty of initializing form data
• Many options not as easy as they should be
• Often memory or processor intensive in
  large-scale applications

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XForms Advantage 2

• Form data provided from an initial XML file,
  which can be external to the form definition.
• Since XForms is also flexible enough to deal
  directly with most XML data formats, piping
  initial data into a form is typically a simple
  matter of pointing a src attribute to an existing
  XML data source.

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HTML Forms Limitation 3

• Encoding formats, urlencoded or multipart,
  represent "flat" data, or simply name/value
  pairs.
• Many types of forms would benefit from a richer
  data representation.

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XForms Advantage 3

• XML is a superior foundation for most business
  documents.
• Since XML support is a fundamental requirement,
  XForms excels at helping users create those kinds
  of documents.

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HTML Forms Limitation 4

• A fundamental design flaw in HTML forms a hidden
  assumption of a one-step processfrom a client to
  a serverwith processing finishing there.

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XForms Advantage 4

• XForms allows form data to be routed as needed.
• At each stop, the data may be loaded into a form
  for editing all or parts of the document, and
  resubmitted.
• Repeat as necessary.

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Simple XHTML Form

• ltform action"http//www.novajug.com/cgi-bin/pizza
  .pl" namepizza-poll"gt
• ltpgtPoll Meat or Veggie?lt/pgt
• ltlabel for"radio1"gtMeatlt/labelgt
• ltinput type"radio" namelovers" id"radio1"
  value"meat"/gtltbr/gt
• ltlabel for"radio2"gtVeggielt/labelgt
• ltinput type"radio" name"lovers" id"radio2"
  value"veggies"/gtltbr/gt
• ltlabel for"radio3"gtOther (please
  specify)lt/labelgt
• ltinput type"radio" name"lovers id"radio3"
  value"other"/gtltbr/gt
• ltinput type"text" name"othersel"/gt
• lt/formgt

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Simple XForms Form("lazy author" style)

• ltselect1 ref"mainsel" appearance"radio"
  selection"open"gt
• ltlabelgtPoll Meat or Veggie?lt/labelgt
• ltitemgt
• ltlabelgtMeatlt/labelgt
• ltvaluegtmeatlt/valuegt
• lt/itemgt
• ltitemgt
• ltlabelgtVeggielt/labelgt
• ltvaluegtveggielt/valuegt
• lt/itemgt
• lt/select1gt

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Initial Impressions?

• "Other, please specify" is implicit, since XForms
  supports the concept of "open selection" lists.
• To be able to submit this XForm, a small bit of
  markup is required in the head section of the
  document.
• XML model exists elsewhere.

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Example 1 Client Side XForms

• Namespaces, Styles
• Model, Submission
• Presentation (controls text)
• lt!-- Live Demo --gt

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XSmiles Browser
Results in
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The Model

• Two most important jobs
• Specify structure of XML data created by a form
• Sample XML document used here
• Can use src attribute to point to an external
  file
• Can identify a W3C schema file w/info about
  constraints
• Defines what happens when the form gets submitted

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The Model cont.

• Other observations
• Submission element can have many attributes
• In a production application, wed likely post the
  document to a process that uses the data

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The Display Form

• XForms is HTML-like, but with one crucial
  difference
• XForms lets you specify where in the model
  instance to plug in the entered value upon
  submission of the form.
• The xfinstance elements model and ref
  attributes show where to put the data upon
  submission

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The Display Form cont.

• CSS should look familiar
• One exception The pipe symbol
• Used instead of a colon to separate namespace
  prefix from rest of name
• Width property used because XForms input
  elements have no width attribute

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Example 2 Server-Side XForms

• Required fields, form field validation
• Field-level error messages
• Context-sensitive help
• Tool-tips
• Sticky forms
• Multi-occurrence, multi-value
• Other, please specify (version 2.7)
• lt! Live Demo --gt

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Orbeon Presentation Server
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Server-side XForms

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In Summary XForms

• Next generation of HTML forms
• Richer and more flexible than HTML forms
• Will be the forms standard in XHTML 2.0
• Platform and device independent
• Separates data and logic from presentation
• Uses XML to define form data
• Stores and transports data in XML documents
• Contains features like calculations and
  validations of forms
• Reduces or eliminates the need for scripting
• A W3C Recommendation

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Resources

• XForms 1.0 W3C Recommendation http//www.w3.org/T
  R/xforms/
• Dubinkos O'Reilly XForms Essentials
  http//xformsinstitute.com/essentials/
• XForms Data Typeshttp//www.w3schools.com/xforms/
  xforms_typeref.asp
• Ten Favorite XForms Engineshttp//www.xml.com/pub
  /a/2003/09/10/xforms.html
• Mozilla XForms Projecthttp//www.mozilla.org/proj
  ects/xforms/
• XSmiles Browserhttp//www.xsmiles.org
• Orbeon Presentation Serverhttp//www.orbeon.com/s
  oftware/

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Finally

• Slides available for download
• http//www.platinumsolutions.com/resources
• We are hiring! Please contact
• http//www.platinumsolutions.com/careers/
• hr_at_platinumsolutions.com