upgrading to xhtml deco 3001 tutorial 1 – part 2 presented by ji soo yoon 19 february 2004 slides...
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Upgrading to XHTMLDECO 3001 Tutorial 1 – Part 2
Presented by Ji Soo Yoon19 February 2004
Slides adopted from http://faculty.northseattle.edu/jkent/it111/lecture_notes.html, http://www.w3schools.com/xhtml/default.asp, http://www.pint.com/classes, http://wally.cs.iupui.edu/n241-new/ and Beginning XHTML ©2000 Wrox Press
This is accomplished through the use of three DTDs: Transitional, Frameset, and Strict
Even though the XHTML DTDs are an improvement over HTML, they may still be too large for many types of user agents such as PDAs or mobile phones
Many of the elements found in XHTML 1.0, such as graphics, tables, and frames, may not be useable on many user agents
Creating XHTML Documents
Document Type Definition (DTD)
The World Wide Web Consortium (W3C) created XHTML to make the transition to XML-based Web pages easier
To facilitate the transition, the W3C provided three types of XHTML DTDs: Transitional, Frameset, and Strict
XHTML DTDs
W3C Recommendation: Use a Document Type Definition to identify the type of markup language used in a web page
XHTML 1.0 Strict May be considered to be the ‘core’ XHTML DTD Use this when you want really clean markup, free of presentational clutter Use this together with Cascading Style Sheets Use this whenever possible
XTML 1.0 Transitional Contains everything that is within the Strict DTD plus some additional tags and attributes Likely to be phased out in future versions of XHTML This is the least strict specification for XHTML 1.0 Use this when you need to take advantage of HTML's presentational features Use this when you want to support browsers that don't understand Cascading Style Sheets
XHTML 1.0 Frameset Contains everything that is within the Strict DTD plus some additional tags and attributes Likely to be phased out in future versions of XHTML Use this when you want to use HTML Frames to partition the browser window into two or more
frames
Strict DTD
The Strict DTD eliminates the elements that were deprecated in the Transitional DTD and Frameset DTD
Transitional DTD
Elements and attributes that are considered to be obsolete and that will eventually be eliminated are said to be deprecated.
The Transitional DTD allows you to continue using deprecated elements along with the well-formed document requirements of XML.
Transitional DTD
Frameset DTD
The Frameset DTD is identical to the transitional DTD, except that it includes the <frameset> and <frame> elements
Allows you to split the browser window into two or more frames, which are independent, scrollable portions of a Web browser window, with each frame capable of displaying a separate URL
DOCTYPE
All documents begin with a <!DOCTYPE> declaration The <!DOCTYPE> declaration states the XHTML version of the
document and the XHTML DTD (Transitional, Frameset, or Strict) with which the document complies
Modern browsers are aware of the <!DOCTYPE> and will examine it to determine what rendering mode to enter (standards vs. quirk)
Using the <!DOCTYPE> declaration allows validation software to identify the DTD being followed in a document, and verify that the document is syntactically correct all tags used are part of a particular specification and are being
used correctly
The <!DOCTYPE> Declaration
XHTML Version DOCTYPE
XTHML 1.0 Strict <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
XHTML 1.0 Transitional <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
XHTML 1.0 Frameset <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">
XHTML 1.1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
XHTML 2.0 (still in progress)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 2.0//EN" " http://www.w3.org/TR/xhtml2/DTD/xhtml2.dtd ">
XHTML Version Summary
XHTML Version Description
XTHML 1.0 Strict A reformulation of HTML 4.0 strict using XML. This language is rule enforcing and leaves all presentation duties to technologies such as Cascading Style Sheets (CSS).
XHTML 1.0 Transitional A reformulation of HTML as an XML application. The transitional form preserves many of the basic presentation features of HTML 4.0 transitional but applies the strict syntax rules of XML to HTML.
XHTML 1.1 A minor change to XHTML 1.0 that restructures the definition of XHTML 1.0 to modularize it for easy extension. It is not commonly used at the time of this writing and offers minor gains over XHTML 1.0.
XHTML 2.0 (still in progress)
A new implementation of XHTML circa 2003 that may not provide backward compatibility with XHTML 1.0 and traditional HTML. XHTML 2 will likely remove most or all presentational tags left in HTML and will introduce even more logical ideas to the language.
XHTMLElements and Attributes
The data contained within an element’s opening and closing tags is referred to as its content
You must close empty elements by adding a space and a slash before the tag’s closing bracket
Block-Level andInline Elements
Two basic types of elements can appear within a document’s <body> element: block-level and inline Block-level elements are elements that give a Web page
its structure Inline, or text-level, elements describe the text that
appears on a Web page
Unlike block-level elements, inline elements do not appear on their own lines; they appear within the line of the block-level element that contains them
Block-LevelInline Elements 2
Standard Attributes
You place attributes before the closing bracket of the starting tag, and you separate them from the tag name or other attributes with a space
Many XHTML attributes are unique to a specific element or can only be used with certain types of elements
XHTML also includes several standard, or common, attributes that are available to almost every element, with a few exceptions
Standard Attributes 2
Standard Attributes 3
In order to be a considerate resident of the international world of the Web, you should designate the language of your elements using the lang and xml:lang attributes
The lang attribute is used in HTML documents, whereas the xml:lang attribute is used in XML-based documents
Boolean Attributes
A Boolean attribute specifies one of two values: true or false
The presence of a Boolean attribute in an element’s opening tag indicates a value of “true”, whereas its absence indicates a value of “false”
When a Boolean attribute is not assigned a value, it is referred to as having a minimized form
Recall that all attribute values must appear within quotation marks
Boolean Attributes 2
This syntax also means that an attribute must be assigned a value For this reason, minimized Boolean attributes are illegal in
XHTML
You can still use Boolean attributes in XHTML provided you use their full form
You create the full form of a Boolean attribute by assigning the name of the other attribute itself as the attribute’s value
Required Elements
To better understand how an XHTML document is structured, in this section you study in detail the three elements that must be included in every XHTML document: the <html>, <head>, and <body> elements
The <html> Element
All HTML documents must include an <html> element, which tells a Web browser that the instructions between the opening and closing <html> tags are to be assembled into an HTML document
The <html> element is required and contains all the text and other elements that make up the HTML document
The <html> element is also the root element for XHTML documents and is required for XHTML documents to be well formed
The XHTML Namespace
All of the predefined elements in an XHTML document are organized within the XHTML namespace that you declare in the <html> element
In order to understand what a namespace is, recall that you must define your own elements and attributes in an XML document
You identify each element by the namespace to which it belongs
A namespace organizes the elements and attributes of an XML document into separate groups
The XHTML Namespace 2
For elements, you add the namespace and colon before the tag name in both the opening and closing tags
A default namespace is applied to all of the elements and attributes in an XHTML document, with the exception of elements and attributes to which local namespaces have been applied
You specify a default namespace for an XHTML document by using the xmlns namespace attribute in the <html> element
The <head> Element
The elements within a document’s head section contain information about the Web page itself
The document head does not actually display any information in a browser Rather, it is a parent element that can
contain several child elements
Child Elements of the <head> Element
A parent element is an element that contains other elements, known as child elements
The <body> Element
The document body is represented by the <body> element and contains other elements that define all of the content a user sees rendered in a browser
XHTML documents consist of elements that contain content, as opposed to HTML documents, which consist of content that contains elements
The <body> Element 2
In HTML, you can also use various attributes in the <body> element that affect the appearance of the document, such as the bgcolor attribute for setting the background color and the text attribute for setting the default color of text
Basic body elements such as the <p> and <br /> elements are some of the most frequently used elements in Web page authoring
Headings
Heading elements are used for emphasizing a document’s headings and subheadings, which helps provide structure by hierarchically organizing a document’s content
There are six heading elements, <h1> through <h6>
Paragraphs and Line Breaks
The paragraph (<p> … </p>) and line-break (<br />) elements provide the simplest way of adding white space to a document
White space refers to the empty areas on a page It makes a page easier to read and is more
visually appealing
Paragraphs and Line Breaks 2
It is tempting for beginning Web page authors to try and pack each page with as much information as possible, but experienced Web page authors know that the presence of white space is critical to the success of a page, whether you are creating a Web page or a traditional printed page
Horizontal Rules
The empty horizontal-rule (<hr />) element draws a horizontal rule on a Web page that acts as a section divider
Horizontal rules are useful visual elements for breaking up long documents
Although the <hr /> element is technically a block-level element, it cannot contain any content because it is an empty element
Comments
Comments are nonprinting lines that you place in your code to contain various types of remarks
XHTML comments begin with an opening comment tag <!– and end with a closing comment tag -->
First XHTML Page
<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE html PUBLIC "//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><html xmlns="http://www.w3.org/1999/xhtml"
xml:lang="en" lang="en"><head><title>My First XHTML Document</title></head><body><h2>My First HTML Document</h2><hr /><p>Hello, visitor</p><!-- No simple "Hello World" here --><p>Greetings from <a href=“http://…"> Ji Soo
Yoon</a></p><p>This page written by: <cite>Ji Soo Yoon</cite><br />© 2004 and beyond</p><p>Checking this page for validation <a href=“http://..">
click here</a></p></body></html>
For More Information
World Wide Web Consortium http://www.w3.org
Greg’s Web http://www.arch.usyd.edu.au/~g_smith
W3Schools http://www.w3schools.com
XHTML with examples http://wdvl.internet.com/Authoring/Languages/XML/XHTML/