XML (Extensible Markup Language

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Aldous Hancock
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1 XML (Extensible Markup Language XML is a markup language. XML stands for extensible Markup Language. The XML standard was created by W3C to provide an easy to use and standardized way to store self describing data (self describing data is data that describes both its content and its structure).

2 Communication Between Application XML is nothing by itself. XML is more of a "common ground" standard. The main benefit of XML is that you can use it to take data from a program like MSSQL (Microsoft SQL), convert it into XML, then share that XML with a slough of other programs and platforms What makes XML truly powerful is the international acceptance it has received. Many individuals and corporations have put forth their hard work to make XML interfaces for databases, programming, office application, mobile phones and more.

3 Applications of XML * Cell Phones - XML data is sent to some cell phones. The data is then formatted by the specification of the cell phone software designer to display text or images, and even to play sounds! * File Converters - Many applications have been written to convert existing documents into the XML standard. An example is a PDF to XML converter. * VoiceXML - Converts XML documents into an audio format so that you can listen to an XML document.

4 Free XML Viewer Internet Explorer 6.0 supports viewing XML files. You can download IE 6.0 from Microsoft's Website. Internet Explorer 6.0 has special color coding the make XML documents easier to read. Firefox XML Viewer: Firefox has some of the same features as Internet Explorer. You can download Mozilla's Firefox from Mozilla.com. Free XML Editors: There are many free XML editors available for download on the internet. Here are a few we have found useful: * XML Cooktop * XML Mind Standard Edition * Pete's XML Editor

5 XML Syntax: XML Code: <?xml version="1.0" encoding="iso "?> <class_list> <student> <name>robert</name> <grade>a+</grade> </student> <student> <name>lenard</name> <grade>a-</grade> </student> </class_list>

6 XML code. <?xml version="1.0" encoding="iso "?> This line with special symbols and attributes is what is referred to as the XML declaration. It simply states what version of XML you are using and the type of encoding you are using XML Tag The XML tag is very similar to that of the HTML tag. Each element is marked with an opening tag and a closing tag. <name>robert</name> <grade>a+</grade>

7 XML Elements They contain the opening and closing tags, child elements, and data. <student> <name>robert</name> <grade>a+</grade> </student> XML Attribute An attribute appears within the opening tag of an element. <student active="true"> <name>robert</name> <grade>a+</grade> </student>

8 XML Attribute Quotation Usage The types of quotes that you use around your attribute values is entirely up to you. Both the single quote (') and the double quote (") are perfectly fine to use in your XML documents. <student nickname=rob "The Dog''> <name>robert</name> <grade>a+</grade> </student> <student group="pete's Pandas"> <name>robert</name> <grade>a+</grade> </student>

9 XML Comment Syntax <?xml version="1.0" encoding="iso "?>  <class_list> <student> <name>robert</name> <grade>a+</grade> </student> <student> <name>lenard</name> <grade>a-</grade> </student> </class_list>

10 XML Commenting out XML To temporarily remove some XML code from your XML document. <?xml version="1.0" encoding="iso "?> <class_list> <student> <name>robert</name> <grade>a+</grade> </student>  </class_list>

11 XML Prolog The prolog is an optional component of the XML document. If included, the prolog must be appear before the root element. A prolog consists of two parts: the XML declaration and the Document Type Declaration (DTD). Depending on your needs, you can choose to include both, either, or neither of these items in your XML document. <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" " transitional.dtd">

12 *!DOCTYPE - Tell the XML processor that this piece of code defines the Document Type Definition * html - Specifies the root element of the XML document. Here our example is an HTML file, which has <html> as the root element. * PUBLIC - Specifies that this a publicly available DTD. * "-//W3C//D..." - The definition of the public document. Describing this is beyond the scope of this tutorial. * " - The physical location of the DTD. Notice how this DTD resides on w3's servers.

13 XML Nesting When an element appears within another element, it is said that the inner element is "nested". The term nested can be related directly to the word "nest". If an element is nested within another element, then it is surrounded, protected, or encapsulated by the outer element Example A <phonebook> <number> <name> </number> </name> </phonebook>

14 Example B <phonebook> <number> <name> </name> </number> </phonebook> All elements are closed in the order that they were opened. Those elements which were opened first are closed last. Example B is what example A must look like to be a well-formed XML document.

15 XML Namespaces XML was designed to be a very robust markup language that could be used in many different applications. However, with XML being able to communicate between so many different platforms, there is one problem that tends to occur. <?xml version="1.0" encoding="iso "?> <html> <body> <p>welcome to my Health Resource</p> </body> <body> <height>6ft</height> <weight>155 lbs</weight> </body> Two very different elements that want to use the same name: body. The solution to this problem is to create XML Namespaces,

16 XML Documents: Valid Versus Well-Formed In XML, there are three ways to measure a document's validity: valid, well-formed, and broken. * One Root Element - The XML document may only have one root element. See our Root Element Lesson for more information. * Proper Nesting - XML elements must be closed in the order they are opened. See our Nesting Lesson for more information. * Well-Formed Entities - Any entities that are referenced in the document must also be well-formed. See our Entity Lesson for more information.

17 Broken XML Code: < > <to>mr. Garcia <body>hello there! How are we today?</to> </body> </ > Well-Formed XML Code: < > <to>mr. Garcia</to> <body>hello there! How are we today?</body> </ > The error in the first example was:the document suffers from improper nesting. The body element was opened inside the to element, yet body was not closed before the to element was closed!

18 XML Tree: The great benefit about XML is that the document itself describes the structure of data. inventory is the root element.

19 XML The Tree Structure

20 Structure of an XML Document

21 Tree Structure <root> <child> <subchild>...</subchild> </child> </root>

24 Entity References If you place a character like "<" inside an XML element, it will generate an error because the parser interprets it as the start of a new element. <message>if salary < 1000 then</message> <message>if salary < 1000 then</message> There are 5 predefined entity references in XML: < < less than > > greater than & & ampersand ' ' apostrophe " " quotation mark

25 XML(Table)

26 XPath Finding Information XPath is the solution to finding information in an XML document. XPath uses expressions to find elements, attributes, and other information in your XML. If you have an XML document that contained a bunch of your favorite books, each with author children elements, you can use a one line XPath expression to find all the authors of your favorite books! The most common place people might see XPath expressions are in XSLT (Extensible Stylesheet Language Transformation).

27 Structure of an XML Document

28 Structure of an XML Document

29 Structure of an XML Document

30 Structure of an XML Document

31 Structure of an XML Document

32 Structure of an XML Document

33 Structure of an XML Document

34 XML is Used to Create New Internet Languages A lot of new Internet languages are created with XML. Here are some examples: * XHTML the latest version of HTML * WSDL for describing available web services * WAP and WML as markup languages for handheld devices * RSS languages for news feeds * RDF and OWL for describing resources and ontology * SMIL for describing multimedia for the web

35 SMIL 2.0 XML for Web Multimedia SMIL stands for Synchronized Multimedia Integration Language SMIL is pronounced "smile" SMIL is a language for describing audiovisual presentations SMIL is easy to learn and understand SMIL is an HTML-like language SMIL is written in XML SMIL presentations can be written using a text-editor SMIL is a W3C standard

36 What Can SMIL Do? Although plug-ins and media players have the ability to show many different types of media with varying support for interaction, only SMIL offers the ability to define the presentation in the form of text as a script. This feature could be called media composition. Also, SMIL offers accessibility options and powerful features not present in other media players.

37 Implementing SMIL Common SMIL implementations * Internet or Intranet presentations. * Slide show presentations. * Presentations which link to other SMIL files. * Presentations which have Control buttons (stop, start, next,...) * Defining sequences and duration of multimedia elements. * Defining position and visibility of multimedia elements. * Displaying multiple media types such as audio, video, text * Displaying multiple files at the same time. * Displaying files from multiple web servers. Currently, SMIL's most widespread usage is with MMS. MMS (Multimedia Messaging System) is a mobile device technology

38 Guidelines and Rules SMIL documents look a lot like HTML. SMIL files need to be written according to the following rules: * SMIL documents must follow the XML rules of well-formedness. * SMIL tags are case sensitive. * All SMIL tags are written with lowercase letters. * SMIL documents must start with a <smil> tag and end with a </smil> closing tag. * SMIL documents must contain a <body> tag for storing the contents of the presentation. * SMIL documents can have a <head> element (like HTML) for storing metadata information about the document itself, as well as presentation layout information.

39 <smil> <head> <layout>... </layout> </head> <body>... </body> </smil>

40 Image to our presentation <smil> <head> <layout> <root-layout width="300" height="300" background-color="white"/> <region id="cows" top="0" left="0" width="300" height="197"/> </layout> </head> <body> <img src="cows.jpg" region="cows"/> </body> </smil>

Copy and paste this URL, "http://html.tucows.com/designer/basictut/example1.

41 Copy and paste this URL, " mil" into your SMIL parser, i.e., RealPlayer, QuickTime, for an example of the SMIL presentation created

42 Multiple Regions We placed the new region, "text", 200 pixels from the top and 50 pixels from the left so that it's centered in our presentation.

43 Below is a table with the possible values we can give to the fit attribute.

44 We want to make the tucows.gif image fit perfectly within the region, so we would add fit="fill" to the text region. Below is an example.

45 Time Control You can also control how long you want a certain piece of media to be display for by using the "dur" attribute. This attribute takes a numerical value in seconds with the letter "s" after the number. For example, lets say we want the cows to be displayed for 10 seconds and the rest of the images for only 5. We would add "dur="10s"" to the cow's img tag and "dur="5s"" to the rest of the img tags. Below is what our code would look like.

46 This should display the TUCOWS text image, then the HTML text image during a span of 10 seconds.

47 SMIL for phones MMS uses SMIL to define the layout of multimedia content. SMIL was adopted because it was a well-defined, standard language to describe the layout and timing of the content inside MMS messages.

XML. XML Syntax. An example of XML:

XML. XML Syntax. An example of XML: XML Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable. Defined in the XML 1.0 Specification