An Example of a "Learning Process" Journal (using the 2 colored box format)

• Cascading Style Sheets: The Designer's Edge (2004) by Molly Holzschlag
• Learn XML in a Weekend (2002) by Erik Westermann
• Teach Yourself XML in 21 days (2003) by Steven Holzner.

6:10 am

This will be the beginning of my efforts to learn both XML and CSS. I bought three books on the topic while in Edmonton during the weekend and am excited about the topic, having read the first few pages of each book. Now to begin the actual learning.

I will begin with the Holzner book. It is the most detailed and up to date. I will use the Westermann book as a supplementary resource, reading it after each chapter in Holzner. The CSS book will wait until I get to that topic in Holzner (Day 8).

Teach Yourself XML in 21 days (2003) by Steven Holzner.

Day 1 [p. 9 - 41]

• "The name of the game in XML is data, because XML is all about storing yur data. ... Unlike HTML. XML is not about displaying your data." [p. 10]
• "... there are already many markup languages around." [p. 11]
• "... HTML is a very limited language. It's OK for creating standard Web pages, but it can't go much farther than that." [p. 12]
• "...XML is a meta-language, which means it's a language that lets you create your own markup language." [p. 12]
• "XML is meant for storing data, not displaying it." [p. 12]
• "... because XML documents are text, you can send them using the existing Internet technology that was built for HTML." [p. 12]
• "XML is a creation of the World Wide Web Consortium (W3C)" [p. 13]
• "XML version 1.0 is in recommendation form, and has been since October 6, 2000, which means it's an established standard." [p. 13]
• A check of the W3C website indicates that XML 1.1 is the latest version (Feb. 4, 2004) but they suggest that one use XML 1.0 Third Edition (Feb. 4, 2004) for the time being.
• <?xml?> is called an XML declaration. It has two attributes that indicate the version number and character encoding standard used in the document.
• An XML element is defined by a pair of tags, the opening tag and then the closing tag. Example: <element1> stuff </element1>
• "You are free to make up your own element names in XML, and that's XML's whole power - the capability to make your own markup."
• One may download XML code examples for this book [p. 5]
  http://www.samspublishing.com
• An XML processor can check:
  • that the XML code is well formed (i.e. follows syntax rules for nesting and open and closing tags)
  • that the XML code is valid (I.e. follows rules specified by your DTD [Document Type Definition]
• XML syntax rules may be specified by:
  • a DTD [Document Type Definition] or
  • an XML schema

The separation of data from its formatting is an important idea.

At the same time, this looks like two steps back from my present Dreamweaver approach. Now I need to learn about both XML and CSS. One immediate concern is whether there are authoring packages for actually using this (does Dreamweaver give me a good interface for XML?)

There is an example of the markup for an RTF file - it is horrific!

The statement that HTML is very limited is motivating, not discouraging. It is time to learn more about utilizing the Web.

It is time to visit the W3C home page. http://www.w3.org/

Here are the first few lines from the source code for the W3C home 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">

I am not too sure about the use of the ? yet, but I think it has something to do with "processing". Similarly, the next tag that begins with a ! is, I think, a comment tag. Hopefully I will be on top of this shortly.

Super. I now understand the first line of any XML file.

I have just found the information on page 5 for downloading the XML code files from the publisher. This worked fine. I have opened the first three files for chapter 1 and they are helpful simple examples of XML files.

Okay I must now learn about the two ways of specifying the XML syntax rules that my file will adhere to. The first of these two ways is called a DTD, a Document Type Definition.

Quiz [p. 41]

1. What's the main reason XML has become so popular in the last five years?
   XML provides a standard for sharing data files over the Internet.
2. What are the four differenct types of specifications that W3C publishes?
   It is important to realize that only the fourth type, called a recommendation, means that it has become an approved standard. The other three are variations of preliminary versions.
3. What's an XML element? What's an XML attribute?
   An XML element is any text plus the two tags at the beginning and end of the text. An XML attribute is something between double quotes and is located in the opening tag.
4. What are some of the requirements for an XML document to be well-formed?
   It must contain elements, and one element (the root element) must contain all of the other elements. The elements must be opened and closed and properly nested.
5. What are two XML constructs that let you specify an XML document's syntax so it can be checked for validity?
   A DTD (Document Type Definition) and an XML schema.

http://www.w3.org/XML/1999/XML-in-10-points [p. 37]

http://www.w3.org/Style/CSS/ [p. 37]

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/xmlsdk30/htm/xmtutxmltutorial.asp [p. 39]

http://www.digital-web.com/tutorials/tutorial_2002-06.shtml

10:30 am

• Download Amaya browser
• Download & install Opera browser
• Download & install XML Spy

• Although I was able to download the Amaya browser from the W3C site, I was not able to follow the instructions to install it. I quickly gave up as this appeared too technical, and I don't really need Amaya at the present time.
• I had no difficulty downloading & installing Opera. A quick check of basic browsing seemed to work just fine.
• I reviewed the details for downloading a 30-day free trial of the Home version. This will cost $69. US if I decide to keep it. It installed without difficulty, but I have yet to figure out how to use it.
• I think the next step will be to return to Holzner and read the Day 2 material.

11:30 am

• One needs to be familiar with:
  • XML Browsers (e.g. Internet Explorer, Netscape Navigator, Opera)
  • XML Editors (e.g. XML Spy)
  • XML Validators (e.g. W3C)
• XML markup includes:
  • tags (e.g. <...>)
  • general entity references (e.g. &...;)
  • parameter entity references (e.g. %...;)
• All XML files must begin with an XML declaration
  • <?xml version = "1.0" encoding = "UTF-8"?>
• Processing instructions begin with a <? and end with a ?>
• XML tags are case sensitive
• All XML files must have one root element that contains all of the other elements.

12:45 PM

I have read the Day 2 material. First I will make a few notes (see above box), then I want to try using XML Spy to see if I can create a valid file.

I am able to use XML Spy to create an XML file consisting of an XML declaration and a root element. But I am not yet able to add to this file!

1:15 PM

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