Building Flash-based websites using Flex Lesson 8 – Remote Data by Alex goh, associate trainer @ LAB School ( http://lab.edu.sg/ ), Adobe Authorized Training Centre, Singapore

1. Building Flash-based websites using Flex
Lesson 8 – Remote Data
Alex Goh
info@alekkus.com

2. Agenda
● Introduction to XML
● Managing special characters in XML
● XML in Flex
● Extracting XML in Flex
● JSON

3. Introduction to XML
● Extensible Markup Language (XML) is a type of markup language for
structuring data hierarchically.
● XML is tag-based, like HTML/MXML, but is designed for representing
information rather than controlling visual display.
● Most commonly used to represent data passed from a remote server.

4. Introduction to XML
● ECMAScript for XML (E4X) is the latest standard for reading and writing XML
documents.
● One of the most significant changes to ActionScript 3.0 is its native support
for E4X. This allowsdevelopers to work seamlessly with XML in their programs
without additional parsing.

5. Managing Special Characters in XML
● Certain characters are reserved for an internal use in XML documents. These
include the less than (<) and greater than (>) signs, which mark the beginning
and end of tag names.
● If we need to include reserved characters in text within an XML node, we can
either use:
● a CDATA declaration; or
● escape codes to represent the character.
● A sample list of reserved characters and their corresponding escape codes

6. Managing Special Characters in XML
e.g.

7. XML in Flex
● Following are the relevant XML classes:
● XML – an XML object with a valid xml string
● XMLList – an array of XML objects
● XMLListCollection – an “ArrayCollection” of XML objects
● e.g.

8. Extracting Data from XML
e.g.
Alert.show( sales.item[0].type ); //apples
Alert.show( sales.item[2].price ); //5.16

9. JSON
● JavaScript Object Notation (JSON) is another data format that is widely used
for representing data from the server.
● Originally made for JavaScript and AJAX.
● JSON is not natively supported in Flex, requires a plug-in library from Adobe -
http://labs.adobe.com/wiki/index.php/ActionScript_3:resources:apis:libraries#corelib
e.g.