ActionScript 3.0 Design Patterns

202 | Chapter 5: Adapter Pattern

The feed URL (http://www.oreillynet.com/pub/feed/29) is specified in line 37. The

URLLoader( )method (line 40) loads this document over the Internet, and calls the

xmlLoaded( )function when loading is complete. ThexmlLoaded( )method is regis-

tered as a listener function (line 41) because loading data is an asynchronous opera-

tion requiring notification when the process is completed. It is important that the

default namespace be set if a namespace is specified in the XML document (lines 50-

53). This enables E4X to do proper validation while parsing the XML document. The

for each statement accesses each book title (lines 55-58) and adds it to the

ListDisplayField adapter. Figure 5-7 shows the output from the example.

53 }

54 // populate the ListDisplayField with new book titles

55 for each (var bookTitle:XML in xml..entry.title)

56 {

57 newBookListField.addItem(bookTitle.toString( ));

58 }

59 }

60 }

61 }

Figure 5-7. The O’Reilly new books list displayed using the ListDisplayField adapter

Example 5-17. Main.as (document class)