ActionScript's powerful XML support is based on E4X. E4X stands for ECMAScript for XML and is a Document Object Model (DOM) interface for XML. E4X makes XML a first-class citizen in ActionScript.
Learn more about ActionScript XML in Flex at Flex After Dark...
Timer is a utility class in the flash.utils package. A timer's job is to fire off events at specified intervals.Timer instance and start it.import flash.utils.Timer;
import flash.events.TimerEvent;
// create a timer which fires every second (1000 ms)
var timer:Timer = new Timer( 1000 );
// add a listener to the timer
timer.addEventListener( TimerEvent.TIMER, handleTimerEvent );
// start the timer
timer.start();
Learn more about the ActionScript Timer at Flex After Dark...
ActionScript and Java are both powerful, object-oriented languages with many similarities.
Both Java and ActionScript:
There are also many differences between ActionScript and Java.
Important differences between Java and ActionScript:
Flex's HTTPService is used to make HTTP requests and handle the results. When you call the HTTPService object's send() method, it makes an HTTP request to the specified URL, and an HTTP response is returned (asynchrnously).
The HTTPService is part of Flex's Remoting/RPC library.
Making an HTTP request in ActionScript:
In a lot of programming languages we're use to seeing "getter and setter" functions "wrapped" around private properties. The idea is to encapsulate the access of variables behind these "accessor" functions.
You won't see nearly as many getter/setter functions in ActionScript. It's not because of laziness or "bad OOP". It is because ActionScript has support for special get and set functions that can encapsulate property access behind function calls, but without changing the property access syntax.
public class PersonLearn more about ActionScript Get/Set Functions at Flex After Dark...
{
private var _name:String;
public function get name():String
{
return this.name;
}
public function set name( value:String ):void
{
this.name = value;
}
}
E4X stands for ECMAScript for XML. (Remember that ActionScript is ECMAScript.)
E4X makes XML a first-class citizen in ActionScript.
var xmlAlbum:XML =
<album name="Sky Blue Sky" artist="Wilco">
<tracks>
<track name="Either Way" seconds="187"/>
<track name="You Are My Face" seconds="278"/>
<track name="Impossible Germany" seconds="358"/>
<track name="Sky Blue Sky" seconds="203"/>
<track name="Side With The Seeds" seconds="256"/>
<track name="Shake It Off" seconds="342"/>
<track name="Please Be Patient With Me" seconds="199"/>
<track name="Hate It Here" seconds="273"/>
<track name="Leave Me (Like You Found Me)" seconds=""/>
<track name="Walken" seconds="267"/>
<track name="What Light" seconds="216"/>
<track name="On And On And On" seconds=""/>
</tracks>
Learn more about Flex and ActionScript support for XML via E4X at Flex After Dark...
public dynamic class DynamicClassNote the dynamic keyword used in the class declaration. So even though DynamicClass has not properties or functions defined (besides those of its super-class, Object), we can still attach properties and functions to it dynamically.
{
public DynamicClass()
{
}
}
Characteristics of ActionScript: