ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Working with sound
File Description
com/example/program
mingas3/podcastplayer
/RSSItem.as
com/example/program
mingas3/podcastplayer
/SoundFacade.as
com/example/program
mingas3/podcastplayer
/URLService.as
An ActionScript class that holds data about an RSS item.
The main ActionScript class for the application. It encapsulates the methods and events of the Sound class and the
SoundChannel class and adds support for pausing and resuming playback.
An ActionScript class that retrieves data from a remote URL.
playerconfig.xml An XML file containing a list of RSS feeds that represent podcast channels.
comp/example/progra
mmingas3/utils/DateUt
il.as
Class that is used for easy date formatting (Flash only).
Reading RSS data for a podcast channel
Flash Player 9 and later, Adobe AIR 1.0 and later
The Podcast Player application starts by reading information about a number of podcast channels and their episodes:
1. First, the application reads an XML configuration file that contains a list of podcast channels and displays the list of
channels to the user.
2. When the user selects one of the podcast channels, it reads the RSS feed for the channel and displays a list of the
channel episodes.
This example uses the URLLoader utility class to retrieve text-based data from a remote location or a local file. The
Podcast Player first creates a URLLoader object to get a list of RSS feeds in XML format from the playerconfig.xml file.
Next, when the user selects a specific feed from the list, a new URLLoader object is created to read the RSS data from
that feed’s URL.
Simplifying sound loading and playback using the SoundFacade class
Flash Player 9 and later, Adobe AIR 1.0 and later
The ActionScript 3.0 sound architecture is powerful but complex. Applications that only need basic sound loading and
playback features can use a class that hides some of the complexity by providing a simpler set of method calls and
events. In the world of software design patterns, such a class is called a facade.
The SoundFacade class presents a single interface for performing the following tasks:
Loading sound files using a Sound object, a SoundLoaderContext object, and the SoundMixer class
Playing sound files using the Sound object and the SoundChannel object
Dispatching playback progress events
Pausing and resuming playback of the sound using the Sound object and the SoundChannel object
The SoundFacade class tries to offer most of the functionality of the ActionScript sound classes with less complexity.
The following code shows the class declaration, the class properties, and the SoundFacade() constructor method:
Last updated 6/6/2012
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