ADOBE® FLEX® 3: PROGRAMMING ACTIONSCRIPT™ 3.0

ADOBE FLEX 3

Developer Guide

418

Microsoft changed the way streaming media is handled in Microsoft Internet Information Services (IIS) 6.0 web

server from earlier versions. Earlier versions of IIS do not require any modification to stream Flash Video. In IIS 6.0,

the default web server that comes with Windows 2003, the server requires a MIME type to recognize that FLV files

are streaming media.

When SWF files that stream external FLV files are placed on Microsoft Windows Server® 2003 and are viewed in a

browser, the SWF file plays correctly, but the FLV video does not stream. This issue affects all FLV files placed on

Windows Server 2003, including files you make with earlier versions of the Flash authoring tool, the Macromedia

Flash Video Kit for Dreamweaver MX 2004 from Adobe. These files work correctly if you test them on other

operating systems.

For information about configuring Microsoft Windows 2003 and Microsoft IIS Server 6.0 to stream FLV video, see

www.adobe.com/go/tn_19439.

About targeting local FLV files on the Macintosh

If you attempt to play a local FLV from a non-system drive on an Apple® Macintosh® computer by using a path that

uses a relative slash (/), the video will not play. Non-system drives include, but are not limited to, CD-ROMs, parti-

tioned hard disks, removable storage media, and connected storage devices.

Note: The reason for this failure is a limitation of the operating system, not a limitation in Flash Player.

For an FLV file to play from a non-system drive on a Macintosh, refer to it with an absolute path using a colon-based

notation (:) rather than slash-based notation (/). The following list shows the difference in the two kinds of notation:

• Slash-based notation: myDrive/myFolder/myFLV.flv

• Colon-based notation: (Mac OS®) myDrive:myFolder:myFLV.flv

You can also create a projector file for a CD-ROM you intend to use for Macintosh playback. For the latest infor-

mation on Mac OS CD-ROMs and FLV files, see www.adobe.com/go/3121b301.

Example: Video Jukebox

The following example builds a simple video jukebox which dynamically loads a list of videos to play back in a

sequential order. This allows you to build an application that lets a user browse through a series of video tutorials, or

perhaps specifies which advertisements should be played back before delivering the user’s requested video. This

example demonstrates the following features of ActionScript 3.0:

• Updating a playhead based on a video file’s playback progress

• Listening for and parsing a video file’s metadata

• Handling specific codes in a net stream

• Loading, playing, pausing, and stopping a dynamically loaded FLV

• Resizing a video object on the display list based on the net stream’s metadata

To get the application files for this sample, see www.adobe.com/go/learn_programmingAS3samples_flash. The

Video Jukebox application files can be found in the folder Samples/VideoJukebox. The application consists of the

following files:

ADOBE FLEX 3

Developer Guide

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Loading an external video playlist file

The external playlist.xml file specifies which videos to load, and the order to play them back in. In order to load the

XML file, you need to use a URLLoader object and a URLRequest object, as seen in the following code:

uldr = new URLLoader();

uldr.addEventListener(Event.COMPLETE, xmlCompleteHandler);

uldr.load(new URLRequest(PLAYLIST_XML_URL));

This code is placed in the VideoJukebox class’s constructor so the file is loaded before any other code is run. As soon

as the XML file has finished loading, the

xmlCompleteHandler() method is called which parses the external file

into an XML object, as seen in the following code:

private function xmlCompleteHandler(event:Event):void

{

playlist = XML(event.target.data);

videosXML = playlist.video;

main();

}

The playlist XML object contains the raw XML from the external file, whereas the videosXML is an XMLList object

which contains just the video nodes. A sample playlist.xml file can be seen in the following snippet:

<videos>

<video url="video/caption_video.flv" />

<video url="video/cuepoints.flv" />

<video url="video/water.flv" />

</videos>

Finally, the xmlCompleteHandler() method calls the main() method which sets up the various component

instances on the display list, as well as the NetConnection and NetStream objects which are used to load the external

FLV files.

Creating the user interface

To build the user interface you need to drag five Button instances onto the display list and give them the following

instance names:

playButton, pauseButton, stopButton, backButton, and forwardButton.

For each of these Button instances, you’ll need to assign a handler for the

click event, as seen in the following

snippet:

playButton.addEventListener(MouseEvent.CLICK, buttonClickHandler);

pauseButton.addEventListener(MouseEvent.CLICK, buttonClickHandler);

stopButton.addEventListener(MouseEvent.CLICK, buttonClickHandler);

backButton.addEventListener(MouseEvent.CLICK, buttonClickHandler);

forwardButton.addEventListener(MouseEvent.CLICK, buttonClickHandler);

The buttonClickHandler() method uses a switch statement to determine which button instance was clicked, as

seen in the following code:

File Description

VideoJukebox.as The class that provides the main functionality of the application.

VideoJukebox.fla The main application file for Flash.

playlist.xml A file that lists which video files will be loaded into the video jukebox.