ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Drag and drop in AIR
SecurityErrorEvent.SECURITY_ERROR — Informs the runtime that a security error has occurred. The runtime
aborts file creation and calls the IFilePromise close() method.
HTTPStatusEvent.HTTP_STATUS — Used, along with httpResponseStatus, by the runtime to make sure that
the data available represents the desired content, rather than an error message (such as a 404 page). Objects based
on the HTTP protocol should dispatch this event.
HTTPStatusEvent.HTTP_RESPONSE_STATUS — Used, along with httpStatus, by the runtime to make sure
that the data available represents the desired content. Objects based on the HTTP protocol should dispatch this
event.
The data provider should dispatch these events in the following sequence:
1 open event
2 progress or socketData events
3 complete or close event
Note: The built-in objects, FileStream, Socket, and URLStream, dispatch the appropriate events automatically.
The following example creates a file promise using a custom, asynchronous data provider. The data provider class
extends ByteArray (for the IDataInput support) and implements the IEventDispatcher interface. At each timer event,
the object generates a chunk of data and dispatches a progress event to inform the runtime that the data is available.
When enough data has been produced, the object dispatches a complete event.
package
{
import flash.events.Event;
import flash.events.EventDispatcher;
import flash.events.IEventDispatcher;
import flash.events.ProgressEvent;
import flash.events.TimerEvent;
import flash.utils.ByteArray;
import flash.utils.Timer;
[Event(name="open", type="flash.events.Event.OPEN")]
[Event(name="complete", type="flash.events.Event.COMPLETE")]
[Event(name="progress", type="flash.events.ProgressEvent")]
[Event(name="ioError", type="flash.events.IOErrorEvent")]
[Event(name="securityError", type="flash.events.SecurityErrorEvent")]
public class AsyncDataProvider extends ByteArray implements IEventDispatcher
{
private var dispatcher:EventDispatcher = new EventDispatcher();
public var fileSize:int = 0; //The number of characters in the file
private const chunkSize:int = 1000; //Amount of data written per event
private var dispatchDataTimer:Timer = new Timer( 100 );
private var opened:Boolean = false;
public function AsyncDataProvider()
{
super();
dispatchDataTimer.addEventListener( TimerEvent.TIMER, generateData );
}
public function begin():void{
dispatchDataTimer.start();
}
Last updated 6/6/2012
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