ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Drag and drop in AIR
get relativePath():String — Provides the path, including file name, for the created file. The path is resolved
relative to the drop location chosen by the user in the drag-and-drop operation. To make sure that the path uses
the proper separator character for the host operating system, use the File.separator constant when specifying
paths containing directories. You can add a setter function or use a constructor parameter to allow the path to be
set at runtime.
get isAsync():Boolean — Informs the AIR runtime whether the data provider object provides it’s data
asynchronously or synchronously.
close():void — Called by the runtime when the data is fully read (or an error prevents further reading). You can
use this function to cleanup resources.
reportError( e:ErrorEvent ):void — Called by the runtime when an error reading the data occurs.
All of the IFilePromise methods are called by the runtime during a drag-and-drop operation involving the file promise.
Typically, your application logic should not call any of these methods directly.
Using a synchronous data provider in a file promise
Adobe AIR 2 and later
The simplest way to implement the IFilePromise interface is to use a synchronous data provider object, such as a
ByteArray or a synchronous FileStream. In the following example, a ByteArray object is created, filled with data, and
returned when the open() method is called.
package
{
import flash.desktop.IFilePromise;
import flash.events.ErrorEvent;
import flash.utils.ByteArray;
import flash.utils.IDataInput;
public class SynchronousFilePromise implements IFilePromise
{
private const fileSize:int = 5000; //size of file data
private var filePath:String = "SynchronousFile.txt";
public function get relativePath():String
{
return filePath;
}
public function get isAsync():Boolean
{
return false;
}
public function open():IDataInput
{
var fileContents:ByteArray = new ByteArray();
//Create some arbitrary data for the file
for( var i:int = 0; i < fileSize; i++ )
Last updated 6/6/2012
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