actionscript-book-FileIO-com-example-programmingas3-fileio-FileDownload.ax [swf] flex
package {
import flash.events.*;
import flash.net.FileReference;
import flash.net.URLRequest;
import mx.controls.Button;
import mx.controls.ProgressBar;
import mx.core.UIComponent;
public class @ax-actionscript-book-FileIO-com-example-programmingas3-fileio-FileDownload extends UIComponent {
// Hard-code the URL of file to download to user's computer.
private const DOWNLOAD_URL:String = "http://www.cs.vu.nl/~eliens/flex/test.zip";
private var fr:FileReference;
// Define reference to the download ProgressBar component.
private var pb:ProgressBar;
// Define reference to the "Cancel" button which will immediately stop the download in progress.
private var btn:Button;
public function @ax-actionscript-book-FileIO-com-example-programmingas3-fileio-FileDownload() {
}
Set references to the components, and add listeners for the OPEN, PROGRESS, and COMPLETE events.
public function init(pb:ProgressBar, btn:Button):void {
// Set up the references to the progress bar and cancel button, which are passed from the calling script.
this.pb = pb;
this.btn = btn;
fr = new FileReference();
fr.addEventListener(Event.OPEN, openHandler);
fr.addEventListener(ProgressEvent.PROGRESS, progressHandler);
fr.addEventListener(Event.COMPLETE, completeHandler);
}
Immediately cancel the download in progress and disable the cancel button.
public function cancelDownload():void {
fr.cancel();
pb.label = "DOWNLOAD CANCELLED";
btn.enabled = false;
}
Begin downloading the file specified in the DOWNLOAD_URL constant.
public function startDownload():void {
var request:URLRequest = new URLRequest();
request.url = DOWNLOAD_URL;
fr.download(request);
}
When the OPEN event has dispatched, change the progress bar's label and enable the "Cancel" button, which allows the user to abort the download operation.
private function openHandler(event:Event):void {
pb.label = "DOWNLOADING %3%%";
btn.enabled = true;
}
While the file is downloading, update the progress bar's status and label.
private function progressHandler(event:ProgressEvent):void {
pb.setProgress(event.bytesLoaded, event.bytesTotal);
}
Once the download has completed, change the progress bar's label and disable the "Cancel" button since the download is already completed.
private function completeHandler(event:Event):void {
pb.label = "DOWNLOAD COMPLETE";
pb.setProgress(0, 100);
btn.enabled = false;
}
}
}
(C) Æliens 27/08/2009
You may not copy or print any of this material without explicit permission of the author or the publisher. In case of other copyright issues, contact the author.
