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flash.net 
URLLoader 
Packageflash.net
Classpublic class URLLoader
InheritanceURLLoader Inheritance EventDispatcher Inheritance Object

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

The URLLoader class downloads data from a URL as text, binary data, or URL-encoded variables. It is useful for downloading text files, XML, or other information to be used in a dynamic, data-driven application.

A URLLoader object downloads all of the data from a URL before making it available to code in the applications. It sends out notifications about the progress of the download, which you can monitor through the bytesLoaded and bytesTotal properties, as well as through dispatched events.

When loading very large video files, such as FLV's, out-of-memory errors may occur.

When you use this class in Flash Player and in AIR application content in security sandboxes other than then application security sandbox, consider the following security model:

  • A SWF file in the local-with-filesystem sandbox may not load data from, or provide data to, a resource that is in the network sandbox.
  • By default, the calling SWF file and the URL you load must be in exactly the same domain. For example, a SWF file at www.adobe.com can load data only from sources that are also at www.adobe.com. To load data from a different domain, place a URL policy file on the server hosting the data.

For more information related to security, see the Flash Player Developer Center Topic: Security.

View the examples

See also



Public Properties
 PropertyDefined By
  bytesLoaded : uint = 0
Indicates the number of bytes that have been loaded thus far during the load operation.
URLLoader
  bytesTotal : uint = 0
Indicates the total number of bytes in the downloaded data.
URLLoader
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  data : *
The data received from the load operation.
URLLoader
  dataFormat : String = "text"
Controls whether the downloaded data is received as text (URLLoaderDataFormat.TEXT), raw binary data (URLLoaderDataFormat.BINARY), or URL-encoded variables (URLLoaderDataFormat.VARIABLES).
URLLoader
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
Public Methods
 MethodDefined By
  
URLLoader(request:URLRequest = null)
Creates a URLLoader object.
URLLoader
  
addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void
[override] Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event.
URLLoader
  
Closes the load operation in progress.
URLLoader
 Inherited
Dispatches an event into the event flow.
EventDispatcher
 Inherited
Checks whether the EventDispatcher object has any listeners registered for a specific type of event.
EventDispatcher
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
  
Sends and loads data from the specified URL.
URLLoader
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes a listener from the EventDispatcher object.
EventDispatcher
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
 Inherited
Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.
EventDispatcher
Events
 Event Summary Defined By
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.EventDispatcher
  Dispatched after all the received data is decoded and placed in the data property of the URLLoader object.URLLoader
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.EventDispatcher
  Dispatched if a call to the load() method attempts to access data over HTTP, and Adobe AIR is able to detect and return the status code for the request.URLLoader
  Dispatched if a call to URLLoader.load() attempts to access data over HTTP.URLLoader
  Dispatched if a call to URLLoader.load() results in a fatal error that terminates the download.URLLoader
  Dispatched when the download operation commences following a call to the URLLoader.load() method.URLLoader
  Dispatched when data is received as the download operation progresses.URLLoader
  Dispatched if a call to URLLoader.load() attempts to load data from a server outside the security sandbox.URLLoader
Property Detail

bytesLoaded

property
public var bytesLoaded:uint = 0

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Indicates the number of bytes that have been loaded thus far during the load operation.

bytesTotal

property 
public var bytesTotal:uint = 0

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Indicates the total number of bytes in the downloaded data. This property contains 0 while the load operation is in progress and is populated when the operation is complete. Also, a missing Content-Length header will result in bytesTotal being indeterminate.

data

property 
public var data:*

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

The data received from the load operation. This property is populated only when the load operation is complete. The format of the data depends on the setting of the dataFormat property:

If the dataFormat property is URLLoaderDataFormat.TEXT, the received data is a string containing the text of the loaded file.

If the dataFormat property is URLLoaderDataFormat.BINARY, the received data is a ByteArray object containing the raw binary data.

If the dataFormat property is URLLoaderDataFormat.VARIABLES, the received data is a URLVariables object containing the URL-encoded variables.

See also


Example  ( How to use this example )
The following example shows how you can load an external text file with URL encoded variables into an ActionScript 3.0 document using the URLLoader class and setting the dataFormat property to the URLLoaderDataFormat.VARIABLES constant ("variables"). Example provided by ActionScriptExamples.com.
//params.txt is a local file that includes: firstName=Tom&lastName=Jones
var lbl:TextField = new TextField();
var urlRequest:URLRequest = new URLRequest("params.txt");
var urlLoader:URLLoader = new URLLoader();
urlLoader.dataFormat = URLLoaderDataFormat.VARIABLES;
urlLoader.addEventListener(Event.COMPLETE, urlLoader_complete);
urlLoader.load(urlRequest);
 
function urlLoader_complete(evt:Event):void {
    lbl.text = urlLoader.data.lastName + "," + urlLoader.data.firstName;
    addChild(lbl);
}

dataFormat

property 
public var dataFormat:String = "text"

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Controls whether the downloaded data is received as text (URLLoaderDataFormat.TEXT), raw binary data (URLLoaderDataFormat.BINARY), or URL-encoded variables (URLLoaderDataFormat.VARIABLES).

If the value of the dataFormat property is URLLoaderDataFormat.TEXT, the received data is a string containing the text of the loaded file.

If the value of the dataFormat property is URLLoaderDataFormat.BINARY, the received data is a ByteArray object containing the raw binary data.

If the value of the dataFormat property is URLLoaderDataFormat.VARIABLES, the received data is a URLVariables object containing the URL-encoded variables.

The default value is URLLoaderDataFormat.TEXT.

See also


Example  ( How to use this example )
The following example shows how you can load external text files. Use the URLRequest and URLLoader classes, and then listen for the complete event. Example provided by ActionScriptExamples.com.
var PATH:String = "lorem.txt";
var urlRequest:URLRequest = new URLRequest(PATH);
var urlLoader:URLLoader = new URLLoader();
urlLoader.dataFormat = URLLoaderDataFormat.TEXT; // default
urlLoader.addEventListener(Event.COMPLETE, urlLoader_complete);
urlLoader.load(urlRequest);
 
function urlLoader_complete(evt:Event):void {
    textArea.text = urlLoader.data;
}
Constructor Detail

URLLoader

()Constructor
public function URLLoader(request:URLRequest = null)

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Creates a URLLoader object.

Parameters
request:URLRequest (default = null) — A URLRequest object specifying the URL to download. If this parameter is omitted, no load operation begins. If specified, the load operation begins immediately (see the load entry for more information).

See also

Method Detail

addEventListener

()method
override public function addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event. You can register event listeners on all nodes in the display list for a specific type of event, phase, and priority.

After you successfully register an event listener, you cannot change its priority through additional calls to addEventListener(). To change a listener's priority, you must first call removeListener(). Then you can register the listener again with the new priority level.

Keep in mind that after the listener is registered, subsequent calls to addEventListener() with a different type or useCapture value result in the creation of a separate listener registration. For example, if you first register a listener with useCapture set to true, it listens only during the capture phase. If you call addEventListener() again using the same listener object, but with useCapture set to false, you have two separate listeners: one that listens during the capture phase and another that listens during the target and bubbling phases.

You cannot register an event listener for only the target phase or the bubbling phase. Those phases are coupled during registration because bubbling applies only to the ancestors of the target node.

If you no longer need an event listener, remove it by calling removeEventListener(), or memory problems could result. Event listeners are not automatically removed from memory because the garbage collector does not remove the listener as long as the dispatching object exists (unless the useWeakReference parameter is set to true).

Copying an EventDispatcher instance does not copy the event listeners attached to it. (If your newly created node needs an event listener, you must attach the listener after creating the node.) However, if you move an EventDispatcher instance, the event listeners attached to it move along with it.

If the event listener is being registered on a node while an event is being processed on this node, the event listener is not triggered during the current phase but can be triggered during a later phase in the event flow, such as the bubbling phase.

If an event listener is removed from a node while an event is being processed on the node, it is still triggered by the current actions. After it is removed, the event listener is never invoked again (unless registered again for future processing).

Parameters

type:String — The type of event.
 
listener:Function — The listener function that processes the event. This function must accept an Event object as its only parameter and must return nothing, as this example shows:
function(evt:Event):void

The function can have any name.

 
useCapture:Boolean (default = false)Determines whether the listener works in the capture phase or the target and bubbling phases. If useCapture is set to true, the listener processes the event only during the capture phase and not in the target or bubbling phase. If useCapture is false, the listener processes the event only during the target or bubbling phase. To listen for the event in all three phases, call addEventListener twice, once with useCapture set to true, then again with useCapture set to false.
 
priority:int (default = 0) — The priority level of the event listener. The priority is designated by a signed 32-bit integer. The higher the number, the higher the priority. All listeners with priority n are processed before listeners of priority n-1. If two or more listeners share the same priority, they are processed in the order in which they were added. The default priority is 0.
 
useWeakReference:Boolean (default = false) — Determines whether the reference to the listener is strong or weak. A strong reference (the default) prevents your listener from being garbage-collected. A weak reference does not.

Class-level member functions are not subject to garbage collection, so you can set useWeakReference to true for class-level member functions without subjecting them to garbage collection. If you set useWeakReference to true for a listener that is a nested inner function, the function will be garbage-collected and no longer persistent. If you create references to the inner function (save it in another variable) then it is not garbage-collected and stays persistent.

close

()method 
public function close():void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Closes the load operation in progress. Any load operation in progress is immediately terminated. If no URL is currently being streamed, an invalid stream error is thrown.

load

()method 
public function load(request:URLRequest):void

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Sends and loads data from the specified URL. The data can be received as text, raw binary data, or URL-encoded variables, depending on the value you set for the dataFormat property. Note that the default value of the dataFormat property is text. If you want to send data to the specified URL, you can set the data property in the URLRequest object.

Note: If a file being loaded contains non-ASCII characters (as found in many non-English languages), it is recommended that you save the file with UTF-8 or UTF-16 encoding as opposed to a non-Unicode format like ASCII.

A SWF file in the local-with-filesystem sandbox may not load data from, or provide data to, a resource that is in the network sandbox.

By default, the calling SWF file and the URL you load must be in exactly the same domain. For example, a SWF file at www.adobe.com can load data only from sources that are also at www.adobe.com. To load data from a different domain, place a URL policy file on the server hosting the data.

You cannot connect to commonly reserved ports. For a complete list of blocked ports, see "Restricting Networking APIs" in the ActionScript 3.0 Developer's Guide.

In Flash Player 10 and later, if you use a multipart Content-Type (for example "multipart/form-data") that contains an upload (indicated by a "filename" parameter in a "content-disposition" header within the POST body), the POST operation is subject to the security rules applied to uploads:

  • The POST operation must be performed in response to a user-initiated action, such as a mouse click or key press.
  • If the POST operation is cross-domain (the POST target is not on the same server as the SWF file that is sending the POST request), the target server must provide a URL policy file that permits cross-domain access.

Also, for any multipart Content-Type, the syntax must be valid (according to the RFC2046 standards). If the syntax appears to be invalid, the POST operation is subject to the security rules applied to uploads.

For more information related to security, see the Flash Player Developer Center Topic: Security.

Parameters

request:URLRequest — A URLRequest object specifying the URL to download.


Events
complete:Event — Dispatched after data has loaded successfully.
 
httpStatus:HTTPStatusEvent — If access is over HTTP, and the current Flash Player environment supports obtaining status codes, you may receive these events in addition to any complete or error event.
 
ioError:IOErrorEvent — The load operation could not be completed.
 
progress:ProgressEvent — Dispatched when data is received as the download operation progresses.
 
securityError:SecurityErrorEvent — A load operation attempted to retrieve data from a server outside the caller's security sandbox. This may be worked around using a policy file on the server.
 
securityError:SecurityErrorEvent — A load operation attempted to load a SWZ file (a Adobe platform component), but the certificate is invalid or the digest does not match the component.
 
open:Event — Dispatched when a load operation commences.
 
httpResponseStatus:HTTPStatusEvent — Dispatched if a call to the load() method attempts to access data over HTTP and Adobe AIR is able to detect and return the status code for the request.

Throws
ArgumentError URLRequest.requestHeader objects may not contain certain prohibited HTTP request headers. For more information, see the URLRequestHeader class description.
 
MemoryError — This error can occur for the following reasons: 1) Flash Player or AIR cannot convert the URLRequest.data parameter from UTF8 to MBCS. This error is applicable if the URLRequest object passed to load() is set to perform a GET operation and if System.useCodePage is set to true. 2) Flash Player or AIR cannot allocate memory for the POST data. This error is applicable if the URLRequest object passed to load is set to perform a POST operation.
 
SecurityError — Local untrusted files may not communicate with the Internet. This may be worked around by reclassifying this file as local-with-networking or trusted.
 
SecurityError — You are trying to connect to a commonly reserved port. For a complete list of blocked ports, see "Restricting Networking APIs" in the ActionScript 3.0 Developer's Guide.
 
TypeError — The value of the request parameter or the URLRequest.url property of the URLRequest object passed are null.

See also


Example  ( How to use this example )

In the following example, an XML files is loaded and the content of its elements' first arguments are displayed in a text field.

A URLRequest object is created to identify the location of the XML file, which for this example is in the same directory as the SWF file. The file is loaded in a try...catch block in order to catch any error that may occur. (Here we catch the SecurityError errors.) If an IO_ERROR event occurs, the errorHandler() method is invoked, which writes an error message in the xmlTextField text field. Once the XML file data is received and place in the data property of the loader URLLoader object, the Event.COMPLETE event is dispatched and the loaderCompleteHandler() method is invoked.

In the loaderCompleteHandler() method, a try...catch block is used to catch any parsing error that may occur while converting the loaded data from the file into an XML object. The readNodes() method then recursively goes through all the elements in the nodes of the XML document and appends the xmlTextField text field with a list of the first attributes of all the elements.

package {
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.net.URLLoader;
    import flash.net.URLRequest;
    import flash.text.TextField;
    import flash.text.TextFieldAutoSize;
    import flash.xml.*;
    import flash.events.IOErrorEvent;
  
    public class URLLoader_loadExample extends Sprite {
        private var xmlTextField:TextField = new TextField();
        private var externalXML:XML;    
        private var loader:URLLoader;

        public function URLLoader_loadExample() {
            var request:URLRequest = new URLRequest("xmlFile.xml");

            loader = new URLLoader();
            
            try {
                loader.load(request);
            }
            catch (error:SecurityError)
            {
                trace("A SecurityError has occurred.");
            }

             loader.addEventListener(IOErrorEvent.IO_ERROR, errorHandler);
            loader.addEventListener(Event.COMPLETE, loaderCompleteHandler);

            xmlTextField.x = 10;
            xmlTextField.y = 10;
            xmlTextField.background = true;
            xmlTextField.autoSize = TextFieldAutoSize.LEFT;

            addChild(xmlTextField);
        }

        private function loaderCompleteHandler(event:Event):void {

                try {
                    externalXML = new XML(loader.data);
                    readNodes(externalXML);    
                } catch (e:TypeError) {
                    trace("Could not parse the XML file.");
                }
        }

        private function readNodes(node:XML):void {

                for each (var element:XML in node.elements()) {
                    xmlTextField.appendText(element.attributes()[0] + "\n");

                    readNodes(element);
                }    
        }

        private function errorHandler(e:IOErrorEvent):void {
            xmlTextField.text = "Had problem loading the XML File.";
        }
    }
}
Event Detail

complete

Event
Event Object Type: flash.events.Event
property Event.type = flash.events.Event.COMPLETE

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Dispatched after all the received data is decoded and placed in the data property of the URLLoader object. The received data may be accessed once this event has been dispatched.

The Event.COMPLETE constant defines the value of the type property of a complete event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe network object that has completed loading.

See also

AIR-only 

httpResponseStatus

Event  
Event Object Type: flash.events.HTTPStatusEvent
property HTTPStatusEvent.type = flash.events.HTTPStatusEvent.HTTP_RESPONSE_STATUS

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, AIR 1.0, Flash Lite 4

Dispatched if a call to the load() method attempts to access data over HTTP, and Adobe AIR is able to detect and return the status code for the request.

Unlike the httpStatus event, the httpResponseStatus event is delivered before any response data. Also, the httpResponseStatus event includes values for the responseHeaders and responseURL properties (which are undefined for an httpStatus event. Note that the httpResponseStatus event (if any) will be sent before (and in addition to) any complete or error event.

The HTTPStatusEvent.HTTP_RESPONSE_STATUS constant defines the value of the type property of a httpResponseStatus event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
responseURLThe URL from which the response was returned.
responseHeadersThe response headers that the response returned, as an array of URLRequestHeader objects.
statusThe HTTP status code returned by the server.
targetThe network object receiving an HTTP status code.

See also

httpStatus

Event  
Event Object Type: flash.events.HTTPStatusEvent
property HTTPStatusEvent.type = flash.events.HTTPStatusEvent.HTTP_STATUS

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Dispatched if a call to URLLoader.load() attempts to access data over HTTP. For content running in Flash Player, this event is only dispatched if the current Flash Player environment is able to detect and return the status code for the request. (Some browser environments may not be able to provide this information.) Note that the httpStatus event (if any) is sent before (and in addition to) any complete or error event.

The HTTPStatusEvent.HTTP_STATUS constant defines the value of the type property of a httpStatus event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
statusThe HTTP status code returned by the server.
targetThe network object receiving an HTTP status code.

See also

ioError

Event  
Event Object Type: flash.events.IOErrorEvent
property IOErrorEvent.type = flash.events.IOErrorEvent.IO_ERROR

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Dispatched if a call to URLLoader.load() results in a fatal error that terminates the download.

Defines the value of the type property of an ioError event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
errorIDA reference number associated with the specific error (AIR only).
targetThe network object experiencing the input/output error.
textText to be displayed as an error message.

See also

open

Event  
Event Object Type: flash.events.Event
property Event.type = flash.events.Event.OPEN

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Dispatched when the download operation commences following a call to the URLLoader.load() method.

The Event.OPEN constant defines the value of the type property of an open event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe network object that has opened a connection.

See also

progress

Event  
Event Object Type: flash.events.ProgressEvent
property ProgressEvent.type = flash.events.ProgressEvent.PROGRESS

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Dispatched when data is received as the download operation progresses.

Note that with a URLLoader object, it is not possible to access the data until it has been received completely. So, the progress event only serves as a notification of how far the download has progressed. To access the data before it's entirely downloaded, use a URLStream object.

Defines the value of the type property of a progress event object.

This event has the following properties:

PropertyValue
bubblesfalse
bytesLoadedThe number of items or bytes loaded at the time the listener processes the event.
bytesTotalThe total number of items or bytes that ultimately will be loaded if the loading process succeeds.
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe object reporting progress.

See also

securityError

Event  
Event Object Type: flash.events.SecurityErrorEvent
property SecurityErrorEvent.type = flash.events.SecurityErrorEvent.SECURITY_ERROR

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9, Flash Lite 4

Dispatched if a call to URLLoader.load() attempts to load data from a server outside the security sandbox. Also dispatched if a call to URLLoader.load() attempts to load a SWZ file and the certificate is invalid or the digest string does not match the component.

The SecurityErrorEvent.SECURITY_ERROR constant defines the value of the type property of a securityError event object.

This event has the following properties:

PropertyValue
bubblesfalse
cancelablefalse; there is no default behavior to cancel.
currentTargetThe object that is actively processing the Event object with an event listener.
targetThe network object reporting the security error.
textText to be displayed as an error message.

See also

URLLoaderExample.as

The following example loads and displays the data found in a local text file. It also traces event handling information.

Note: To run this example, put a file named urlLoaderExample.txt in the same directory as your SWF file. That file should only contain the following line of text: answer=42&question=unknown

The example code does the following:

  1. The constructor function creates a URLLoader instance named loader and a URLRequest instance named request, which contains the location and name of the file to be loaded.
  2. The loader object is passed to the configureListeners() method, which adds listeners for each of the supported URLLoader events.
  3. The request object is then passed to loader.load(), which loads the text file.
  4. When the URLLoader has finished loading the text file the Event.COMPLETE event fires, triggering the completeHandler() method. The completeHandler() method creates a URLVariables object from the text loaded from the file. The URLVariables object converts URL-encoded name/value pairs into ActionScript properties to make it easier to manipulate the loaded data.

package {
    import flash.display.Sprite;
    import flash.events.*;
    import flash.net.*;

    public class URLLoaderExample extends Sprite {
        public function URLLoaderExample() {
            var loader:URLLoader = new URLLoader();
            configureListeners(loader);

            var request:URLRequest = new URLRequest("urlLoaderExample.txt");
            try {
                loader.load(request);
            } catch (error:Error) {
                trace("Unable to load requested document.");
            }
        }

        private function configureListeners(dispatcher:IEventDispatcher):void {
            dispatcher.addEventListener(Event.COMPLETE, completeHandler);
            dispatcher.addEventListener(Event.OPEN, openHandler);
            dispatcher.addEventListener(ProgressEvent.PROGRESS, progressHandler);
            dispatcher.addEventListener(SecurityErrorEvent.SECURITY_ERROR, securityErrorHandler);
            dispatcher.addEventListener(HTTPStatusEvent.HTTP_STATUS, httpStatusHandler);
            dispatcher.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
        }

        private function completeHandler(event:Event):void {
            var loader:URLLoader = URLLoader(event.target);
            trace("completeHandler: " + loader.data);
    
            var vars:URLVariables = new URLVariables(loader.data);
            trace("The answer is " + vars.answer);
        }

        private function openHandler(event:Event):void {
            trace("openHandler: " + event);
        }

        private function progressHandler(event:ProgressEvent):void {
            trace("progressHandler loaded:" + event.bytesLoaded + " total: " + event.bytesTotal);
        }

        private function securityErrorHandler(event:SecurityErrorEvent):void {
            trace("securityErrorHandler: " + event);
        }

        private function httpStatusHandler(event:HTTPStatusEvent):void {
            trace("httpStatusHandler: " + event);
        }

        private function ioErrorHandler(event:IOErrorEvent):void {
            trace("ioErrorHandler: " + event);
        }
    }
}