Returning a string in Action Script 3.0 - actionscript-3

Question

I'm really not familiar with Action Script 3 at all but I am with other languages.
I'm hoping someone could help me.
I'm attempting to make a modification to JWplayer so that an rtmp stream is retrieved via a PHP script rather than it being supplied in the HTML.
The code I currently have is below:
function useData(event:Event):void {
var data:String = event.target.data.toString();
}
/** Load content. **/
override public function load(itm:PlaylistItem):void {
_item = itm;
_position = 0;
var loader:URLLoader = new URLLoader();
loader.addEventListener(Event.COMPLETE, useData);
loader.load(new URLRequest("http://192.168.0.12/phpauth/play1.php"));
// Set Video or StageVideo
if(!_video) {
_video = new Video(320, 240);
_video.smoothing = true;
_video.addEventListener('renderState', renderHandler);
// Use stageVideo when available
if (_stageEnabled && RootReference.stage['stageVideos'].length > 0) {
_stage = RootReference.stage['stageVideos'][0];
_stage.viewPort = new Rectangle(0,0,320,240);
_stage.addEventListener('renderState', renderHandler);
}
attachNetStream(_stream);
}
// Load either file, streamer or manifest
if (_item.file.substr(0,4) == 'rtmp') {
// Split application and stream
var definst:Number = _item.file.indexOf('_definst_');
In the load function the file name to play is held in _item.file. I'm trying to make a call to a php script which then overwrites the value in _item.file. I've confirmed that the php is being called but I don't know how to get the data from the data string in the useData function into the _item.file string.
Any help would be really appreciated - I suspect this is a simple one but my lack of AS3 knowledge is making it really difficult.
Thanks,

Answer 1

Your problem basically about how to access a local variable in an event handler. A quick and dirty way can be to have an anonymous function used as a handler like:
loader.addEventListener(Event.COMPLETE, function(event:Event):void {
var data:String = event.target.data.toString();
_item.file = data;
});
This approach would work, because this anonymous function has access to the local variables inside load function as is. But, you need to be cautious that the anonymous function uses the variable exactly as the calling function is using. So, let's say there is a loop in load function and _item changes in every iteration of the loop. For that scenario, when load handler gets called, its _item would also have changed to the object which was last assigned to _item.
A far cleaner and OO approach can be to have a handler class like:
package {
public class LoadHandler {
private var _item:PlaylistItem;
public function LoadHandler(item:PlaylistItem) {
_item = item;
}
public function loadHandler(event:Event):void {
var data:String = event.target.data.toString();
_item.file = data;
}
}
and then have loader.addEventListener(Event.COMPLETE, (new LoadHandler(_item)).loadHandler). Hope that helps. BTW, LoadHandler could be made more generic to take and array of objects to be used and a callback function. loadHandler function, then could just call callback function with that array of objects.

Answer 2

If you are returning a simple string from PHP you should be able to use
event.target.data;
e.g. from PHP... echo "hello";
var data:String = event.target.data
You could try tracing the response to ensure you are getting something back from PHP.
You can either test this from within the IDE or install the Debug version of the Flash Player browser plugin.
trace("Response from PHP: "+event.target.data);
_item.file = event.target.data;
trace("_item.file: "+_item.file);