event listener not listening very well

#1 (**permalink**) 08-15-2008, 05:43 PM

HI, I am having problems with getting an eventListener to work properly.
Right now I have 3 functions, one to loop through data and add the data to an
arrayCollection, one to create a loader object and a third that is a
completeHandler for the loader. There is an event listener function in the
loader function that was working without the loop, now however it is not. To
simplify the posted code my loop handler etc is stripped down to remove
declarations. Any help is appreciated. Thank You.

private function loop(e:MouseEvent):void
{
for (i:int = 0; i< array.length; i++){
loadImage(fileURL);
//***** it should wait here until the loader is done loading
ac.addItemAt(image, i);
}}

private function loadImage(url:String):void
{
var request:URLRequest = new URLRequest(url);
var imageLoader:Loader = new Loader();

//***** here is the event listener that worked before adding the loop

imageLoader.contentLoaderInfo.addEventListener
(Event.COMPLETE, loadComplete);
imageLoader.load(request);
}

private function loadComplete(event:Event):void
{
var bitMap:Bitmap = new Bitmap(event.currentTarget.content.bitmapData);
var bmd:BitmapData = bitMap.bitmapData;
image = new BitmapData(bitMap.width, bitMap.height, true);
image.draw(bitMap);
}

#2 (**permalink**) 08-15-2008, 06:17 PM

This no doubt has to do with the fact that Flex is asynchronous. I would have the ac.addItemAt(image, i) in the loadComplete method.

#3 (**permalink**) 08-15-2008, 10:04 PM

Greg, good idea, but I tried that also. Unfortunately, when I do add the
ac.addItemAt(image, i) into the loadComplete function it errors out of bounds
because the .load call loads each of the files in succession without waiting
for the loader to be done each time. So I get one instance of the array, but
not all 5. So then I tried making the counter a module level variable and
adding an if statement to the loadComplete function to check and see if the i
value was less than the array.length of my input array and unfortunately that
didn't work either.

I am just learning this language, but there seems to have to be a way to deal
with these instances. I don't know all the tools available but one that seems
promising is the following:
create an event
var e:Event = new Event("watchTheStupidLoader");

take out the loop completely and check the counter with a function;
change the location of the array[i] and increment the counter within that
function, passing the next url as a return. I guess it would be a way to
post-test the loop...

any comment on trying it that way or a tool I'm overlooking?

#4 (**permalink**) 08-15-2008, 10:04 PM

Your approach seems reasonable.

#5 (**permalink**) 08-19-2008, 09:43 PM

I just thought I'd give a follow up on how I figured out this problem. Of
course, this may not be the best solution, so if anyone wants to chime in and
tell me how it should be done, please by all means... :beer;

I removed the loop completely and rewrote the loadImage function with a new
progressEvent handler. And as Greg suggested added the ac.adItem() call to the
loadComplete function.

private function loadImage(url:String):void{
var request:URLRequest = new URLRequest(url);
var imageLoader:Loader = new Loader();
imageLoader.contentLoaderInfo.addEventListener(Eve nt.COMPLETE, loadComplete);
imageLoader.contentLoaderInfo.addEventListener(Pro gressEvent.PROGRESS,
pullNextImage);
imageLoader.load(request);
}//end loadImage

private function loadComplete(event:Event):void{
trace("loadImage function sucessfully completed");
var bitMap:Bitmap = new Bitmap(event.currentTarget.content.bitmapData);
var bmd:BitmapData = bitMap.bitmapData;
image = new BitmapData(bitMap.width, bitMap.height, true);
image.draw(bitMap);
ac.addItem({image:image, label:"item #" + (ac.length + 1)});
txtLoad.text= "Image " + photoListString +" loaded successfully";
ac.refresh();
}//end loadComplete

private function pullNextImage(event:ProgressEvent):void{
trace("progress event complete");
i++;
if (i<j){
loadImage(photoList[i]);
}
}//end pullNextImage