AS3：从外部加载的SWF获取信息

Question

So I have an SWF that I've made and I need to appened some instructions to the beginning of the project. I figured the easiest way to do this was to make the animation in a separate SWF then import it to the start of the first one. My problem is that I can't find a reliable way to tell when the first SWF is finished playing. I've googled the heck out of this but I can't seem to find anything that works. For some bizarre reason, no matter what I do the program seems to think that the external SWF only has 2 frames, if I put an ENTER_FRAME listener and trace externalSWF.currentFrame I get "1, 1, 2, 2, 2, 2, 2, 2..." My code looks something like this.

var ldr = new Loader();
ldr.contentLoaderInfo.addEventListener(Event.COMPLETE, loaded);
ldr.load(new URLRequest("Instructions.swf"));

function loaded(e:Event){
    trace("Loaded");
    var extSwf = ldr.content as MovieClip;
    addChild(extSwf);
    trace(extSwf.totalFrames);//Returns 2
}

Has anyone else had similar problems with external SWFs?

Also, for the record, the external SWF plays properly when I add it as a child. The problem is removing it from the stage when it's done playing. It's interactive so I can't just do a frame count.

Edit: So I tried doing a getQualifiedClassName() call on extSwf and I got "Instructions_fla::MainTimeline_ Preloader _" which could explain the frame discrepency. How can I have access to the actual timeline?

Answer 1

To SWFs can communicate with each other via SharedObject.

http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/net/SharedObject.html

Answer 2

So I found the solution to the problem. Like I said in the edit, I was getting "Instructions_fla::MainTimeline_Preloader_" as the QualifiedClassName so I googled that and found someone saying that Flash CS5 exports your SWFs with a preloader by default so that was what was being attached to extSwf and not the MovieClip itself. The way to fix it is to go into File>Actionscript Settings>Library Path, and change Default linkage to "Merged Into Code". This appears to only happen in CS5. I found the solution here: http://blog.flash-core.com/?p=142