External ActionScript Only Executed When Testing Single Scene - actionscript-3

Question

New to AS 3.0 and I seem to have an issue where an external AS file is run when I test an individual scene in Flash Pro but not when I test the entire movie or when I test from Flash Builder. Anyone know what the problem might be?
Here's the code from the AS file:
package {
import flash.display.MovieClip;
public class Level1 extends MovieClip {
public var myplayer:MyPlayer;
public function Level1() {
super();
myplayer.x = 516;
myplayer.y = 371;
if (myplayer.x == 516)
{
trace("player x is 516");
}
else if (myplayer.y == 371)
{
trace("player y is 371");
}
}
}
}
Any ideas?
EDIT
I think I figured out the problem. The swf contained two scenes, and the external AS file started running at the start of Scene 1, but the myPlayer movie clip was not instantiated until Scene2, which, I think was causing the problem I was having, in addition to giving a 1009 null object error.
So I simply deleted the first scene, and now everything works fine. Maybe I will put that first scene in a separate SWF? Or, is there some way to delay a script's execution until a certain scene?

Answer 1

Your problem:
When the constructor of your doucment class runs, myPlayer doesn't yet exist so it throws a 1009 runtime error and exits the constructor at the first reference to myPlayer.
Solutions:
Put all the myPlayer code on the first frame of the MyPlayer timeline. OR use your current document class as the class file for MyPlayer (instead of documentClass). Change all references to myPlayer to this.
Listen for frame changes and check until myPlayer is populated, then run your code.
this.addEventListener(Event.ENTER_FRAME, enterFrameHandler);
function enterFrameHandler(e):void {
if(myPlayer){
//run the myPlayer code
this.removeEventListener(Event.ENTER_FRAME,enterFrameHandler);
}
}
If your frame rate is 24fps, this code though will run 24 times every second (until it finds myPlayer), so it's not the most performant way to go.
Use events. Add an event to the first frame of myPlayer (or to a class file for MyPLayer) that tells the document class that it exists now.
stage.dispatchEvent(new Event("myPlayerReady"));
Then listen for that event on the document class:
stage.addEventListener("myPlayerReady",playerReadyHandler);
playerReadyHandler(e:Event):void {
//your player code
var myPlayer = MyPlayer(e.target); //you can even get the reference from the event object
}

Answer 2

Thanks for your constructive, helpful responses, LDMS. I thought I had found a solution when I hadn't. Your advice worked. What I did was add the following code to the timeline of MyPlayer
this.x = 516;
this.y = 371;
if (this.x == 516)
{
trace("player x is 516");
}
if (this.y == 371)
{
trace("player y is 371");
}
and I removed the code from the document class. Everything seems to be working fine now. Thanks again for your help!