Solved

the as3 code for the frame still runs even after I delete the child it is in...

Posted on 2008-10-27
5
620 Views
Last Modified: 2012-08-14
I'm making a game where after you shoot a bullet, the bullet destroys itself at the end of its timeline.  There is also an event on the main stage that resets the game by deleting all the objects, but if the game gets reset while a bullet is on the self destruct frame, it produces an error, because apparently even after the bullet has been destroyed, the code telling it to destory itself still runs, but it can't destroy itself because it no longer exists!!  How can I fix this!


Below I have created a simplified version of my problem as an example so you can see it in action for yourself.

//This Code is in the first frame of the stage root.      
while (numChildren!=0)
   {
trace(this.numChildren+ " stage children.")
removeChildAt(this.numChildren-1);
      }
      trace(this.numChildren+ " stage children after deleting them all.")
      stop();



------------------------------------------


//On the stage are 4 MovieClip instances of "TestBox",  "TestBox" has this code in the second frame.
MovieClip(parent).removeChild(this);
stop();



WHEN I RUN IT, THIS IS THE OUTPUT.
4 stage children.
3 stage children.
2 stage children.
1 stage children.
0 stage children after deleting them all.
TypeError: Error #1009: Cannot access a property or method of a null object reference.
      at test_fla::TestBox_1/test_fla::frame2()
TypeError: Error #1009: Cannot access a property or method of a null object reference.
      at test_fla::TestBox_1/test_fla::frame2()
TypeError: Error #1009: Cannot access a property or method of a null object reference.
      at test_fla::TestBox_1/test_fla::frame2()
TypeError: Error #1009: Cannot access a property or method of a null object reference.
      at test_fla::TestBox_1/test_fla::frame2()

0
Comment
Question by:cakepizza
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
5 Comments
 
LVL 34

Expert Comment

by:Aneesh Chopra
ID: 22828669
I recommend to attach your source files for review, this will help to provide the quicker solution
0
 

Author Comment

by:cakepizza
ID: 22832916
ok, I have attached a small  fla file that basically is just the example code I posted above.  It would not let me attach an fla file though, even in a zip folder, so I changed the file extension to .bmp.  Just rename it back to .fla and check it out.

  The goal is to get the first frame to REALLY delete the 4 boxes, so that their action script (which references themselves) will not run, because when the action script in the boxes run, it causes an error, since they are referencing themselves, which are supposed to no longer exist.
test.bmp
0
 
LVL 34

Accepted Solution

by:
Aneesh Chopra earned 500 total points
ID: 22833893
there are many forum/blog mentioned similar issue without any sureshot solution..
hence,
here is the updated code which is actually workaround for your issue:


var total = this.numChildren;
for (var i=total-1; i>=0; i--) {
	trace(this.numChildren+ " stage children.");
	var mc = getChildAt(i);
	mc.stop();
	removeChild(mc);
	mc = null;
}
//
trace(this.numChildren+ " stage children after deleting them all.");
stop();

Open in new window

0
 
LVL 39

Expert Comment

by:blue-genie
ID: 22842254
hello.
just wondering -  the fact that on the maintimeline you're removing all the children, then in frame 2 of the children, you're saying remove this, but they're removed so you get a null reference?
0
 

Author Comment

by:cakepizza
ID: 22849330
yes.  The action script for the second frame of the children should not be running, because they are children that have been removed already.  Looking at the solution, it seems that simply removing children is not enough to actually get rid of them.  You also have to stop their timeline and set them to null manually.
0

Featured Post

Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I know the transition can be hard. We got used to the ease of use ActionScript 2 had, but honestly, it became problematic later on, especially if designers were involved in the project and found it easy to add code as they saw fit. So, this artic…
Here are some practices and techniques that can be adopted into your Flash/Flex application development process. Note: Not all "performance tips" provide an immediately-recognizable benefit.   This article does not include timing validation data,…
The goal of the tutorial is to teach the user how to set there setting in Adobe Flash Media Live Encoder and YouTube for optimal video and audio quality.
This Micro Tutorial will teach to how to utilize bit rate in Adobe Flash Media Live Encoder.

691 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question