Is anyone interested in looking at my code for a game? I'm getting strange errors - actionscript-3

Question

I'm trying to make my first real, simple shooter game. I've read through tutorials online and instead of directly copying code, I tried to take things the next level to actually understand the code and add my own twists. With this in mind, I've recently been learning arrays and not sure if I am using them correctly.
I'm getting strange, intermittent
Error #2025 DisplayObject must be a child of the caller
messages in the output window, not the compiler window.
So, I don't know what line of code is generating this problem. By commenting out blocks of code I have narrowed it down to the modules labeled "CLEANUP MISSED ENEMIES" and "BULLET RATE OF SHOOTING", but the 'why' is beyond my understanding.
I am sure there will be many great comments pointing out conventions I get wrong and errors I am making. I value every chance to learn so please give your input as you see fit! I bet there are way better methods to do the things I am doing!
package{
import flash.events.Event;
import flash.display.MovieClip;
import flash.media.Sound;
import flash.media.SoundChannel;
import com.greensock.*;
import com.greensock.easing.*;
import flash.events.MouseEvent;
import flash.events.KeyboardEvent;
import flash.utils.Timer;
import flash.events.TimerEvent;
import flash.geom.ColorTransform;
import fl.motion.Color;
import flash.display.DisplayObject;
public class chopper extends MovieClip{
public function chopper(){
boot();
}
public function boot():void{
/////////VARS
var coptr:MovieClip = new copter();
var bulit:MovieClip = new bullit();
var mouseIsDn = false;
var speed = 0;
var PEW = false
var meter:MovieClip = new meters();
var bltArray:Array = new Array();
var airArray:Array = new Array();
var gndArray:Array = new Array();
var gameTIMERa:Timer = new Timer(5000);
var gameTIMERb:Timer = new Timer(10000);
stage.addEventListener(MouseEvent.MOUSE_DOWN, clicked);
stage.addEventListener(MouseEvent.MOUSE_UP, unclicked);
function clicked(e:Event):void{
mouseIsDn = true;
}
function unclicked(e:Event):void{
mouseIsDn = false;
}
/////////INTRO SCREEN
var titl:MovieClip = new title();
addChild(titl);
var strt:MovieClip = new start();
addChild(strt);
var govr:MovieClip = new gOVER();
var ctINTRO:Color = new Color();
ctINTRO.setTint(Math.random()*0xFFFFFF, 0.5);
BG.transform.colorTransform = ctINTRO;
/////////MUSIC
var ChanAB:SoundChannel = new SoundChannel();
var Amusic:Sound = new musicA();
var Bmusic:Sound = new musicB();
ChanAB = Amusic.play(0, 9999);
/////////SFx
var ChanSFx:SoundChannel = new SoundChannel();
var Ashoot:Sound = new shootA();
var SFx:Array = new Array();
var Asuck:Sound = new suckA();
SFx.push(Asuck);
var Bsuck:Sound = new suckB();
SFx.push(Bsuck);
var Csuck:Sound = new suckC();
SFx.push(Csuck);
var gOver:Sound = new over();
/////////START
strt.startBTN.addEventListener(MouseEvent.CLICK, str);
function str(e:Event):void{
removeChild(titl);
removeChild(strt);
ChanAB.stop();
BG.transform.colorTransform = new ColorTransform;
////////////
ChanAB = Bmusic.play(0, 9999);
addChild(coptr);
TweenLite.to(coptr, 3, {x:157, y:316});
addChild(meter);
meter.x = 861;
meter.y = 9;
TweenLite.to(meter, 1, {x:735});
meter.life.gotoAndPlay(2);
gameTIMERa.addEventListener(TimerEvent.TIMER, addAIR);
gameTIMERa.start();
gameTIMERb.addEventListener(TimerEvent.TIMER, addGND);
gameTIMERb.start();
}
/////////ADDING ENEMIES
function addAIR(e:TimerEvent):void{
var Aair:MovieClip = new airA();
Aair.x = 805;
Aair.scaleX = .25
Aair.y = Math.random() * stage.stageHeight - Aair.height;
Aair.scaleY = .25
airArray.push(Aair);
addChild(Aair);
}
function addGND(e:TimerEvent):void{
var Agnd:MovieClip = new gndA();
Agnd.x = 805;
Agnd.scaleX = .25
Agnd.y = 430 + Math.floor(Math.random() * 36);
Agnd.scaleY = .25
gndArray.push(Agnd);
addChild(Agnd);
}
addEventListener(Event.ENTER_FRAME, startLoop);
function startLoop(e:Event):void{
if(coptr.x == 157 && coptr.y == 316){
speed = 10;
meter.life.gotoAndStop(10);
removeEventListener(Event.ENTER_FRAME, startLoop);
addEventListener(Event.ENTER_FRAME, gameLoop);
stage.addEventListener(KeyboardEvent.KEY_DOWN, shoot);
}
}
/////////COPTER SHOOTING
function shoot(e:Event):void{
if(PEW == false){
ChanSFx = Ashoot.play();
bulit.x = coptr.x + 5;
bulit.y = coptr.y;
bltArray.push(bulit);
addChild(bulit);
PEW = true;
}
}
/////////LIFE METER
function lifeMeterA(e:Event = null):void{
if(meter.life.width > 59){
meter.life.scaleX -= .04;
}
else if(meter.life.width < 59 && meter.life.width > 29){
meter.life.gotoAndStop(11);
meter.life.scaleX -= .04;
}
else if(meter.life.width < 29 && meter.life.width > 15){
meter.life.gotoAndStop(12)
meter.life.scaleX -= .04;
}
else if(meter.life.width < 15 && meter.life.width > 1.5){
meter.life.gotoAndPlay(2);
meter.life.scaleX -= .04;
}
}
function lifeMeterB(e:Event = null):void{
if(meter.life.width > 59){
meter.life.scaleX -= .01;
}
else if(meter.life.width < 59 && meter.life.width > 29){
meter.life.gotoAndStop(11);
meter.life.scaleX -= .01;
}
else if(meter.life.width < 29 && meter.life.width > 15){
meter.life.gotoAndStop(12)
meter.life.scaleX -= .01;
}
else if(meter.life.width < 15 && meter.life.width > 1.5){
meter.life.gotoAndPlay(2);
meter.life.scaleX -= .01;
}
}
////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////MAIN LOOP
function gameLoop(e:Event) {
////////////////////////COPTER MOVEMENT
trace(bltArray);
trace(airArray);
trace(gndArray);
coptr.y += speed;
if(mouseIsDn){
if(speed > -5){
speed -= 1;
}
}else{
if(speed < 10){
speed += .25;
}
}
////////////////////////BULLET MOVEMENT
if(bulit){
bulit.x += 10;
}
if(coptr.y > stage.stageHeight - coptr.height*.5){
coptr.y = stage.stageHeight - coptr.height*.5;
}
else if(coptr.y < 0 + coptr.height*.5){
coptr.y = 0 + coptr.height*.5;
}
////////////////////////COLLISIONS
for(var i = 0; i<numChildren; i++){
if(getChildAt(i) is airA){
var b = getChildAt(i) as airA;
if(b.hitTestObject(coptr)){
lifeMeterA();
}
if(b.hitTestObject(bulit)){
airArray.shift();
removeChild(b);
removeChild(bltArray[0]);
PEW = false;
var m:uint = uint(Math.random() * 3);
ChanSFx = SFx[m].play();
}
}
else if(getChildAt(i) is gndA){
var c = getChildAt(i) as gndA;
if(c.hitTestObject(coptr)){
lifeMeterB();
}
if(c.hitTestObject(bulit)){
gndArray.shift();
removeChild(c);
removeChild(bltArray[0]);
PEW = false;
var n:uint = uint(Math.random() * 3);
ChanSFx = SFx[n].play();
}
}
}
if(coptr.y > stage.stageHeight - coptr.height){
lifeMeterA();
}
////////////////////////CLEANUP MISSED ENEMIES
if(airArray[0] && airArray[0].x < 0){
airArray.shift();
}
if(gndArray[0] && gndArray[0].x < 0){
gndArray.shift();
}
////////////////////////BULLET RATE OF SHOOTING
if(bltArray[0] && bltArray[0].x > stage.stageWidth){
PEW = false;
bltArray.shift();
}
////////////////////////END GAME
if(meter.life.width < 1.5){
removeEventListener(Event.ENTER_FRAME, gameLoop);
gameTIMERa.stop();
gameTIMERb.stop();
meter.life.gotoAndStop(13);
TweenLite.to(meter, .5, {x:861});
gameO();
}
}
function gameO(e:Event = null):void{
addChild(govr);
govr.x = 0;
govr.y = 0;
ChanAB.stop();
ChanSFx = gOver.play();
ChanSFx.addEventListener(Event.SOUND_COMPLETE, restart);
}
function restart(e:Event):void{
removeChild(govr);
removeChild(coptr);
boot();
}
}
}
}
Thanks in advance!

Answer 1

It means you're using removeChild() somewhere on an object whose parent is not the container you are trying to remove it from.
For example, this code would cause that error:
var shape:Shape = new Shape();
stage.removeChild(shape);
It's likely that you are calling removeChild() more than once somewhere in your code.