How to remove all of one class of children from screen in Flash CS4 AS3? - actionscript-3

Question

Ok, so I've been stuck on this for about three hours now and I finally feel like asking for help.
Basically, I am trying to remove all instances of an enemy object from the screen when my player ship makes contact with one of them, as he then loses a life and is put back into a safe position on the screen.
EDIT: This is all the code from my Enemy Dude .as file, a bit overboard maybe but nonetheless.
package
{
import flash.display.MovieClip;
import flash.events.*;
import flash.media.Sound;
import flash.media.SoundChannel;
public class Enemydude extends MovieClip
{
private var _root:Object;
private var speed:int = 6;
private var shipps = this
public function Enemydude()
{
addEventListener(Event.ADDED, beginclass);
addEventListener(Event.ENTER_FRAME, entFrame);
}
private function beginclass(event:Event):void
{
_root = MovieClip(root);
}
private function entFrame(event:Event):void
{
x -= speed;
if(this.x < -64)
{
removeEventListener(Event.ENTER_FRAME, entFrame);
_root.removeChild(this)
}
if(_root.gameover)
{
x = -700
removeEventListener(Event.ENTER_FRAME, entFrame);
removeEventListener(Event.ADDED, beginclass);
}
for (var i:int = 0; i<_root.playerBulletContainer.numChildren; i++)
{
var bulletTarget:MovieClip = _root.playerBulletContainer.getChildAt(i)
if (hitTestObject(bulletTarget))
{
removeEventListener(Event.ENTER_FRAME, entFrame);
_root.removeChild(this);
_root.playerBulletContainer.removeChild(bulletTarget);
bulletTarget.removeListeners();
_root.Score += 10
makeExplosion();
}
}
if(hitTestObject(_root.mcship))
{
makeExplosion();
shipPos();
removethis();
}
}
private function makeExplosion()
{
var sndExplode:snd_explosion1;
var sndExplodeChannel:SoundChannel;
sndExplode=new snd_explosion1();
sndExplodeChannel=sndExplode.play();
var newExplosion01:explosionEffect=new explosionEffect ;
newExplosion01.x=this.x;
newExplosion01.y=this.y;
_root.explosionContainer.addChild(newExplosion01);
}
private function shipPos()
{
_root.lives -= 1;
_root.mcship.x = 80;
_root.mcship.y = 225;
for each(var i:Enemydude in _root.enemies)
{
removethis();
}
_root.enemies.length = 0;
}
public function removethis():void
{
if(parent) parent.removeChild(this)
removeEventListener(Event.ENTER_FRAME, entFrame);
}
}
}
EDIT: And this is the code I now have that relates to the Enemydude in my main timeline, quite sorry about all this.
var enemies:Array = [];
var Shipheight:Number = 300;
var Enemytime:int = 0;
var Enemylimit:int = 16;
if (Enemytime<Enemylimit)
{
Enemytime ++;
}
else
{
var newEnemy01 = new Enemydude();
newEnemy01.y = Shipheight;
newEnemy01.x = stage.stageWidth + 64;
addChild(newEnemy01);
enemies.push(newEnemy01);
Enemytime = 0
function shipY(event:Event):void
{
Shipheight = Math.ceil(Math.random()* 250) + 80;
}
Thank you for your help in advance, any advice is appreciated.

Answer 1

I suggest storing your enemies in an Array.
For example, create the array enemies:
var enemies:Array = [];
And then amend your code to:
else
{
var newEnemy01 = new Enemydude();
newEnemy01.y = Shipheight;
newEnemy01.x = stage.stageWidth + 64;
addChild(newEnemy01);
enemies.push(newEnemy01);
Enemytime = 0;
}
That way you can remove all of the enemies using this new array:
for each(var i:Enemydude in enemies)
{
i.remove(); // Or whatever function Enemydude has to remove itself.
}
// Empty the enemies Array.
enemies.length = 0;
Here's the .remove() method you could make for Enemydude:
public function remove():void
{
if(parent) parent.removeChild(this);
// Remove any event listeners etc from this object.
}

Answer 2

A common and easy way of doing this is to create a subcontainer to hold the objects and destroy this object instead. It makes easy for some collision checks too, since you can use the holder object to make one check against the player.
If you don't want to create this, you can use an array or a vector to store references to this objects, what makes easy to traverse the list.
I persoally recommend the vector aprouch:
var enemyList:Vector.<Enemy> = new Vector.<Enemy>();
Then you can loop almost like an array (as Marty Wallace showed on his answer):
for each(var e:Enemy in enemyList) {
container.removeChild(e);
}
enemyList.length = 0; // empty vector
Vectors are a bit slower than normal arrays, but are type safe. The difference in performance is almost negligible in most cases.