addChild and removeChild with MouseEvent

programming flash
1

[COLOR=#000000]Hello, I am a newby at AS3. I need help with addChild and removeChild.
I want to make a two buttons one addChild and other removeChild . Friend helped me a little bit, but I didnt uderstand the script ;]
Here is the example script which my friend gave to me. In other words I want to make a button that attached hair and the other that removes.
Should I make a separete custom class for Hair? And if do, can someone help? :]

public function changeHairs(newHair:Hair):Hair
{
Face.removeChild(oldHairs);
oldHairs = newHair;
Face.addChild(newHair);

		return newHair;
	}

Or modify this code

package {

import flash.display.MovieClip;

[/COLOR][COLOR=#000000] import Button;[/COLOR][COLOR=#000000]
import flash.text.TextField;
import flash.events.MouseEvent;

public class Faces2 extends MovieClip 
{
	public var arr:Array = new Array(a1,a2,a3);
	trace("aab");
	public var txt:TextField = new TextField()
	public var btnBack:Button = new Button();
	public var btnFwd:Button = new Button();
	
	public var arrPos:Number = 0;
	
	public function Faces2() 
	{
		setupInterface();
		setupData(arrPos);
	}
	
	public function setupInterface():void
	{
		btnBack.x = 100; btnBack.y = 10;
		btnFwd.x = 200; btnFwd.y = 10;
		
		btnBack.addEventListener(MouseEvent.CLICK, back);
		btnFwd.addEventListener(MouseEvent.CLICK, fwd);
		
		addChild(btnBack); 
		addChild(btnFwd);
		
		txt.textColor = 0xFF0000;
		txt.width = 300;
		txt.border = true;
		txt.x = 100; txt.y = 100;
		
		addChild(txt)
	}
	
	public function fwd(evt:MouseEvent):void
	{
		arrPos ++;
		if(arrPos >= arr.length) 
		{
			arrPos = 0;
		}
		setupData(arrPos); 
	}
	
	public function back(evt:MouseEvent):void
	{
		arrPos --;
		if(arrPos < 0) 
		{
			arrPos = arr.length - 1;
		}
		setupData(arrPos);
	}
	
	public function setupData(pos:Number):void
	{
		txt.text = arr[pos];
	}

[/COLOR][COLOR=#000000] }[/COLOR][COLOR=#000000]

}

P.S. sorry for my english

[COLOR=#000000][/COLOR]
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