Animating with a for loop part 2 - actionscript-3

Question

I have another question thats has been bugging me. It's kinda a follow up from my other question "Animating with a for loop?" Ok so I have that down, but how could I animate each ball to go randomly around the stage and not follow each other?
Here is my code:
ball is pulled from an external class named Ball.
package
{
import flash.display.Sprite;
import flash.events.Event;
import flash.events.KeyboardEvent;
import flash.text.TextField;
import flash.ui.Keyboard;
public class Dummy extends Sprite
{
private var balls:Array;
private var ball:Ball;
private var ballNum: Number = 10;
private var ax:Number = 4;
public function Dummy()
{
init();
}
private function init():void
{
balls = new Array();
for(var i:Number = 0; i < ballNum; i++)
{
ball = new Ball(Math.random() * 30);
ball.x = Math.random() * stage.stageWidth;
ball.y = Math.random() * stage.stageHeight;
addChild(ball);
balls.push(ball);
}
addEventListener(Event.ENTER_FRAME, onEnterFrame);
}
protected function onEnterFrame(event:Event):void
{
for(var i:int = 0; i < balls.length; i++)
{
balls[i].x += ax;
}
}
}
}

Answer 1

Give each ball object a different direction and use that to move the ball instead of the ax value.
package
{
import flash.display.Sprite;
import flash.events.Event;
import flash.events.KeyboardEvent;
import flash.text.TextField;
import flash.ui.Keyboard;
public class Dummy extends Sprite
{
private var balls:Array;
private var ball:Ball;
private var ballNum: Number = 10;
private var directions:Array = [new Point(-1,-1),new Point(0,-1),new Point(1,-1),
new Point(-1,0),new Point(1,0),
new Point(-1,1),new Point(0,1),new Point(1,1)];
public function Dummy()
{
init();
}
private function init():void
{
balls = new Array();
for(var i:Number = 0; i < ballNum; i++)
{
ball = new Ball(Math.random() * 30);
ball.x = Math.random() * stage.stageWidth;
ball.y = Math.random() * stage.stageHeight;
ball.direction = directions[Math.floor(Math.random()*directions.length)];
addChild(ball);
balls.push(ball);
}
addEventListener(Event.ENTER_FRAME, onEnterFrame);
}
protected function onEnterFrame(event:Event):void
{
for(var i:int = 0; i < balls.length; i++)
{
balls[i].x += balls[i].direction.x;
balls[i].y += balls[i].direction.y;
}
}
}
}

Answer 2

Give your Ball class properties for speed, and a method move() that will adjust their respective coordinates, and probably will be enhanced to check for collisions sometimes later, so that your balls could rebound of walls for example.
// Ball class additions follow
private var vx:Number;
private var vy:Number;
public function Ball() {
// ... original constructor here
var angle:Number=Math.random(2.0*Math.PI); // random angle
var vel:Number= MAX_VELOCITY*(0.5+0.5*Math.random()); // random velocity module
// define this constant^
vx=vel*Math.cos(angle);
vy=vel*Math.sin(angle); // composites of velocity
}
public function move():void {
this.x+=vx;
this.y+=vy;
}
// main class
protected function onEnterFrame(event:Event):void
{
for(var i:int = 0; i < balls.length; i++)
{
balls[i].move();
}
}