package {
    import flash.display.Sprite;
	import flash.events.Event;
	import flash.events.MouseEvent;
	import flash.utils.Timer;
	import flash.events.TimerEvent;
	import flash.geom.Point;
	
    public class Circle extends Sprite {
		private const RADIUS:Number = 150;
		
		private var _floorObj:Sprite;
		private var _obj/*Sprite*/:Array;
		private var _clickedNum:int = -1;
		private var _angle:Number = 0;
		private var _timer:Timer;
		
        public function Circle() {
            // write as3 code here..
            _obj = [];
			
			for (var i:int = 0; i < 12; i++) {
				var sp:Sprite = new Sprite();
				sp.graphics.beginFill(Math.random() * 0xFFFFFF);
				sp.graphics.drawCircle(0, 0, 30);
				sp.graphics.endFill();
				_obj.push(sp);
				var num:Number = _obj.length -1;
				this.addChild(_obj[num]);
				_obj[num].buttonMode = true;
				
				_obj[num].name = String(num);
				_obj[num].x = this.stage.stageWidth / 2;
				_obj[num].y = this.stage.stageHeight / 2;
				_obj[num].scaleX = _obj[num].scaleY = 0;
				_obj[num].addEventListener(MouseEvent.CLICK, _onClick);
			}
			
			_floorObj = new Sprite();
			_floorObj.graphics.beginFill(0xFF0000);
			_floorObj.graphics.drawRect(0, 0, this.stage.stageWidth, this.stage.stageHeight);
			_floorObj.graphics.endFill();
			_floorObj.alpha = 0;
			_floorObj.addEventListener(MouseEvent.CLICK, _onFloorClick);
			this.addChildAt(_floorObj, 0);
			
			_timer = new Timer(33);
			_timer.addEventListener(TimerEvent.TIMER, _loop);
			_timer.start();
        }
		
		private function _onClick(e:MouseEvent):void {
			if (_clickedNum == int(e.target.name)) {
				_clickedNum = -1;
			}
			else {
				_clickedNum = int(e.target.name);
			}
		}
		
		private function _onFloorClick(e:MouseEvent):void {
			_clickedNum = -1;
		}
		
		private function _loop(e:TimerEvent):void {
			_angle += .002;
			for (var i:int = 0; i < _obj.length; i++) {
				var pos:Point = new Point();
				var scale:Number;
				
				if (_clickedNum == i) {
					pos.x = this.stage.stageWidth / 2;
					pos.y = this.stage.stageHeight / 2;
					scale = 1;
				}
				else {
					pos.x = this.stage.stageWidth / 2 + RADIUS * Math.cos(_angle + i / _obj.length * Math.PI * 2);
					pos.y = this.stage.stageHeight / 2 + RADIUS * Math.sin(_angle + i / _obj.length * Math.PI * 2);
					scale = .3;
				}
				_obj[i].x += (pos.x - _obj[i].x) / 5;
				_obj[i].y += (pos.y - _obj[i].y) / 5;
				_obj[i].scaleX += (scale - _obj[i].scaleX) / 5;
				_obj[i].scaleY += (scale - _obj[i].scaleY) / 5;
			}
		}
    }
}

Sprites on a Circle