private var _tween:Tween;

...

_tween = new Tween( ... );

 

private const _tweens:Dictionary = new Dictionary();

 

// или в массиве

//private const _tweens:Array = new Array();

 

private function nextTween():void {

    const tween:Tween = new Tween();

    this._tweens[tween] = true;

    //this._tweens.push(tween);

    tween.addEventListener(TweenEvent.MOTION_FINISH, this.handler_tweenComplete, false, int.MAX_VALUE);

    tween.start();

}

 

private function handler_tweenComplete(event:Event):void {

    const tween:Tween = event.target as Tween;

    delete this._tweens[tween];

    //this._tweens.splice(this._tweens.indexOf(tween), 1);

}