TweenQueue.as

package pierlis.framework
{
  import flash.events.*
  import fl.transitions.*
  import pierlis.framework.*
  
  /*
  var tq = new TweenQueue()
  tq.push(function(){ new Tween(...) })
  tq.push(function(){ new Tween(...) })
  
  tw.addEventListener(TweenEvent.MOTION_FINISH, myCallback)
  */
  
  public class TweenQueue extends EventDispatcher
  { 
    public var push:Function

    public function TweenQueue(eventType = null) 
    {
      this.eventType = (eventType || TweenEvent.MOTION_FINISH)
      push = firstPush
    }
    
    private var eventType
    private var currentTween
    private var queuedFun
    
    private function firstPush(fun)
    {
      currentTween = fun(this)
      currentTween.addEventListener(eventType, onQueueFinish)
      push = secondPush
    }
    
    private function secondPush(fun) 
    {
      queuedFun = fun
      currentTween.removeEventListener(eventType, onQueueFinish)
      currentTween.addEventListener(eventType, onIntermediateFinish)
      push = thirdPush
    }
    
    private function thirdPush(fun)
    {
      queuedFun = fun
    }
    
    private function onQueueFinish(e)
    {
      push = firstPush
      dispatchEvent(e)
    }
    
    private function onIntermediateFinish(e)
    {
      currentTween = queuedFun()
      currentTween.addEventListener(eventType, onQueueFinish)
      push = secondPush
    }
  }
}