[as3] enterFrame イベントの管理

import com.seyself.events.EnterFrame;
import com.seyself.events.EnterFrameEvent;
import flash.display.Sprite;

function emptiedHandler( event:EnterFrameEvent )
{
  trace("empty");
}
EnterFrame.addEventListener( "emptied" , emptiedHandler );

function registeredHandler( event:EnterFrameEvent )
{
  trace("registered / "+event.currentTarget);
}
EnterFrame.addEventListener( "registered" , registeredHandler );

function  removedHandler( event:EnterFrameEvent )
{
  trace("removed / "+event.currentTarget);
}
EnterFrame.addEventListener( "removed" , removedHandler );

for(var i=0;i<10;i++){
  creater(i);
}

function creater( i )
{
  var sprite:Sprite = new Sprite();
  sprite.graphics.beginFill( 0x666666 , 1 );
  sprite.graphics.drawRect( 0, 0, 20 , 20 );
  sprite.y = i*10;
  sprite.x = i*4;
  var tx = Math.random()*800;
  var ty = Math.random()*800;
  function enterFrameHandler( event:EnterFrameEvent )
  {
    sprite.x += (tx-sprite.x)/3;
    sprite.y += (ty-sprite.y)/3;
    if( event.currentTime==20 ){
      event.remove();
    }
  }
  EnterFrame.register( enterFrameHandler , sprite , i*3 );
  this.addChild( sprite );
}