actionscript 3 - AS3: Fast hovering doesn't execute rollOut -

i'm having serious problem getting me nervous:

i've made button _btn includes rollover , rollout animations coding (an nested movieclip instance called barra increases half alpha when hover on , decreases when hover out).

[here should go descriptive image i'm new , need 10 reputation. i'll appreciate help]

this works the problem occurs when move cursor 1 point another, button in between. seems rollout function not detected, rollover animation keeps working (and if carefully, animation stops few seconds , continues).

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this code in actions layer:

//funciones roll on function _btnover(event:mouseevent):void {     _btn.buttonmode = true;     _btn.addeventlistener(event.enter_frame,_btnfadein); }  function _btnfadein(event:event):void {     _btn.barra.alpha += 0.1;     if (_btn.barra.alpha >= 0.5)     {     _btn.removeeventlistener(event.enter_frame,_btnfadein);     } }  _btn.addeventlistener(mouseevent.roll_over,_btnover);   //funciones roll out function _btnout(event:mouseevent):void { _btn.addeventlistener(event.enter_frame,_btnfadeout); }  function _btnfadeout(event:event):void {     _btn.barra.alpha -= 0.1;     if (_btn.barra.alpha <= 0.2)     {     _btn.removeeventlistener(event.enter_frame,_btnfadeout);     } }  _btn.addeventlistener(mouseevent.roll_out,_btnout); 

click here if want download fla , swf files, can see problem clearly.

i barely know how use actionscript 3 (my programming knowledge processing) , don't have time learn head toe, i've researched problem , it's still not clear.

with tutorials , guides, managed learn how create , understand code, , i think problem might in functions of events roll_over , roll_out, contain addeventlistener of enter_frame events (where animations are), respectively. don't know have fix it, should add or change.

i glad if this, i'm frustrated! recommend me do?

thanks in advance

(pd: don't understand of programming language. if can clear , direct possible, i'll appreciate it)

i edited code in here, checking hover state onloop function, can change settings on here

import flash.events.event;  var isrolledover:boolean = false;  //funciones roll on function _btnover(event:mouseevent):void {     isrolledover = true; }  function _btnout(event:mouseevent):void {     isrolledover = false; }  _btn.addeventlistener(mouseevent.roll_over,_btnover);  _btn.addeventlistener(mouseevent.roll_out,_btnout);  this.addeventlistener(event.enter_frame,onloop);  function onloop(e){     if(this.isrolledover){         if(_btn.barra.alpha < 0.5) _btn.barra.alpha += 0.1;     }     else{         if(_btn.barra.alpha > 0.5 || _btn.barra.alpha > 0) _btn.barra.alpha -= 0.1;     } } 

i added sample fla in case