[FMX]Spaces in dynamic text field

1

I made the following function to fade in and out four clips:

function fadeSq (clips, fade, speed){
 while (clips.length){
  clips[0].onEnterFrame = function(){
   var fadeOut = fade - this._alpha;
   this._alpha += fadeOut /speed;
  };
   clips.splice(0, 1);
 }
}

and I’m calling the code this way:

this.fadeSq ([btn_about_us, btn_Products, btn_product_codes, btn_contact_us], 0, 3);

As you al can see am I using underscores in the call back function, which I don’t want because I want to display the information in a dynamic textfield. But when I leave open spaces I get all kind of errors. How can I prevend this?