text-shuffle 練習です。

/**
 * Copyright plus-tic ( http://wonderfl.net/user/plus-tic )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/eDq7
 */

/*text-shuffle 一度やってみたかったので
http://hato-style.chu.jp/note/rnd_text.html参考に
作成させていただきました。少しづつ解読したいです。*/

package{
 import flash.display.MovieClip;
 import flash.text.TextField;

 public class index extends MovieClip {
  private var tf:TextField;
  private var tf1:TextField;
  
  public function index():void {
   var rt:randomText;

   tf = new TextField();
   tf.x = 50;
   tf.y = 50;
   tf.text = 'text-shuffle';
   addChild(tf);
   
   tf1 = new TextField();
   tf1.x = 150;
   tf1.y = 50;
   tf1.text = "shigenokai";
   addChild(tf1);
   

   rt = new randomText(tf);//ここに対応するTextFieldを引数として渡す
   rt.start();
   
   rt = new randomText(tf1);
   rt.start();  
   }
 }
}

 import flash.display.DisplayObjectContainer;
 import flash.text.TextField;
 import flash.events.Event;
 import flash.events.TimerEvent;
 import flash.utils.Timer;

 class randomText{
  private var defaultTxt:String;
  private var searchTxt:String = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789!?#$%&/+-=;_:'
  private var tt:TextField;
  private var compTxt:String = '';
  private var nowLen:uint = 0;
  private var Interval:uint = 10;
  private var Change:uint = 10;
  private var time:Timer;

  public function randomText(t:TextField):void{
   defaultTxt = t.text;
   tt = t;
   tt.text = '';
  }

  public function start():void{
   time = new Timer(Interval,Change);
   time.addEventListener(TimerEvent.TIMER,randomText_search);
   time.addEventListener(TimerEvent.TIMER_COMPLETE,randomTextComp);
   time.start();
  }

  public function stop():void{
   time.stop();
   time.removeEventListener(TimerEvent.TIMER,randomText_search);
   time.removeEventListener(TimerEvent.TIMER_COMPLETE,randomTextComp);
  }

  private function randomText_search(e:Event):void{
   tt.text = compTxt + searchTxt.charAt(Math.floor(Math.random()*searchTxt.length));
  }

  private function randomTextComp(e:Event):void{
   compTxt = compTxt + defaultTxt.charAt(nowLen);
   tt.text = compTxt;

   if(nowLen <= defaultTxt.length - 2 ){
    ++nowLen;
    start();
   }else{
    stop();
   }
  }
 }