I want a TextArea that will act like a TextInput that increases its width if user types text longer than TextArea width.

---------------------------- DynamicWidthTextArea.as ------------------------------

package {
  import flash.events.Event;
 
  import mx.controls.TextArea;
 
  public class DynamicWidthTextArea extends TextArea{
    public function DynamicWidthTextArea(){
      super();
      super.horizontalScrollPolicy = "off";
      super.verticalScrollPolicy = "off";
      super.wordWrap = false;
      this.addEventListener(Event.CHANGE, adjustWidthHandler);
    }
   
    private function adjustWidthHandler(event:Event):void{
      if(width <= textField.textWidth +
textField.getLineMetrics(0).width){
        width = textField.textWidth;     
        validateNow();
      }
    }
   
    override public function set text(val:String):void{
      textField.text = val;
      validateNow();
      width = textField.textWidth;
      validateNow();
    }
   
    override public function set htmlText(val:String):void{
      textField.htmlText = val;
      validateNow();
      width = textField.textWidth;
      validateNow();
    }
    override public function set width(value:Number):void{
      if(textField == null){
        if(width <= value){
          super.width = value;
        }
      }else{       
        trace("width: " + width);
        trace("super.maxWidth: " + super.maxWidth);
        if (textField.getLineMetrics(0).width<= super.maxWidth){
          trace("textField.textWidth: " + textField.textWidth);
          trace("textField.getLineMetrics(0).width: " +
textField.getLineMetrics(0).width);
          if(width <= textField.getLineMetrics(0).width + 10){
            super.width = textField.getLineMetrics(0).width + 10;
          }        
        }else{
            super.width = super.maxWidth;         
        }  
      }
    }
   
    override public function get text():String{
        return textField.text;
    }
   
    override public function get htmlText():String{
        return textField.htmlText;
    }
  
    override public function set maxWidth(value:Number):void{
      super.maxWidth = value;
    }
  }
}

---------------------------------- Test.mxml ---------------------------------

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx=" http://www.adobe.com/2006/mxml"
  xmlns:comp="*">
  <mx:HBox>
    <mx:Label text="Font size 8: "/>
    <comp:DynamicWidthTextArea width="100" fontSize="8"/>   
  </mx:HBox>
  <mx:HBox>
    <mx:Label text="Font size 10: "/>
    <comp:DynamicWidthTextArea width="100" fontSize="10"/>   
  </mx:HBox>
  <mx:HBox>
    <mx:Label text="Font size 12: "/>
    <comp:DynamicWidthTextArea width="100" fontSize="12"/>   
  </mx:HBox>
  <mx:HBox>
    <mx:Label text="Font size 20: "/>
    <comp:DynamicWidthTextArea width="100" fontSize="20"/>   
  </mx:HBox>
  <mx:HBox>
    <mx:Label text="Font size 40: "/>
    <comp:DynamicWidthTextArea width="100" height="100"
fontSize="40"/>   
  </mx:HBox>
  <mx:HBox>
    <mx:Label text="Font size 100: "/>
    <comp:DynamicWidthTextArea width="200" height="120"
fontSize="100"/>   
  </mx:HBox>
</mx:Application>