[bicubic_bublic]

public class Controller {
 
	private var obj:Object;
	private var textField:TextField;
	private var propName:String;
 
	public function Controller(textField:TextField, obj:Object, propName:String) {
		this.textField = textField;
		this.obj = obj;
		this.propName = propName;
 
		update(true);
		textField.addEventListener(Event.CHANGE, onTFChange);
	}
 
	private function onTFChange(e:Event) {
		update();
	}
 
	public function update(back:Boolean = false) {
		if (back) {
			textField.text = obj[propName];
		} else {
			obj[propName] = textField.text;
		}
	}
 
}

для массива:

new Controller(tf1, arr, 2);

для объекта:

new Controller(tf1, obj, 'prop');