text_listener.kt

 editText.addTextChangedListener(object: TextWatcher {

            override fun afterTextChanged(s: Editable?) {
                textAge.text = s.toString()
            }

            override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {

            }

            override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
                println(s)
                textAge.append(s)
            }


        })