Visibility Not working with Kotlin

use play.visibility=View.VISIBLE to visible and play.visibility=View.GONE to invisible or to hide

You have a mistake in your code, visibility constant should be set from Class variable, not from argument variable. Change view.INVISIBLE by View.INVISIBLE

fun onPlay(view: View){
     var play = findViewById(R.id.play) as Button
     play.isClickable=false
     play.visibility= View.INVISIBLE // v letter should be capital
}