Kotlin Programming Cookbook

How to do it…

Let's see an example where ISP can help us:

1. This is a simple example of a "fat" interface:

button.setOnClickListener(object : View.OnClickListener {    fun onClick(View v) {       // TODO: do some stuff...           }        fun onLongClick(View v) {        // we don't need it    }    fun onTouch(View v, MotionEvent event) {        // we don't need it    } });

2. As you can see, the problem of a big interface is that we are forced to implement the methods even if we don't have anything to do it in there.
3. A simple solution is to break that interface into smaller interfaces, like the following code:

interface OnClickListener {     fun onClick( v:View )}public interface OnLongClickListener {     fun onLongClick( v: View)}interface OnTouchListener {     fun onTouch( v: View, event: ...