CustomView.kt

class SegmentView(context: Context, attrs: AttributeSet) : LinearLayout(context, attrs) {

    init {
        View.inflate(context, R.layout. segment_button, this);
        val btnSeg1: Button = findViewById(R.id.button)
        val btnSeg2: Button = findViewById(R.id.button2)

    }
}

Mainactivity.kt

fun toastMe(v: View) {
        val myToast = Toast.makeText(this, "Toast me clicked", Toast.LENGTH_LONG)
        myToast.show()
    }

    fun countMe(v: View) {
        val shouldCountTextMe = findViewById<TextView>(R.id.textView)
        val countStr = shouldCountTextMe.text.toString()

        var count: Int = Integer.parseInt(countStr)

        count++
        shouldCountTextMe.text = count.toString();

    }

    fun countYou(id: Int){
        when(id) {
            1 -> {
                Log.d("Loi", "FONT");
            }
            2 -> {

            }
        }
    }