CurrencyRow.kt

class CurrencyRow(context: Context?, attrs: AttributeSet? = null) :
    ConstraintLayout(context, attrs) {

    val scrollableArea: ConstraintLayout
    ...

    init {
        LayoutInflater.from(context).inflate(R.layout.row_currency, this)
        scrollableArea = findViewById(R.id.scrollable_area)
        ...
    }
    ...
}