GroupBallListAdapter.kt

var values: List<GroupDetail> = listOf()
	set(items) {
		field = items
		notifyDataSetChanged()
	}

override fun onBindViewHolder(holder: ViewHolder, position: Int) {
	with(holder) {
		value.keys.filterIndexed { index, _ -> index == position }
			.firstOrNull()?.let { key ->
				textViewGroupName.text = "GROUP ${key.toUpperCase()}"
				val groupList = value[key]
				val groupBallItemAdapter = GroupBallItemAdapter()
				groupBallItemAdapter.values = groupList ?: listOf()
				recyclerViewGroupTeam.adapter = groupBallItemAdapter
			}
	}
}