List 表示

RecyclerView と ViewBinding

この設定をしておくと findViewById() が不要になる・・？

kts

android {
	...
	buildFeatures {
	    viewBinding = true
	}
}

kt

class MainFragment : Fragment() {
	...
	private lateinit var binding: MainFragmentBinding

	// Chap 9 で詳しくやるそう
	override fun onCreateView(
	    // return inflater.inflate(R.layout.main_fragment, container, false)
		// ↑
		// これはデフォルトの実装

		inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View {

		// id: lists_recyclerview に対応
		binding.listsRecyclerview.layoutManager = LinearLayoutManager(requireContext())
		binding.listsRecyclerview.adapter = ListSelectionRecyclerViewAdapter()

	    binding = MainFragmentBinding.inflate(inflater, container, false)
	    return binding.root
	}

新規

kt

class ListSelectionViewHolder(val binding: ListSelectionViewHolderBinding)
	: RecyclerView.ViewHolder(binding.root) {

	// これは layout/Resource に作成した list_selection_view_holder に対応
}

class ListSelectionRecyclerViewAdapter
	: RecyclerView.Adapter<ListSelectionViewHolder>() {

	override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ListSelectionViewHolder {
		val binding = ListSelectionViewHolderBinding.inflate(LayoutInflater.from(parent.context), parent, false)
		return ListSelectionViewHolder(binding)
	}
	override fun getItemCount(): Int {
	    return listTitles.size
	}
	override fun onBindViewHolder(holder: ListSelectionViewHolder, position: Int) {
	    ...
	}
}