android RecyclerView 심플 구현. kotlin

텍스트뷰만 있는 간단한 RecyclerView 구현이다.

activity layout xml 파일에 RecyclerView 을 추가한다.

<androidx.recyclerview.widget.RecyclerView
    android:id="@+id/text_list"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
    />

listitem_contents.xml 파일을 layout 폴더에 추가한다.

<?xml version="1.0" encoding="utf-8"?>

<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/item_text"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:gravity="center_vertical"
    android:paddingStart="?android:attr/listPreferredItemPaddingStart"
    android:paddingEnd="?android:attr/listPreferredItemPaddingEnd" />

Adapter 클래스를 추가한다.

class ContentsAdapter(private val textList: MutableList<String>) :
    RecyclerView.Adapter<ContentsAdapter.ContentsHolder>() {

    class ContentsHolder(val textView: TextView) : RecyclerView.ViewHolder(textView)


    interface ItemClick
    {
        fun onClick(view: View, position: Int)
    }
    var itemClick: ItemClick? = null

    override fun onCreateViewHolder(parent: ViewGroup,
                                    viewType: Int): ContentsAdapter.ContentsHolder {
        val textView = LayoutInflater.from(parent.context)
            .inflate(R.layout.listitem_contents, parent, false) as TextView
        return ContentsHolder(textView)
    }

    override fun onBindViewHolder(holder: ContentsHolder, position: Int) {
        holder.textView.text = textList[position] ?: ""

        if(itemClick != null)
        {
            holder?.textView?.setOnClickListener { v ->
                itemClick?.onClick(v, position)
            }
        }
    }

    override fun getItemCount() = textList.size
}

Activity onCreate 코드에서 다음과 같이 추가한다.

itemClick은 클릭했을때의 리스너다. 클릭 처리가 없다면 삭제한다.

var list = mutableListOf<String>()
var viewAdapter: RecyclerView.Adapter<*> = ContentsAdapter(list)
(viewAdapter as ContentsAdapter).itemClick = object: ContentsAdapter.ItemClick {
    override fun onClick(view: View, position: Int) {
        try {

            <You Code>

        } catch (e: Exception) {

        }
    }
}
val recyclerView : RecyclerView = findViewById(R.id.body_text_list)
recyclerView.adapter = viewAdapter