activity kotlin RecyclerView 左滑删除item 全部代码实现 详细

以下是 Kotlin 实现 RecyclerView 左滑删除 item 的完整代码：

1. 在布局文件中添加 RecyclerView：

<androidx.recyclerview.widget.RecyclerView
    android:id="@+id/recyclerView"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

2. 创建 RecyclerView 的 Adapter 类：

class MyAdapter(private val itemList: MutableList<String>) :
    RecyclerView.Adapter<MyAdapter.MyViewHolder>() {

    class MyViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        val itemText: TextView = itemView.findViewById(R.id.itemText)
        val deleteBtn: ImageButton = itemView.findViewById(R.id.deleteBtn)
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
        val itemView = LayoutInflater.from(parent.context)
            .inflate(R.layout.item_layout, parent, false)
        return MyViewHolder(itemView)
    }

    override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
        holder.itemText.text = itemList[position]
        holder.deleteBtn.setOnClickListener {
            itemList.removeAt(position)
            notifyItemRemoved(position)
        }
    }

    override fun getItemCount(): Int {
        return itemList.size
    }
}

3. 在 Activity 或 Fragment 中初始化 RecyclerView：

val recyclerView: RecyclerView = findViewById(R.id.recyclerView)
val itemList = mutableListOf<String>("Item 1", "Item 2", "Item 3", "Item 4", "Item 5")
val adapter = MyAdapter(itemList)
recyclerView.adapter = adapter
val itemTouchHelper = ItemTouchHelper(itemTouchHelperCallback)
itemTouchHelper.attachToRecyclerView(recyclerView)

4. 创建 ItemTouchHelper.Callback 类，并实现左滑删除的逻辑：

val itemTouchHelperCallback = object : ItemTouchHelper.Callback() {

    override fun getMovementFlags(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder): Int {
        val dragFlags = 0
        val swipeFlags = ItemTouchHelper.LEFT or ItemTouchHelper.RIGHT
        return makeMovementFlags(dragFlags, swipeFlags)
    }

    override fun onMove(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder, target: RecyclerView.ViewHolder): Boolean {
        return false
    }

    override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
        val position = viewHolder.adapterPosition
        itemList.removeAt(position)
        adapter.notifyDataSetChanged()
    }
}

5. 最后，记得在 RecyclerView 的 item 布局文件中添加左滑删除按钮：

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <TextView
        android:id="@+id/itemText"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:padding="16dp"
        android:textSize="18sp" />

    <ImageButton
        android:id="@+id/deleteBtn"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:background="@null"
        android:padding="16dp"
        android:src="@drawable/ic_delete" />

</LinearLayout>

以上就是 RecyclerView 左滑删除 item 的完整代码实现。