以下是一个使用Kotlin和RecyclerView实现搜索功能的示例代码：

1. 创建数据类：

data class Item(val id: Int, val name: String)

2. 创建RecyclerView的适配器：

class ItemAdapter(private val items: List) : RecyclerView.Adapter() {
    private var filteredItems: List = items

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

    override fun onBindViewHolder(holder: ItemViewHolder, position: Int) {
        val item = filteredItems[position]
        holder.bind(item)
    }

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

    fun filter(query: String) {
        filteredItems = if (query.isEmpty()) {
            items
        } else {
            items.filter { it.name.contains(query, true) }
        }
        notifyDataSetChanged()
    }

    inner class ItemViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        fun bind(item: Item) {
            itemView.textView.text = item.name
        }
    }
}

3. 在Activity或Fragment中使用RecyclerView和EditText：

class MainActivity : AppCompatActivity() {
    private lateinit var recyclerView: RecyclerView
    private lateinit var editText: EditText
    private lateinit var itemAdapter: ItemAdapter

    private val items = listOf(
        Item(1, "Apple"),
        Item(2, "Banana"),
        Item(3, "Cherry"),
        Item(4, "Grape"),
        Item(5, "Lemon"),
        Item(6, "Orange")
    )

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        recyclerView = findViewById(R.id.recyclerView)
        editText = findViewById(R.id.editText)

        itemAdapter = ItemAdapter(items)
        recyclerView.adapter = itemAdapter
        recyclerView.layoutManager = LinearLayoutManager(this)

        editText.addTextChangedListener(object : TextWatcher {
            override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {}

            override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
                itemAdapter.filter(s.toString())
            }

            override fun afterTextChanged(s: Editable?) {}
        })
    }
}

请确保在布局文件中包含一个名为"recyclerView"的RecyclerView和一个名为"editText"的EditText。

这段代码将根据用户在EditText中输入的文本来过滤RecyclerView中的数据项，并通过调用filter()方法在适配器中实现搜索功能。搜索结果将实时显示在RecyclerView中。