Recycler View in Kotlin

By

Vineel Sai

profile

To create a recycler view in kotlin you need three classes, an Adapter class to set data to items in the recycler view a data class to give your data a structure, and an activity or fragment class to display the view.

Add dependencies

  • Add the following dependencies to your build.gradle file
implementation 'androidx.recyclerview:recyclerview:1.1.0' implementation 'androidx.cardview:cardview:1.0.0'

Write Code

  • Create a data class, you can pass the variables you want to access later as parameters in the data class
data class Item(val text: String)
  • Create an adapter class
class Adapter(private val List: List<Item>) : RecyclerView.Adapter<Adapter.ViewHolder>() { class ViewHolder(view: View) : RecyclerView.ViewHolder(view) { val text: TextView = view.findViewById(R.id.text) init { // You can add onClick Listeners here } } override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder { val item = LayoutInflater.from(parent.context).inflate(R.layout.item, parent, false) return ViewHolder(item) } override fun onBindViewHolder(holder: ViewHolder, position: Int) { val element = List[position] holder.text.text = element.text } override fun getItemCount(): Int { return List.size } }
  • Create an Activity where you want to display here I am feeding the view with dummy data you can add whatever data you want
class MainActivity : AppCompatActivity() { override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) view.adapter = Adapter(generateDummyList(1000)) view.layoutManager = LinearLayoutManager(this) view.hasFixedSize() } private fun generateDummyList(size: Int): List<Item> { val list = ArrayList<Item>() for (i in 0 until size) { val item = Item("Item $i") list += item } return list } }

The entire code used is in the GitHub repohttps://github.com/vineelsai26/Recycler-View-Kotlin

Happy Coding!!!